For all you watercooling nuts out there - hard data

[r0ckstarbob]

i've been tabulating data on polar coolants used in computer water cooling setups for the past 3 weeks and these are my results.

My focus for this research was to find a coolant that would work at -30F for my project aka The Core Project. for those of you considering going a sub-Z route, or just want to put your coolant below freezing (32F), this is something you'll probably be interested in.

as for using antifreeze in your system, well, the numbers speak for themselves.

big props go out to Karsta (here on the forums) and myv65 (Dave Smith on the AMDmB forums- the author of that cooling article that Hoot has stickied at the top). both of whom i've been corresponding with and have been absolutely fantastic in providing me with answers and overall knowlege when i just plain ol got stuck somewhere, trying to understand all this. these are some REALLY knowlegeable and helpful guys, and not only in regards to coolants. they've been absolutely great. i can't express enough gratitude. big props also go out to Tenax too (also on the AMDmB forums). All three of them have been of invaluable aid. Thanks guys.

i can explain anything that you might have questions on here. and if i can't, i know a couple of guys that can. ;)




:::::::::::::::::::::::::::::: EDIT ::::::::::::::::::::::::::::::::::




it's been a long time since i initially posted this. much has changed and i've lost some of the original data due to HDD corruption and so forth. consequently, the original chart doesn't exist any longer. what DOES still exist are the graphs i created from the data in that chart, and those you can find by scrolling down the page here. sorry for the hassle and gunk, and i'm sorry the original chart doesn't exist any longer. if you want a quick and easy answer to what is the best stuff to use for a coolant, it's this...

#1 me love you long time GI....
Methanol/Distilled Water (33:66 ratio) aka windshield wiper fluid

although it's actual thermal properties aren't quite as good as straight up water, it's viscosity rocks the casbah and so what you're you loose in quality you make up for in quantity at about a 15% increase in performance over water... even at (or above) ambient room temp. sound great? well, truth is in all honesty you'll probably be hard pressed to see 15% performance increase in a real world scenario, but it should be there. this ratio will also give you an operational range of approximately 90C to -23C... or well below freezing. should use this stuff in a closed system though. or at least no bongs. this ratio of methanol to water isn't particularly lethal, but don't drink the stuff for gods sake. the other name for Methanol is wood alcohol. if you're operating above freezing temps at around ambient, go with 100% distilled water on general principle. it's just going to be better.


#2 100% Distilled water

best stuff around, damn hard to beat. no kidding. usually it's even better than the above stuff.


#3 Ethanol/Water (aka vodka) ratio varies

if you're going below zero and have moral issues with windshield wiper fluid and you just HAVE to get below zero, use Ethanol and water. Ethanol is Grain alcohol, and what they make booze out of. you want to use as little of this stuff in your water as possible so go sparingly. the more of this stuff you use, the less efficient your coolant is going to be because it's Ethanols thermal properties aren't as good as waters, and it's also thicker than water so the more of this stuff you use, the thicker your coolants going to get. don't tell your roomie you're cooling your stuff with Vodka or risk comming home to your boy on the floor with a hose in his pie hole being shotgunned by your Antec.

*** shudder ***


#4 Isopropyl/Water (aka 2-propanol aka rubbing alcohol)

ghetto fabulous baby, same cautions apply as above, this stuffs even worse than ethanol but it will work. the good points of it are your roomie won't touch it.


#5 Antifreeze/Water (50:50 ratio)

last and least good for your system... if you're hard up, don't have a leg to cut off for something better, on a desert island and only have this crap, well go for it. a 50:50 ratio will quarantee you down to -10 but the results are so disgusting compared to what you could get if you used any of the above items. i've included it here just because so many people consider this a viable option and actually do it. whats sad is they could have such better performance if they used the alcohols instead. ah well. C'est La Vie.



:::::::::::::::::::::::::::: end of edit ::::::::::::::::::::::::::



please scroll down for the graphs and charts.

i hope this is helpful. enjoy your read.

RSB

[Coolio]

WHOA now that's comprehensive!:D
And interesting:D
and informative;)

[train22]

very imporessive, keep us informed with real pics!

[r0ckstarbob]

thank you.

real pics are a ways off still. have been in the design stage of The Core Project for about 4 months now. next week i cut the final design plans/specs. it'll probably be another 6 to 9 months before it actually gets built. when we start up on it, i'll definately post some pics.

[Gravity Man]

Excellent information, but I was wondering if anyone had any info on Water Wetter?

[VashTheStampede]

You got a hold of that 40 Below Pro-Blend stuff yet rockstar?

~RT~

[r0ckstarbob]

about ProBlends 40-Below antifreeze additive

not yet. the guy was quick to pat me on the head and offer me a discount without giving me any data. while it was a nice gesture, 5 dollars off the product doesn't come close to the value of the data, or the price of a new system if it affects it adversely and blows my stuff up ya know? (not that i really think it will do that but you see my point...)

regardless, i sent another email today. hopefully will hear something back by monday, though last time he responded the next day.

as far as water wetter is concerned, most of the information i've gotten has been from their tech sheets they have on line which seem to be pretty comprehensive.

one small fact i should point out that i noticed. they made the statement that using 50% antifreeze and water reduced the heat transfer ability of water by HALF. thats not correct. it only reduces the heat transfer capacity of water by 30%, though it IS half the difference between waters efficiency and the efficiency of antifreeze. just something i noticed. now that i know what i'm looking at when i look at these numbers, actually glycol wouldn't be so bad to use if the viscocity didn't absolutely and unequivicably SUCK more then almost anything else short of peanutbutter.

anyhow, heres some good tech info on water wetter.
http://www.redlineoil.com/redlineoil/wwti.htm

the minute i get ahold of anything on ProBlends 40-Below i'll definately post something about it. maybe it's just me being a little sensitive about it but i didn't particularly like how he totally skated around me and my inquiries. we'll see if theres anything else to come back from them. failing that, we may have to resort to more stringent measures :cool:

[The Overclocker]

wow, that is amazing, i just hope you have a good cpu, or all this effort wil be for nothing

[r0ckstarbob]

thanks!!! :) man i've been working my butt off for a little over a month straight now just trying to compile all this accurately and cleanly


as for CPU and so forth... yup. i'm good to go.

[Arkamedies]

I wonder if we could get this made into a sticky for a month or so... it is excellent info!

:cool:

[Karsta]

Thanks for kind words r0ckstarbob. You've done excellent job. I hope that that chart will be up as a sticky or in articles. (tiny note: you still have that isopropyl there - it should be 2-propanol or isopropyl alcohol)

[r0ckstarbob]

you're more then welcome. thank you for the help. will PM Hoot as to the possibility of making it a sticky or something - or might even write a small article about it basically explaining it all.

[JigPu]

Great data man!! If it wern't for the bump I might have never seen it!! One question. What does specific heat have to do with thermal transfer properties? I have had to mess with thermal conductivity before (last year in physics), but I don't remeber ever having to mess with the specific heat of substances. That was all chemestry....

JigPu

[r0ckstarbob]

well from what i've been able to gather it's this.

Specific Heat (aka Heat Capacity, Thermal Capacity) is really only relavant when held in direct comparison with the Thermal Conductivity. there is a relationship between how much thermal energy a substance can hold/store (per gram) and how much it conducts/absorbs. things like liquids (water for example) can absorb/hold more thermal energy per gram then metal (ie copper), but it conducts it (sheds it) much more poorly then copper.

the relationship between the Thermal Capacity and the Thermal Conductivity is called the Thermal Differential. the higher the Thermal Differential, the better.

in theory, the ways of improving the Thermal Differential would be to either find a way to increase the Conductivity or reduce the Capacity. using the latter method however puts more strain on your radiator and requires better flow rates as your liquid will become more sensitive to thermal changes, in either direction.

[r0ckstarbob]

graphed data comparisons


Freezing Point: (lower the better)
http://speakeasy.net/~language/images/graph-freezingpoint.gif



Thermal Capacity: The Thermal Capacity -aka specific heat- figures are used only in reference to the Thermal Conductivity and is used to find the Thermal Differential.
The Thermal Capacity is how much Thermal Energy these substances can absorb/store.
http://speakeasy.net/~language/images/graph-capacity.gif



Thermal Conductivity: The Thermal Conductivity rates how quickly these substances can absorb and transmit thermal energy and generally has the most direct bearing on cooling for our purposes.
(The higher the better)
http://speakeasy.net/~language/images/graph-conductivity.gif



Thermal Differential: The Thermal Differential is the overall rating of the substance based upon the Thermal Capacity and the Thermal Conductivity of a substance. When it's all said and done, this is the chart/number that has to be looked at when putting the whole schebang together. This is the sum of a substances total effectiveness as a cooling medium (minus viscosity that is)
(the higher the better)
http://speakeasy.net/~language/images/graph-differentialliquid.gif
(higher the better)
http://speakeasy.net/~language/images/graph-differentialmetal.gif



This is the Kinematic Viscosity ratings of these liquids. It is measured by dropping a sphere into a bucket of liquid and measuring how quickly it reaches the bottom. It effectively measures the amount of drag upon an object passing through it and is measured in Stokes. The industrial standard is measured in Centistokes (cSt).

the lower the number = the thinner the liquid.
the thinner the liquid = the better the viscosity (for our purposes that is)
the lower the viscosity = the faster we are able to pump our coolant.
the faster we are able to pump our coolant = the more efficient our cooling mechanism.

low numbers good. high numbers bad.
http://speakeasy.net/~language/kinematicviscosity.gif

The other way to measure viscosity is called the Dynamic Viscosity. Dynamic Viscosity is the measure of resistance of liquid in a tube or capillary. It's measured by pouring liquid in one end of a tube and measuring how quickly it reaches the other end. It is represented in Poise. The industrial standard uses Centipoise (cP). 1 Centipoise = .01 Poise. But as with the Kinematic Viscosity, the lower the rating the better.

http://speakeasy.net/~language/images/graph-viscosity.gif

the Freezing Point, the Thermal Differential, and the Viscosity are the crutial figures to look at when making your decision.

Just a note here: the term "Glycol" in all these figures is short for Ethylene Glycol Antifreeze - Prestone to be exact - using numbers from their most potent antifreeze that they supplied me upon request via email.

The term "Isopropyl" in all these figures refers to Isopropyl Alcohol (rubbing alcohol aka 2-Propanol).

Keep in mind that water is the best stuff around for heat transfer. The closer we can get our liquid to the efficiency of water, the better. Water is the standard in all these figures and the standard in which we are trying to meet or exceed (when possible) when choosing an effecient coolant.

and as always, my knowlege is far from perfect so if you see something that i missed, please feel free to backchannel me at language@speakeasy.net and we'll get it all fixed up.

[Fink]

Great job.

My only comment would be what about other glycol/water ratios and methanol/water ratios. That would be even more informative giving the user the ability to 'tune' Fp to your needs.

[r0ckstarbob]

i can do that. give me a day or two and i'll work some up.

RSB

[Hachet]

Excellent info r0ckstarbob. Thanks for taking the time to post it. I've got a question about the methanol mixture. When it's mixed w/ H20 33/66, is there any chance of this being flamable? Also are there any special considerations in terms of tubing and other gear? I ask because my father has some methanol kicking around from a hybrid vehicle he built and I happen to be building a H20 setup this week. I'm going to have a full size car radiator sitting outside and this will be piped though the siding of my house and into my room. It's already getting below freezing here at night, so I might as well take advantage of it! I also like this idea because I wont need any fans with that big of a radiator sitting outside (this is also a plus for running a system in a house that's off the grid).

Thanks again.
:D

[r0ckstarbob]

As per request by Fink, direct comparisons between Antifreeze and Methanol at different ratios.

I should note here however that nowhere did i actually find these figures, these are figures that i extrapolated based upon the data i have compiled. it should be relatively accurate, or at least close enough to more or less predict efficiency within 5% of true.

What we're looking at here are two very comparable substances. The differences between them are often times negligible, with Methanol generally acting a little bit better then Antifreeze. Where the differences REALLY become evident is in the Viscosity. The Viscosity of Methanol is what really gives it a HUGE lead over Antifreeze from the word go; and the colder it gets, the more apparent that fact becomes. Antifreeze is most definately a great product for cars which operate at 200+ degrees where viscosity doesn't become much of an issue in that kind of heat - the heat thins it out. Methanol would be terrible in a car because of it's extremely low evaporation point. Alternately it's also why Antifreeze is going to be terrible in your computer. Viscosity becomes a BIG issue in computer cooling, especially the colder you go. With computer cooling, the vapor point doesn't often become much of an issue and we don't have much to worry about there (it doesn't take much to reduce that worry to "nil" with a decent radiator in fact). but that Viscosity, man thats the ticket. Water thins out the Antifreeze. Methanol thins out the Water... and the thinner our coolant, the faster we can pump it. the faster we can pump it, the better heat transfer we can effect. Thats how it works kiddies. The fact that it's so potent and has such a low freezing point means that we don't have to use as much of it either which keeps our water to substance ratio considerabley higher with Methanol as opposed to Antifreeze.

Antifreeze should be called Antiboil. thats where it works best and where the focus was on when they designed this stuff initally.

Antifreeze is good for HOT environments
Methanol is good for COLD environments

try to swap them out and you're going to get some really inefficient performance.

anyhow, here ya go...

Graphed data comparisons between Antifreeze and Methanol at various ratios.

Freezing Point: (Lower the better) IMPORTANT CHART
http://speakeasy.net/~language/images/graph-freezingpointcomparison.gif



Dynamic Viscosity: (Lower the better) IMPORTANT CHART
low numbers goooood. high numbers baaad.
http://speakeasy.net/~language/images/graph-viscositycomparison.gif



Thermal Differential: (Higher the better) IMPORTANT CHART
http://speakeasy.net/~language/images/graph-differentialcomparison.gif



Thermal Conductivity: (Higher the better)
http://speakeasy.net/~language/images/graph-conductivitycomparison.gif



Thermal Capacity: (reference Thermal Differential chart)
http://speakeasy.net/~language/images/graph-capacitycomparison.gif



the Freezing Point, the Thermal Differential, and the Viscosity are the crutial figures to look at when making your decision.

I'm sorry that these are all on a vertical plane. i tried to make them as easy to read as i could, but with so much information, i had to do them all vertical otherwise they'd run way off into the borders. if you have any questions, feel free to ask.

[o¢r*Aiwa]

These charts are fine, but where is the interest since Redline Water Wetter is afaik superior to all these mixtures.

[r0ckstarbob]

water wetter decreases the freezing point by ONE degree and improves performance in a car up to 15% by breaking up the surface tention. i haven't gone into the issue of additives in your coolant, but basically how it boils down is that additives should be considered just that - an additive, something extra, a way to possibly add a small edge to your performance curve, in the range of 3%-5% - it's not anything you can take to the bank however and doesn't even come close be being "superior" in any fashion of the word. these two topics aren't even in the same ballpark. additives are just that. extra.

heres some good info on waterwetter from the company
http://www.redlineoil.com/redlineoil/wwti.htm

welcome to the forums btw! :)

PS word from the WaterWetter company when i emailed them was to use no more then 5% waterwetter in a computer cooled system without seeing drastically diminished returns in performance.

[r0ckstarbob]

Originally posted by Hachet
Excellent info r0ckstarbob. Thanks for taking the time to post it. I've got a question about the methanol mixture. When it's mixed w/ H20 33/66, is there any chance of this being flamable? Also are there any special considerations in terms of tubing and other gear?
Thanks again.
:D

THANKS!

methanol IS flamable. 100% methanol has a flash point of 12C and a boiling point of 64.7C. Thats pure Methanol though. Mix it with water and that ratio goes rocketing to the bottom. I'm not entirely certain but i'm pretty certain reading in a couple of places where they said that if the amount of Methanol is below 58% or so, then it will not light at all. i'll try to dig up the links.

that being the case, then the answer to your question is "no" a 33:66 ratio Methanol/Water coolant solution will not be flamable.

as far as special equipment, no. nothing in particular. it has no detectable Ph Balance which means that it's non- corrosive but it should be mentioned that it's not dielectric either so you don't want to spill it on your board. something to remember is that it IS thinner then water so you'll want to make doubly sure that your hose clamps are fastened properly and that you have a nice tight fit around the nozzles of you waterblock/radiator to prevent leakage.

let us know how it goes. sounds like you've got a great opportunity to do some intense overclocking!

PS. watchout for condensation! :)

heres the MSDS form for Methanol
http://www.bu.edu/es/LabSafety/ESMSDSs/MSMethanol.html

[Hachet]

Sounds like it's a "go" for the methanol. I should be installing this coming week, I'll keep you posted. I might even do a few hours of running w/ only water and record the temps, then switch over to the methanol mixture and record temps again. Thanks for the link to the MSDS for methanol, that's got some important info.

"PS. watchout for condensation!"

Thanks for tip. I just ordered the Dow Corning Conformal Coating Kit (http://www.octools.com/index.cgi?caller=store/dowcorningkit.html) from octools.:)

[Tiger]

I note so far you have only used organic additives. Since these are all molecular structures they have an affect on the specific gravity and the viscosity of water. They therefore have an effect on the heat conduction since the the additive has different conductive properties to the vehicle (water). Have you given any thought to the use or inorganic salts. Sodium chloride is used in most countries to prevent icing of roads since it reduces the freezing point of water to -17C. There are many salts that don't necessarily corrode. For example try copper sulphate in a copper based cooling system or even silver nitrate. Just a thought, as you may find that there is actually an improvement over water alone.

[r0ckstarbob]

good point. can you come up with or provide any data? that would be some useful knowlege...

it's something i thought about but never looked into very much... we talked about it... there was a thread about it awhile back... in fact it was how i met karsta funny enough...

[Karsta]

Originally posted by Tiger
For example try copper sulphate in a copper based cooling system or even silver nitrate. Just a thought, as you may find that there is actually an improvement over water alone.

Copper sulphate (or some other copper salt) could be excellent idea! I don't know about properties of copper sulphate solution (freezing point at given consentration, heat conductivity etc.) but it is soluble in water and methanol, is not highly toxic (except by ingestion), is a germicide and has beautiful blue color!

Silver nitrate is not so good though, it is strongly oxidizing, caustic (like sodium hydroxide) and highly toxic and a strong irritant.

Edit:
Aluminium would probably reduce copper cations of copper sulphate to metallic copper and oxidize itself. Would this mean that aluminium parts in copper sulphate solution would get copper surface (esp. if current was applied)?

[r0ckstarbob]

copper sulphate huh?

i'm on the hunt now boys and girls.....

be back in a few days with my findings.

[r0ckstarbob]

okay, hers how it works

copper sulphate aka blue vitriol


is blue
called "copper electrolyte" in its aqueneous form
disolves in water @ 3 kg copper sulphate per 10 litres of water before it hits its saturation point...

unlike me, who's hit my saturation point on this topic. if someone can fill in the gaps here, it'd certainly be appreciated. i'm tapped out and burnt out diggin around for this stuff. if it works, great... if its better, even better. anyone who can provide some data on it would certainly put me in their debt. have just spend the past 6 hours looking and comming up with only what you see above you.

i'm tanked. hope someone can field this, and preferrably give some comparable numbers so we have something to reference it against.

what does it do to the water?
whats the freezing point of a saturated electrolyte mixture?
how does it affect the Viscosity or the Thermal Differential of water? (conductivity as a % capacity)
wheres my beer?

<-------- to bed fer crissakes!

*ugh*

i. am. not. a. chemist. i'm. a. graphic. designer. and. ergonomic. engineer. my. face. is. melllllting......

*karump!!!*

scott hits the pillow

[r0ckstarbob]

so is there nobody out there that can provide some data on copper sulphate?

[Karsta]

Uh, Sorry. I kind of forgot it.

I made a quick search of it with Scifinder but found no articles I could get easily (but there is interesting papers about thermal properties of electrolyte solutions - in russian many of those I'm afraid). I got impression that thermal data about copper sulphate solutions should be available because it frequently used electrolyte. I haven't been to library to make a manual search. I suppose there is table books with this information (didn't find from Handbook of Chemistry and Physics).

[Karsta]

I'll check when I have time. Anyway, I think that salts like copper sulphate can not be used with very low temperatures or that solution would have to be then dilute.

I am still planning my water cooling system. Now I think I will do something more basic - start with cpu block and gather experiences and then possibly go further. I am still not quite aware of all the factors contributing and the system has to be very efficient in long term use (no flash clocking). I made Vcore mod for the KG7R - highest voltage I've used so far is 2.03V which translates to 121W at 1655 MHz. Temperature rose to max 53° with Prime95 with air cooling. That kind of wattages will warm up the water quite efficiently I'm afraid, so I have to find a good radiator. If I add chipset and o/ced GF3 to water cooling it will be about 40W more... (Need more efficient PSU too)

[Tiger]

I found the following article which is highly complex but the end and the table give a lot of the answers. They also explain some of the results you have already. BTW copper sulphate will also stop algae growing in the system.


http://webferret.search.com/click?wf,copper+sulphate,,dbhs.wvusd.k12.ca.us%2FC hem-History%2FArrhenius-dissociation.html,,altavista

[Hachet]

Isn't copper sulphate (Blue Vitriol) also known as sulphuric acid?

[Karsta]

No it is not. Copper sulphate is copper(II) salt of sulfuric acid.

And about link. It is nice article but I think it won't give the answers needed as such. It is true that lowering of the freezing point can be calculated and probably also thermal conductivity and solubility. But it is not quite that simple for real solutions. Also the lowering of the freezing point using only copper sulphate wouldn't be so large.

[Tiger]

The following link will help explain my reference above. Given the formula in this article it would then be possible to arrive at a concentration of solute (dissolved salt) to achieve the desired freezing point. What is important is that calculations are based on the molecular weight and not on arbitrary weights.
http://dbhs.wvusd.k12.ca.us/ColligProp/BP-Elev-and-FP-Lower.html
The following link shows an example of how to calculate;
http://learn.chem.vt.edu/tutorials/solutions/fpdepress.html

[r0ckstarbob]

wow tiger... thats very cool. thanks for the tip. just curiously, can you do the math and give us some results? that level of math is a little beyond my comprehension. i can compare numbers and do a limited amount of conversion and so forth, but after that i'm about sunk.

[r0ckstarbob]

i have this same post over at the [H]ardforums (which incidentally also got stickied to the top over there - YAY) the post is even under the same name and is about word for word the same thing. incidentally this post is also over at the AMDmB forums too.

at any rate, it's been really cool to see the different responses and see the different questions come up. this one is from the [H]ardforums. someone asked about how surface tention and the boundry layer all came into play so thought i'd post it over here for general overall knowlege. i suspect someone woulda asked the question sooner or later anyhow, so perhaps i'm beating it to the punch.

enough babblin. here goes.

PS the friend i mention with the PhD in Chemical Engineering, isn't you Karsta. it's someone who started backchanneling me a little while ago and is also been of great help.

***

Originally posted by Amadon
This is some of the best data I have seen posted on the forums.. ever.
Thanks a million bro.
Although I'm not one to go in for sub ambient cooling, mainly because of the maintinence and that I'm paranoid, my following topic applies to both watercooling without a phase change system or peltier units.. and to the opposite.

The thing that I haven't seen addressed is surface tension.
I know very little about it really. But I assume that it is not caused by air "touching" the water. I DO know that if the surface tension is broken.. say.. with soap, that the water flows more freely over a surface.
Couldn't one conclude then that a lack of surface tension, at least in thin (as in depth) water creates a more favorable viscosity?


I always thought this was probably how water wetter helped.

Tell me if I'm wrong. or onto something.

Amadon

okay this is what i've gathered. this is in part from an extremely helpful friend with a PhD in chemical engineering (whom i've been in correspondence with about this) and is a summary of what i've learned about surface tention and the boundry layer having been put into my own words more or less.

theres surface tention and theres the barrier layer. whats the boundry layer you ask?

when a fluid moves across a non moving surface, there is a point where the fluid comes into contact with that surface. (obviously). we'll call the surface the Block.
when liquid moves over the block, the surface of the liquid reacts against the friction of the Block where they contact one another and the motion on the surface of the liquid slows down or stops at that contact point. this is called the boundry layer.

as we know, moving liquid quickly across a surface is what provides us the best heat transfer performance. when any or all of that liquid stops moving and sits there due to the friction it's encountering, it's suddenly doing a less efficient job. the liquid now composing the boundry layer is relying on normal convection to warm itself up enough so it rises off the block (and thus out of the barrier layer) and to be swept back into the waterflow. it's only when it warms up enough to leave the boundry layer due to normal convection that it's replaced with something cooler and the cooling cycle can continue.

creating a small amount of turbulence on the surface of the block will prevent the boundry layer from forming and thus increase the Heat Transfer potential of your apparatus. this can be achieved by soldering little nubs on the surface of your water-passages or simply by roughing it up with small perpendicular grooves in the surface of the metal (such as with a file or rasp). you can also run a small wire or spring (if the channel is big enough) down the length of your tubing if you're relying on your tubing to provide you with some of your cooling ability. (anyone not using copper piping for this last technique should forget it as rubber/nylon/vinyl/silicone tubing isn't heating or cooling your liquid one way or the other and theres really no point - on a slightly different note, this technique might help you guys with radiator problems looking to grab another couple of degrees of cooling power from it. i haven't tested it, but in theory it should be a decent idea).

basically you just want to find a way to interrupt the water that crosses across the surface of the block to prevent the boundry layer from forming.

summary: the boundary layer impedes heat transfer and it becomes thicker with increasing fluid viscosities.

However, the surface tension is a little different in that it reflects how much a fluid spreads out on a solid surface (i.e. low surface tension) vs beading up on a solid surface (i.e. high surface tension) if you wait long enough (equilibrium). The viscosity will affect how fast(rate)the fluid will spread out or bead up. The surface tension is the property which reflects the fluid's ability to wet a surface.

Even if a fluid has a low surface tension and can potentially wet a surface very well, it is not good for heat transfer if the fluid is too viscous and slooows its speed to wet or be replaced by itself with new cooler fluid
(surface renewal). Thus, even though you need the surface to be wetted (low surface tension) you also need it to be easily replaced (low viscosity).

That's why glycol sucks, incidently, compared to water or water/methanol as a transfer fluid in cooling applications. Glycol finds it specific use when
you need to increase the boiling point as well as use it as a heat transfer medium as in autos.

basically by breaking up the surface tention you're increasing the heat transfer potential of your liquid by making it less sticky to itself. you're essentially making the water more fragile and easier to break up which allows for better turbulence on the surface against the block.

use a combination of the two methods to break up the boundry layer on the block and decrease the surface tention of your liquid and you're rockin like dokken.

basically the boundry layer can be addressed by altering the surface of the block. the surface tention can be addressed by treating the liquid. and both techniques can and should be used in collaboration with one another to recieve the most performance out of your heat exchanger AND your coolant if at all possible.

hope that explains things a bit better.

[Karsta]

Hey Bob -you have a good friend! That was a good and informative writing about surface tension and boundary layer.

About those calculations. That formula holds ideal approximation but if we use it we see the following:
Let's think we have 1 molal solution of copper sulfate pentahydrate (M = 249.69 g/mol) which would mean about 250 g of copper sulfate in 1 liter (1 kg) water -I am not saying that it is possible.
molal freezing point depression constant of water is 1.86 Kkg/mol so we would get 2 x 1.86 Kkg/mol x 1 mol/kg = 3,72 degree depression on freezing point with that 1 mole of copper sulfate. Not much I would say.

[Pepsi]

Great info keep us posted.

[ButcherUK]

Quick Q, are the air figures based on actual air, or on air being assumed to be made up of O2?

[r0ckstarbob]

it's actual breathable, everyday air - not 02. just tried to simplify there.

[r_stripe]

does anyone else smell a hint of smog in that everyday breathable air??? maybe we shouldn't be breathing it.

anywho......Great Data!
im sure glad someone has the time to look this stuff up, because I know I currently dont..THANKS for everything you all have been doing.
:D

[Sutekh]

Copper Sulfate,Pentahydrate aka Cupric Sulfate
Blue vitriol
CuSO4.5H2O - means that it has a crystailc structure that holds 5 water molicules
Molar Weight = 249.68
Density = 2.284
Melting Point (C) (-4H2O) = 110
Boiling Point (C) (-5H2O) = 150


A% = anhydrous solute weight per cent, g solute/100g solution
H% = hydrated solute weight per cent, g solute/100 solution
p = relative density at 20ºC, kg/1
D = specific gravity at 20ºC
Cs = anhydrous solute concentration, g/l
M = molar concentration, g-mol/l
Cw = total water concentration, g/l
(C0 – Cw ) = water displaced by anhydrous solute, g/l
(n – n0) x 10 = index of refraction increment avobe index of refraction of pure water 10^4 at 20ºC
n = index of refraction at 20ºC
Δ = freezing point depression a, ºC
O = osmolality, OS/kg water
S = osmosity, molar concentration of NaCl solution having same freezing point of osmotic pressure as given solution, g-mol/l
ή/ήo = relative viscosity, ratio of the absolute viscosity at 20ºC to the absolute viscosity of water at 20ºC
ή/p = kinematic viscosity, ratio of absolute viscosity at 20ºC to relative density
φ = fluidity, reciprocal of absolute viscosity at 20ºC
T = condosity, molar concentration of NaCl solution having same specific conductance (electrical) at 20ºC as given solution, g-mol
γ = specific conductivity (electrical) at 20C, mmho/cm


ok since the Mods took off html codeing i cant make this look very perty so i moved the spreadsheet here :)unomaha (http://ga2.ist.unomaha.edu/data.html)

(All data taken from CRC Handbook of Chemistry and Physics 56th edition 1975-1976) - i know its an old book but not like these things change any :)

[r0ckstarbob]

thats great man. thank you for that. could you go ahead and break those numbers down into something digestable? lets look at it in this way. can you run the numbers assuming that copper sulphate has been totally saturated in an appropriate amount of water in order to make blue vitriol, and then supply the numbers for the freezing point, dynamic viscosity ratings (cP), thermal conductivity, and the specific heat index?

thanks again mr man.

[Ralphing]

... Methanol is the main ingredient in winshield wiper fluid and is used in chlorine free bleaches, paints, solvents, refrigerants and disinfectants.

I just found this info http://www-personal.engin.umich.edu/~ackleym/mtfm3a.html (here.)

Bob, what do you think? I was surprised at this news... I'm wondering if winshield wiper fluid would be a good alternative.
-Eli

Looks like I won't be able to test out the methanol after all. I realized the mixture I have is 20% gasoline.. Doh!

[Ralphing]

Well, I've spent the last few hours looking at data sheets for washer fluids. It seems most have about a 30-35% ratio of methanol to deionized water.
Here's a typical spec:
BOILING RANGE: Approximately 64.5ºC -100ºC
FLASH POINT: Approximately 101ºF
SOLUBILITY IN WATER: Soluble
VAPOR PRESSURE: 42mm @ 20ºC (methanol)
VAPOR DENSITY: 1.11 (methanol)
IONIZATION POTENTIAL: 10.84 eV (methanol)
FREEZING POINT: Approximately -30ºF

Not the most useful info.
Iwasn't able to find any info regarding heat transfer, but I imagine it's quite similar to the methanol/water 33/66 ratio.
From what I've been reading, it doesn't react w/ anything and has balanced ph.
Seems like it's a viable option.
Anyone w/ more info on this?

-Eli

[Karsta]

Originally posted by r0ckstarbob
thats great man. thank you for that. could you go ahead and break those numbers down into something digestable? lets look at it in this way. can you run the numbers assuming that copper sulphate has been totally saturated in an appropriate amount of water in order to make blue vitriol, and then supply the numbers for the freezing point, dynamic viscosity ratings (cP), thermal conductivity, and the specific heat index?

thanks again mr man.

That freezing point depression value is so little as previously noted that copper sulpahate (or other salts) is not a viable option for your purposes. It means that with 5% solution you have freezing point of -0.594°C which is almost the same as for pure water... If that is not yet saturated solution it will not change much anyway.

[r0ckstarbob]

yeah i figured as much. oh well. anyone tried Coffee/Caffine yet?

i'm being half serious here.
:burn:

[Karsta]

Originally posted by r0ckstarbob
yeah i figured as much. oh well. anyone tried Coffee/Caffine yet?

i'm being half serious here.
:burn:

Hmm...
Some solid organic water soluble molecule might do it. It is just that coffeine has quite limited solubility in water.

Methanol seems to be the best for fully closed system at sub-zero temperatures. Gains are anyway so minimal with any better water based coolant that I doubt its worth exploring.

[r0ckstarbob]

agreed. was thinking of perhaps improving the viscosity of water without impinging upon it's thermal properties. it's not an improvement over using methanol for colder stuffs, but for a normal ambient watercooled system, an increase in the performance of water in any manner would certainly be of interest, no?

i dunno. i'm wandering and rambly today. stuffs bouncin around in my head like wildfire. just one of the million and a half things i was thinkin about..

[Sutekh]

sorry i havent broke that data down, havent had time.

If you could prevent the hydrogen bonding that takes place in water then you could lower the viscosity of the water.(of course the hydrogen bonding is the onlything that keeps the water a liquid at room temp).

I do believe that heavy water (D2O) has almost no hydrogen bonding at all, this should lower the viscosity.

[Sutekh]

ok here is some data I've found on deuterium oxide

Viscosity:
a = 757.9 b = 304.6
where log(viscosity) = a * ( 1/T - 1/b )
viscosity: mNs/m² (mNs ??) T: K

example D2O at 293.15K (20C)
log(viscosity)=757.9 * (1/293.15k - 1/304.6)
viscosity = 1.25
compaired to water which has .83

freezing point = 3.6C

its about 10% heavier than H2O

[Karsta]

I checked D2O about month ago (didn't write about it then) and noticed that it has poorer thermal properties compared to H2O. That data was in Handbook of Chemistry and Physics if I remember right.

[Sutekh]

oh ok i wasnt shure of the thermal properties

[Samzik]

cant u use some kinda oils thats waht electrysity companeies do i think they can hadle some - deg in celsius
and here is a limnk wich can provide some help about future duno if its really good stuff but it seems 2 be its link for the subj i postedmineral oil cooling part 1 (http://forums.overclockers.ws/vb/showthread.php?s=&threadid=47387&perpage=30&pagenumber=1) and part 2 my ideas about subj. (http://forums.overclockers.ws/vb/showthread.php?s=&threadid=48083)

can they really help duno :D

[RoadWarrior]

From what I remember of copper sulphate from advanced level chemistry in High School and from my own messing around with the stuff to copper plate things..... it's not something you want in your cooling system....... Unless it's 100% pure copper.

One of the considerations in a mixed metal cooling system is *reducing* electrolytic action, to inhibit electrolytic corrosion due to the standard potential differences between metals. That's why those water wetter additives are a damn good idea. Copper Sulphate is a DAMN GOOD electrolyte, it will plate steel bearing and aluminum bearing parts with CuSo4 becomes sulphuric acid, and eats at the metallic copper in the system to change back into CuSo4, so you'll have a gradual erosion of copper parts and deposition on non copper parts.

About the only use you might find for CuSo4 is deliberate plating of the bottom of sinks or thermal interfaces with the stuff, using a sacrificial anode, like a bit of cutoff copper pipe.

Now you might like to think you have an all copper system, but what about those brass nipples and fittings, what exactly is in that water pump.......

If of course you have an aluminum based PVC jacketed and piped block, and use a plastic shower head as an evaporative cooler, the aluminum being about the only direct contact metal you have in the system, then you might like to give it a try, but I wouldn't really recommend it.

Common Salt will have similar electrolytic corrosive effects, but is actually LESS corrosive than copper sulphate in this regard, ( half as many ions) and you probably all know how bad common salt is for your car.....

Just trying to save you guys some grief,

regards,

Road Warrior

[SUlfUR-CyCLoNe]

Wow, I remember hearing about rockstar's Core Project a few months ago when I first registered here. It's great to see that he's really going somewhere.

I too have been looking into liquid cooling solutions and from what I've seen in this thread and from the data I've come up with it sounds like a 33:66 ratio of Methanol-Water seems to be the best, even though the thermal conductivity isn't as high as water, it's still pretty damn high, plus you have more headroom on how cold you can go. Now, since it's more viscous would that mean you need a more powerful or less powerful pump if you were to have a full liquid cooling solution (cpu, gpu, north/south bridge, etc.)? Oh ya, have you guys figured out what the best pipes/clamps would be if your using methanol-water to avoid
any kind of leak that could do serious damage?

-SUlfUR

[riprock]

I would not use simple plastic "snap" clamps. I'd go with metal screw clamps (and I am!).

Like "Ralphing" I too have been surfing the MSDS sheets for Windshield Washing Fluid and yes, the typical ratio is 33/66 give or take.

Here's my question: "RAIN-X" makes their own WWF but they add that special Rain-X stuff to it to make the water on your windshield roll off quickly. That stuff basically reduces a windshield's friction allowing the water to not stick to it as easily... as I understand it. So, would that be EVEN BETTER than just a 33/66 mix? Or would the slicky Rain-X cause problems or reduce heat transfer or make evil demons rise from your waterblock?!? What does everyone think?!?

[Ralphing]

Jfyi, I've been running washer fluid for the past week and a half and it's working fine. Temps are around 21 idle and 24 full. Should drop down alot once it starts getting cold out. I've got a 6 gallon res and radiator outside. S

[Tiger]

Just for info I have been running a refrigerator water cooled system for about a week now and have been using a combo of an ethylene glycol antifreeze (33%) and water. Using plain water in an evaporating system I was getting a 10C differential between the coolant and the CPU. Using the glycol based coolant I am getting a 13C differential. This equates to 76% of plain water which corresponds well with the figures in the database. Tomorrow I am going to try a combo of ethyl alcohol and water in the same combo to see what I get. I am not sure if the viscosity of the ethylene glycol is a contributing factor as the flow rate is obviously very much slower than plain water. I will see with the alcohol combo because it has much the same properties as glycol except it has a lower viscosity than water.

[Tiger]

I have tried the ethanol and found that it performs identically to the glycol. Have gone back to the glycol purely because of the smell of alcohol that had invaded the whole house and the sincere objections from the rest of the family.

[Karsta]

That's good information Tiger! I won't try ethanol then as antimicrobial agent when done with my wc system.

[riprock]

I haven't ordered my new mobo and chip yet, but I should have all my water components today.

I'll put them together today or tomorrow, if I get them all, and I plan on running washer fluid which is 30% methanol 70% de-ionized water.

A local convenience store chain had contact info for the co that makes their fluid so I contacted them and they said washer fluid ratios vary by location. Here in Kansas the ratio is generally 30/70. Where it's colder it can be as much as 40/60 or 20/80 where it's warmer.

[BrainLifter]

If you goto http://www.csa.com/copperdata and do a search for Copper sulphate

it'll bring up a document called "THERMODYNAMIC PROPERTIES OF COPPER SULPHATE" (it's like the second doc listed)

Only problem is that the doc must be home delivered (not available online) and I'm not sure but I don't think it will help because it looks like a med doc to me.... but it still might help

[Strangelove]

Has anybody given any thought to the conductivity of copper sulphate?? I mean we use distilled water to minimize corrosion and as a small safeguard should the system leak and spill on to our system. If we were to dissolve copper sulphate into our water, it will conduct electricity, like nothing you have ever seen. (The first batteries were made with a copper and zinc solution aka galvanic cells.) We also have to think of how much salt we dissolve, if our cooling system one day goes banana and starts cooling more than it usually does (cold day?) the salts might start going out of solution and my guess is that that would be baaad!

Just a thought

Dr. Strangelove

[Tiger]

Originally posted by Strangelove
Has anybody given any thought to the conductivity of copper sulphate?? I mean we use distilled water to minimize corrosion and as a small safeguard should the system leak and spill on to our system. If we were to dissolve copper sulphate into our water, it will conduct electricity, like nothing you have ever seen. (The first batteries were made with a copper and zinc solution aka galvanic cells.) We also have to think of how much salt we dissolve, if our cooling system one day goes banana and starts cooling more than it usually does (cold day?) the salts might start going out of solution and my guess is that that would be baaad!

Just a thought

Dr. Strangelove
I think that with the calcs copper sulph is not an option because it will not give much in the way of depressing freezing point.
If the system goes bananas, which is unlikely, the result will be ice. Cannot pump ice through tubes unfortunately.

[Tiger]

Have been doing a lot of study on refrigeration and came across stuff on chiller solutions, as they term them "brine", used in air conditioning systems. The two most commonly used are Calcium Chloride where temperatures of not less than -18C are used and Sodium Chloride 23% for temps down to -22C.

[quadrophenic]

just out of curiosity i was wondering how hard these different substances are on plastics and pumps and such... any info is appreciated...

[Phugbox]

amazing thread, good to know, even though I'm not doing WC I'm still happy having read the three pages

good on you all

[ButcherUK]

Originally posted by Tiger
Have been doing a lot of study on refrigeration and came across stuff on chiller solutions, as they term them "brine", used in air conditioning systems. The two most commonly used are Calcium Chloride where temperatures of not less than -18C are used and Sodium Chloride 23% for temps down to -22C.

Brine would be saltwater. Sodium Chloride is normal salt that you might buy at a store. I wouldn't use this in a water cooling system as it's an excellent electrolyte (high corrosion potential) and is likely to leave residue too.

[Kryten]

awesome thread just wish I spoke chemical geek language to understand it, its still nice knowing that should the need arise their are people in the forum with the answers.
great work. 2 thumbs up

[Samzik]

how u think to isolate the water wich is in air when u freez the cpu. i had a friend hes idle temrature was -35 not with water though, he used gas called freon but he had problems water condesaiting to cpu and mobo, wich finaly killed hes cpu he got high results though. 600 cel @ 1.2 gig last 200 mhz didnt give any perfomance though.

[Tiger]

Originally posted by Samzik
how u think to isolate the water wich is in air when u freez the cpu. i had a friend hes idle temrature was -35 not with water though, he used gas called freon but he had problems water condesaiting to cpu and mobo, wich finaly killed hes cpu he got high results though. 600 cel @ 1.2 gig last 200 mhz didnt give any perfomance though.
Well the answer lies in really good insulation.

[Computer Ninja]

This might be a silly question, but where do I find methanol at? Thanks.

[voodoochile]

I noted your chart had 50% hydrogen peroxide (H2O2) in the list. It should be noted that handling and using this is EXTREMELY dangerous. Hydrogen peroxide of that strengh is an extremely good oxidizer. It can ignite when in contact with many organic materials (cotten, human flesh, etc). Some metals are catalists (for example silver) and will cause it to instantly degrade to water, oxygen, and heat. The water will be in the form of hot steam.

FYI, the first rocket powered aircraft in WWII were H202 fueled (usually using 80%+ solutions)...some didn't even combine it with another fuel, just squirted it thru a catalyst screen and had a steam powered rocket.

The stuff you get at your grocery store is about 4%.

For you kids out there reading this and thinking that high concentration H2O2 may be fun stuff to acquire and play with... don't bother...coming from a previous anarchist hooligan, I can tell you the fun factor isnt worth the trouble and risk involved.

[Karsta]

And in addition: hydrogen peroxide reacts with copper. It is commonly used for corroding copper. I just used dilute solution in combination with hydrochloric acid to remove oxide layer after soldering water blocks. (Actually not so good idea because it left ugly rusty looking surface with powder "rust" which was hard to get rid of - citric acid works better for that)

[reco]

This may be true but if you use a kit from overclockers hideout they have told me over the phone and in the directions that only distilled water can be used alcohol ethelyn glycol (anti freeze) water wetter will eventually damage the punp.

[Starfoxer]

i wish i had water cooling

[WeaponX]

Just a thought.... Copper(II) Sulfate is poisionous.... get some under your fingernail and goodnight :)

I think Methanol is the stuff that we like to drink. I wonder how wine or vodka would work...

[Tiger]

Originally posted by WeaponX
Just a thought.... Copper(II) Sulfate is poisionous.... get some under your fingernail and goodnight :)

I think Methanol is the stuff that we like to drink. I wonder how wine or vodka would work...
I think you got your alcohol's mixed ( and not a cocktail either) methanol (as opposed to ethanol which is what you drink) is really dangerous stuff and makes copper sulphate look like a nice old granny. Copper sulphate is not really that poisonous unless you ingest large amounts of it. Methanol on the other hand is a very sneaky one because you don't have to take it. Just inhale it for a while and the route is straight into your blood stream.
I have tried ethanol (higher post) and its not any better than antifreeze and stinks the place out. Not good!

[Computer Ninja]

Tiger, how the heck do you have yoru temps that cold?

Mine is running at 30C Case Temp and 47C CPU temp when running under a SETI load.

I'm at 12x136 right now. 1.88V

How do you CHILL your coolant?

[Tiger]

Originally posted by Computer Ninja
Tiger, how the heck do you have yoru temps that cold?

Mine is running at 30C Case Temp and 47C CPU temp when running under a SETI load.

I'm at 12x136 right now. 1.88V

How do you CHILL your coolant?
I am running a refrigerated chiller.

[Computer Ninja]

Okay, does that mean your reservoir is regrigerated?

[Tiger]

Originally posted by Computer Ninja
Okay, does that mean your reservoir is regrigerated?
Yes. The details are in the article I wrote last month - http://www.overclockers.com/tips777/

[Computer Ninja]

Thanks a lot. I'll check that article out.

[res0r9lm]

Originally posted by reco
This may be true but if you use a kit from overclockers hideout they have told me over the phone and in the directions that only distilled water can be used alcohol ethelyn glycol (anti freeze) water wetter will eventually damage the punp.
those guys at overclockers hideout must know alot about alcohol.
never heard of anybody using alcohol ethelyn glycol in their car. infact I have never heard of it period. I prefer to use Poly Ethylene Glycol.

[Tiger]

Ethylene glycol is and has been the most common additive to sub-zero coolants for more than 60 years. All the fighter aircraft in WWII used it in their cooling systems. It's manufactured from glycerine (glycerol) which is also an alcohol. I have seen this post and don't really believe that it has a scientific basis to it. Propylene glycol apparantly damages plastics. I have done a search of possible interactions with polyethylene (material used to make the plastic piping) and never found any indication that there is a problem. Most of the submersable pumps have a magnetic drive in them so there is no contact between the drive shaft and the coolant. My pump (a maxijet) looks like it is almost entirely made of plastic inside and the impeller certainly has a plastic coating.

[res0r9lm]

Originally posted by Tiger
Ethylene glycol is and has been the most common additive to sub-zero coolants for more than 60 years. All the fighter aircraft in WWII used it in their cooling systems. It's manufactured from glycerine (glycerol) which is also an alcohol. I have seen this post and don't really believe that it has a scientific basis to it. Propylene glycol apparantly damages plastics. I have done a search of possible interactions with polyethylene (material used to make the plastic piping) and never found any indication that there is a problem. Most of the submersable pumps have a magnetic drive in them so there is no contact between the drive shaft and the coolant. My pump (a maxijet) looks like it is almost entirely made of plastic inside and the impeller certainly has a plastic coating.
glycol is also a sugar

[res0r9lm]

What's the benifits of using Propylene glycol over Ethylene glycol
other than being less toxic?

[Tiger]

Originally posted by res0r9lm

glycol is also a sugar
Its actually classified as a polyhydric alcohol the molecular structure is CH2OH-CHOH-CH2OH. The 3 'OH' groups on each carbon make it an alcohol. It does taste sweet but that is caused by the alcohol group. Sugars are made up of benzene rings with OH group at position 6 on the molecule.

[Tiger]

Originally posted by res0r9lm
What's the benifits of using Propylene glycol over Ethylene glycol
other than being less toxic?
I don't believe there are. It is likely that propylene glycol would actually make thermal transfer worse and I have heard reports that it damages plastic piping. I cannot confirm this since I have not seen any evidence of it. It certainly won't be less toxic.

[res0r9lm]

I thought alcohol was a sugar. atleast you can make alcohol with sugar

[Tiger]

Originally posted by res0r9lm
I thought alcohol was a sugar. atleast you can make alcohol with sugar
Yes sugars (the benzene rings) are broken down using enzymes in a fermantation process with yeast to form ethanol.

[Karsta]

Some notes:
1. Glycol has a formula: CH2(OH)CH2(OH). Formula Tiger proposed is for glycerol. Name glycol is often also used for other alcohols with resembling structure.
2. Glycol a dihydric alcohol not a sugar.
3. Sugar structure does not contain a benzene ring. Sugar has an aldehyde or ketone group which is often in acetal or ketal form (thus sugar is then cyclic - but not aromatic). A sugar has also hydroxyl groups which make it also an alcohol.

[Shadow ÒÓ]

Should I change his member name to Water Boy? LOL

Very impressive friend. VERY!

[res0r9lm]

Originally posted by Karsta
Some notes:
1. Glycol has a formula: CH2(OH)CH2(OH). Formula Tiger proposed is for glycerol. Name glycol is often also used for other alcohols with resembling structure.
2. Glycol a dihydric alcohol not a sugar.
3. Sugar structure does not contain a benzene ring. Sugar has an aldehyde or ketone group which is often in acetal or ketal form (thus sugar is then cyclic - but not aromatic). A sugar has also hydroxyl groups which make it also an alcohol.
so if staches are sugars does that make them alcohol too? not trying to be smarta$$ OR anything just curious.

[r0ckstarbob]

Originally posted by Shadow ÒÓ
Should I change his member name to Water Boy? LOL

Very impressive friend. VERY!

thank you. been off the boards for awhile and i don't get the email notices on this thread anymore fer some reason. have been busy with school and the like. good to see the input by everyone. thank you all who have contributed thus far.

[r0ckstarbob]

Originally posted by Karsta
And in addition: hydrogen peroxide reacts with copper. It is commonly used for corroding copper. I just used dilute solution in combination with hydrochloric acid to remove oxide layer after soldering water blocks. (Actually not so good idea because it left ugly rusty looking surface with powder "rust" which was hard to get rid of - citric acid works better for that)

yup yup - was aware of that. In WWII the nazi's made super fast/quiet/secret submarines that ran on H202 and the first messerschmidts and v2 rockets all ran on it.

of all the substances, hydrogen peroxide was the least realistic and least usable of the substances but at one point i got a hair and said "chuck it, why not?" and ran the specs for it just to see what happened- and it still came up waaaay behind. still, for purposes of comparison, it wasn't bad to have up there i don't think. 50:50 H202 is considered well within the industrial strength category and requires alot of moola and govt permits and safety equipment... more hassle than necessary.

[Karsta]

Originally posted by res0r9lm

so if staches are sugars does that make them alcohol too? not trying to be smarta$$ OR anything just curious.

Do you mean starch? Starch is polymeric glucose and has multiple free hydroxyl groups thus it is also an alcohol. But you won't get drunk by eating starch;)

Alcohol is a compound which has one or many hydroxyl groups (-OH). So sugars, starch, methanol, ethanol, glycol, 2-propanol (isopropyl alcohol), glycerol, phenol etc. are also alcohols. Many of those are poisonous, even lethal - only ethanol is suitable for drinking, sugar and starch for eating:p Something being an alcohol just tells that there is one or many hydroxyl groups which can give some information about reactivity or behaviour of the compound in question.

Edit: forgot to mention that the hydroxyl group has to be attached to a carbon atom. So water or hydrogen peroxide are not alcohols. Also hydroxyl group can be part of an another functional group like carboxylic acid (for example acetic acid CH3C(O)OH) then it is not classified as an alcohol but according to the functional group it is part of.

[Dragoncat]

Thanks for the iformative info!!!
( I found it very interesting!! ) Thanks!!!
where can I find out more about water and other liquid cooling systems, and where can I get water cooling or water methane cooling apparatus for my computer system at "rock- bottom"
"aka" "poor man's" price range???
PLease send me some info on where I can get said equiptment at the absolute lowest cost please to: drgncat@humbolt1.com...
Thanks again!!!:)

[ac3wooddog]

cool!

[RACEOMATIC]

Thanks for doing all that hard work for us.

[Tiger]

here is useful graph of viscosities of antifreezes at various temps;
Freezium is a European product which is not available in the USA but if you are interested in it then their site link is here (http://ic.kemira.com/productdetail.cfm?id=149)

[MrRealityman1]

don't they use ammonia to cool ice rinks and bobsled tracks?

[res0r9lm]

I don't know but I do know they use it for industrial refrigration. it's not the stuff you get in bottle to clean with that stuff is only just a few percent while the stuff your talking about is pure very bad news if there is a leak.

[Soren]

great sticky.

I just wanted to thank all who put work into this!

:beer: :beer: on me

[Pla]

:eek: Great data in one place!

I have a few comments. :D
1) The air is mostly Nitrogen (N2) - about 80% (not sure for the exact percentage), and only 16% Oxigen (O2). So you should check the properies of N instead of O2.
2) About the Gold. As you notice from your table it is third compared by heat conductivity. So if you are looking for good heat transfer by solids, heat conductivity is what matters the most and not heat capacity. Heat capacity matters mostly for liquids becase of the way they are used for heat transfer.
(The liquid collects energy/heat by increasing its own temperature, then flows and then releases enenrgy at different place. Since solids are not likely to be moved their heat capacity is not that important.)
So Silver should be the best for heat transfer.

:cool:
Thanks for the data.

[RoadWarrior]

Hmmmm back to copper sulphate and other salts, although they would promote electrolytic action, and their thermal properties in a regular solution suggest no particular benefit in using them, beyond a slight lowering of the freezing point, which can be bettered by other things in solution, there is another angle to these that I discovered recently....

When they dissolve in water they absorb heat energy from the water. Now this is not a particularly startling revelation, until one remembers that warm water absorbs salts better and cool water dissolves salts worse. Therefore if one plans a system carefully, one can build something akin to a heatpipe using the dissolving and reformation of crystals to help transfer heat. However, this means there is some partially solid matter circulating in your water system. If one can find the right balance however one could arrange matters such that the pump is right after ones block and all the salts have dissolved in the block. Quite extreme cooling may however be necessary for the salts to come out of solution at the cooling end, probably better than a radiator could do for instance, unless your hot side is very hot.

I keep thinking a bong or water tower would be a great way to bring the salts out of solution, but you would probably require a filter on top to stop salt dusts being blown out of the top. However, a "naturally aspirated" water tower without forced air would probably not require this. Or a tall unit with light airflow may not find this necessary either. Depends how severe your blower is. A bong that is constantly topped up with a valve or water trap would be the best here to keep the same amount of water in the system and be able to judge better the amount of salts needed to achieve a saturated solution at the water block and an oversaturated solution at the cooled end with crystals coming out of solution and being carried into the waterblock in suspension. You would also have to streamline the flow out of the bottom of the bong so that the salts did not collect at the bottom, you'd basically want a funnel feed out of the bottom or similar.

It goes without saying that you shouldn't attempt this in any old system due to electrolytic problems, and should design the system to avoid this. Electrolytic problems should be possible to avoid somewhat by bonding all metal parts to each other electrically with wires though.

Anyway, that's another angle on what use salts such as copper sulphate or calcium chloride could be in a cooling system.


Road Warrior

[Karsta]

Actually copper sulfate has an additional advantage: it is antimicrobial. It is for example an effective algiside in lakes and swimming pools.

I was thinking of using it for that purpose but then I noticed that it precipitated fabric softener (or rinse I'm not sure about right word) I use now for lowering surface tension and as an antimicrobial agent (not sure if it works).

[r0ckstarbob]

just an update

just had a pretty interesting conversation on Viscosity and it looks like i was mistaken and compared the wrong kind of data - should have compared Kinematic Viscosity instead of Dynamic Viscosity. so here is the chart for the same chemicals with the Kinematic Viscosity figures. i've also included what he told me about it and why it's important for all you real gearheads out there. his name is EMC2 he knows a thing or two about this.

Ok, here goes

Ok, first I'll agree with you regarding methanol and water being much better for the liquid side of the cooling equation of computers from a thermal standpoint.

Hmmmm... where to start regarding the rest... too much for one post

Note: all comments are geared towards the cooling systems at hand - low viscosity, low temperature, newtonian fluids. (the term 'low' being relative - temps under 80C and viscosities such that the liquids are considered "thin" compared to "thick" fluids like oil)

* and the winner is *


Viscocity


The kinematic viscosity is the important value Dynamic viscosity alone is of lesser importance.

First a little piece of info you may not know. Kinematic viscocity and Dynamic viscocity can be related to one another through a material's density. Here's the relationship:

Kinematic viscosity v (Greek letter nu)
Dynamic viscocity u (Greek letter mu)
Density p (Greek letter rho)

v = u/p


In the case of thermal designs using liquid, there are 3 important and inter-related issues:

The Reynold's number (an indicator of flow type - from fully laminar to extremely turbulent) for the fluid flow - this affects directly both the frictional losses and the film coefficient.

Frictional losses through the system - this affects the final mass flow rate (which subsequently also affects the velocity of the flow).

The Film Coefficient (also called the convection heat-transfer coefficient) - in this realm, a measure of the heat transfer between the fluid coolant and the solids it passes through (both block and rad in this case).


Here are the fluid characteristics which are used to calculate each of these 3 very important values:

Reynold's Number - this is a dimensionless number (no units of measure associated with it) that is a relationship between the inertial forces and the viscous forces in fluid flow. The characteric of the fluid used to calculate this number is the kinematic viscosity.

Frictional losses - the number of friction factor correlations in unreal, but - they all use the same flow properties, the differences are in how they handle the geometry of the channel the fluid flows within.

For laminar flows, it's pretty straightforward - it depends only on the Reynold's number. For turbulent flows, it depends upon both the Reynold's number and on the surface features and geometry of the channel the fluid flows through. No direct fluid properties are used - these are taken into account through the use of the Reynold's number.

These frictional losses are usually discussed in terms of head and are what determine what the flow rate through the system is for a given pump. The flow rate of course also determines the velocity of the flow at any point in the system.


Film coefficient - this is the 'ultimate' value that determines the heat flux from the solid (water block in this case) to the fluid flow and from the fluid flow to the solid (heat exchanger, radiator, heater core). The basic equation for the heat transfer is as follows:

Q/A = h * (Tw - Tf) where Q/A is heat flux per area, h is the film coefficient, Tw is the Wall temperature, and Tf is the Fluid temperature.

The film coefficient is calculated from the following characteristics of the fluid flow - the thermal conductivity of the fluid, the Reynold's number for the flow, and the Prandtl number (another dimensionless value that characterizes convection - it relates the hydrodynamic and thermal boundary layers, linking velocity and temperature and is equal to the kinematic viscocity divided by the thermal diffusivity).


Hopefully, you can now see why kinematic viscosity is the "important" viscosity as it were .

low numbers are good.

http://speakeasy.net/~language/kinematicviscosity.gif

enjoy

[SmogFighter]

My Brain is fried!! :eek: :eek:

Thanks to everyone who contributed... my HSF sucks (blows)
anyhow, so it's off to the junk yard to find an old 'fridg.
I have kicking around the idea of making a cold plate for my
500 K6/2. ( I have a limited knowlege of auto referigeration,
so it shouldn't be too hard... What?!? No carburetor?!?!) :burn:

Edit: Have been kicking around...

[Lord_of_Decay]

WOW, that was some reading. Great article filled with alot of great information.:D Having decided to go with water cooling I am looking at using the Methanol/Water mix. From this article and from what others have told me it appears to work the best. I will have to make a trip to my local Automotive store and pick up some Windshield Washer concentrate.

Wish to say thanks to everyone that took the time to do the research for this article.:beer:

[DualP3Power]

Just what I needed. Thanks! :D

[Stephen Castles]

err the servers for the main charts are down...........

[r0ckstarbob]

Originally posted by Stephen Castles
err the servers for the main charts are down...........

i moved the images to a new server - all should be kosher now. sorry for the delay

RSB

[rebelrage9]

Hey I just finished reading the entire post and was able to follow 80-90% of it (good for it being 0145 hours; not to mention I graduated from high school less than a week ago).

I just wanted to say great job to everybody.

I would like to know what everyone thinks is the best solution for a basic water cooled system (High quality [but not solid gold] :) , no TECs, no refrigeration, etc.) by means of the cooling liquid.

I have pieced togeather what I think was the general concensious, but won't state it here to adviod mudding the waters.

I am intrested only in performance, but in overall 'bestness' taking into account such factors of easy to aquire, price, germicide, matience, etc. ALL THINGS CONSIDERED.

Please also included suggested ratios and source of substinance (eg. to use a 99:1 ratio of the ****** - water solution. You can find it in windshield washer fluid in auto part stores.)

I am nodding off while writing this, so if any of the horrible mispellings or inchoherent thoughs need clarifacation just let me know, and thank you in advance for your opinoins.

Adam

[r0ckstarbob]

distilled water and a little bit of redlines water wetter.

or

33:66 ratio methanol/water windshield wiper fluid

[rebelrage9]

Cool thanks for the suggestion. I know you guys are probably burnt out about this, but it is hard for a newb like myself to compile all of this great info into a single "best" solution for the adverage person with a MP config intrested in mild moderate overclocking.

Any body else care to throw there simplified suggestions out here again for us slow ones?

[Despotes]

Methanol/WS wash fluid is an anti-algaeic/bacterial agent that will eliminate the possibilty of "scum" in your system??

[copyman]

epox 8k3a+ (mp1800+) 2033mhz / vcore 2,24v / rock solid / memos 214 mhz

temp idle = 28º / full burn = 39º / ambient temp 19º

project = www.watercooler.com.br


http://www.watercooler.com.br/imagens/watercooler/dsc00011.jpg

pcmark 2002

http://service.madonion.com/compare?pcm=407559


Sandra results


http://www.watercooler.com.br/arivaldo/imagens/imagem.JPG

http://www.watercooler.com.br/arivaldo/imagens/imagem%20memo.JPG

http://www.watercooler.com.br/arivaldo/imagens/imagem%20temp.JPG


this Brazilian waterbloock has temperature reduced in die 6º C less than inoovatek rev3

http://www.watercooler.com.br/arivaldo/imagens/DSC0001.JPG


The reason to envoy this informaciomations and my experiences about watercoolers in this fórum is because I want to effiency’evaluatation that help me to do a better job with watercoolers.
If you know some system similarity or better, I wish you show me to research and improve my system.

[Mikoto]

Don't know if this will have any value to you but saw this t'other day.

http://www.techtransfer.anl.gov/techtour/nanofluids-summary.html

[MEAT BAG]

im a nut

[Ro]

Warning! Long post! (I thought I'd better put this at the top). I hope this issue hasn't long since been taken care of...

Has anybody used methanol yet? And more importantly, are they still alive and if they are, can they still see?!

Sounds like it's a "go" for the methanol. I should be installing this coming week, I'll keep you posted. I might even do a few hours of running w/ only water and record the temps, then switch over to the methanol mixture and record temps again.

I havn't seen a post from this guy since :eek: (I haven't really been looking though)! Are you still ok Hachet?!

Seriously though, I would have thought having methanol in your room/enclosed area is a bad idea. I'm thinking of using ethanol instead (read nontoxic!).

I thought about using methanol, and it appears to be a good deal better, but I want to go to bed at night knowing that there's a chance I'll wake up again! Just reading this MSMethanol.html (http://www.bu.edu/es/LabSafety/ESMSDSs/MSMethanol.html) ensured I wasn't going to attempt it!

Am I over reacting here? Everyone else seems to think it's fine. These things jumped out at me (from that MSMethanol.html) though:

1. I think 200ppm is the exposure limit. This seems low to me.

2. It's boiling point is about 65c. This seems low to me.

3. It's evaporation rate is 5.2. This seems high to me (i haven't a clue really).

4. The two previous points makes me think there will be plenty of vapour about (depends on what the air is like about your area, I suppose).

5. Density of 1.1 (Air=1). It's heavier than air. To me this means vapours concentrating at gound level (and not going up and out the window you left open for them. That's the thanks you get!)

6. Inhalation : May cause respiratory tract irritation. May cause visual impairment and possible permanent blindness. This, coupled with the previous points should be enough to make any non-blind, 'respiratory tract intact' person stop right there (Blind people with an already suspect respiratory tract, knock yourselves out). But wait, there's more!

7. May cause effects similar to those described for ingestion. Really? And what effects might that be...

8. Well let's see, Ingestion : May be fatal or cause blindness if swallowed. May cause irritation of the digestive tract. May cause kidney damage. May cause systemic toxicity with acidosis. May cause central nervous system depression, characterized by excitement, followed by headache, dizziness, drowsiness, and nausea. Advanced stages may cause collapse, unconsciousness, coma and possible death due to respiratory failure. "Oh. That 'death' thing seems particularly nasty." Yes, it is. Even if you don't drink or inhale heavily there's always...

9. Chronic [exposure] : Prolonged or repeated skin contact may cause dermatitis. Chronic inhalation and ingestion may cause effects similar to those of acute inhalation and ingestion. I don't need to reiterate what 'acute inhalation and ingestion' can lead to, do I? 'dermatitis' - I don't know what it is, but I know I don't want it!

10. 'nuff said.

On the other hand, you can actively engage with ethanol purity testing with a few friends! :beer:

"Save lives - don't use methanol. (You'll save yourself for a start, and perhaps your unsuspecting cat aswell)."

Later,
Ro

[res0r9lm]

eithier one you would want a closed system. dermatitis isn't that dry skin? http://www.mayoclinic.com/invoke.cfm?id=DS00339

[Ro]

A closed system is a good idea for both methanol and ethanol. Still, I'd much rather be cleaning up an ethanol leak than a methanol one.

Anyway I was thinking of using ethanol for my system. But given the data on this post, ethanol is worse at transfering heat than water. So what about some ethanol-water solution?

This site Colligative Properties: Freezing Point Depression and Molecular Weight (http://www.vscc.cc.tn.us/academic/math/CHE/122/Labs/Colligative.htm) seems to have some formulas for calculating what would give the optimum ratio. I want as much water in the solution as possible, without the solution freezing. I'm going to use a chest freezer for cooling the ethanol-water, so that means having enough ethanol to keep the freezing point below about -20c.

Or maybe I should be just looking for anti-freeze? I was betting on the ethanol, 'cause I thought it might allow for much lower temperatures. If I tamper with the freezer's termostat, will the freezer stay on and keep cooling down to -50c, or something? Or is it determined by the refridgerant in the freezer?

Later,
Ro

[res0r9lm]

Originally posted by Ro
A closed system is a good idea for both methanol and ethanol. Still, I'd much rather be cleaning up an ethanol leak than a methanol one.

Anyway I was thinking of using ethanol for my system. But given the data on this post, ethanol is worse at transfering heat than water. So what about some ethanol-water solution?

This site Colligative Properties: Freezing Point Depression and Molecular Weight (http://www.vscc.cc.tn.us/academic/math/CHE/122/Labs/Colligative.htm) seems to have some formulas for calculating what would give the optimum ratio. I want as much water in the solution as possible, without the solution freezing. I'm going to use a chest freezer for cooling the ethanol-water, so that means having enough ethanol to keep the freezing point below about -20c.

Or maybe I should be just looking for anti-freeze? I was betting on the ethanol, 'cause I thought it might allow for much lower temperatures. If I tamper with the freezer's termostat, will the freezer stay on and keep cooling down to -50c, or something? Or is it determined by the refridgerant in the freezer?

Later,
Ro
The ethenol/water mixture would have better heat tranfer and would have more viscosity. I think you should also take into account the thickness of the mixture once it's at those low temps.
Maybe a combination of the three.

[kickb0xer]

cabt see pics..just an outline with red x...am interested in watercooling...and please please some one tell me quickly which way to go..AMD<--prvious owner and big fan or the new intel... and which vendr is most respected on PRICEWATCH i see Accubyte alot, if i buy something i want a reliable company not a con... my goal for a pc system is at least 2100xp 333chipset with pc2700 aka ddr333 mem... or a 2.2 pentium, and what mother board? epox i have heard good things also the ECS k7vta3.v 3.1 looks impressive for what it is please help on all issuses for he who is GOD of O/C lol

ALSO my budget is 500 i already have my HD, floppy, ti4200 vid and 19 crt..monitor, need a barebones basically..

[Kaneda]

awesome, very informative!

[000]

I've been wondering about the methanol toxicity question also. If you have an open system (which I imagine alot of the water chiller people do) is it really a wise thing to use?

Now about Ethanol:

Ethanol will keep the viscosity much lower than antifreeze, which will definately help pump it at -20c (antifreeze gets pretty thick at -20c), but Ethanol's heat transfer capabilities look to be poor.

Since Ethanol does have a lower freezing point you wouldn't have to use as much of it in a mixture of water to equal out Methanol, can anyone put some graphs up comparing a methanol-water vs ethanol-water vs antifreeze-water where they have freezing points at about -34 ? Ethanol seems like a much safer thing to use, just dunno how good it is.

Thanks,

-Sidney

[Tifosi]

Having not read every reply to this thread, (sorry), but going through the entire article from the main site, I'd like to add just a small bit of information to the methanol/water mix and its combustability.

This information is taken directly from personal experience in racing.

1) methanol burns competely clear. (you won't know it til you see something discoloring from incineration, or you feel it cooking you)

2) very small amounts of water mixed with methanol in a fuel cell can produce BETTER combution when compressed. (methanol makes more power by combusting slower than gasoline, therefore it pushes the piston for a longer period of time once ignited. Water, in VERY small amounts can extend this burn time)

3) the more water added to methanol, the less "naturally" combustible it becomes. (you need to atomize and/or compress it more to attain any sort of combustion)

4) methanol is utterly toxic and deadly to life forms as we know it. If as little as a 1/4 teaspoon gets ingested into your system, you WILL die, (absolute best case scenario in that event you don't die: you will be blinded permanantly from alcohol poisoning). Even a couple drops in your mouth is enough to give you the pukes for a long period of time. (don't eat the coolant/fuel if you construct a system cooled this way) oen wound contact usually isn't an issue other than the really nice burning sensation it gives.

5) methanol fires are extinguished with WATER extinguishers, NOT chemical or foam types, (these can just spread the fire, or not efficiently extinguish it). Keep a water container around for just that purpose when uncut methanol is being worked with. Do not attempt to smother the fire if you catch a sleeve or other loose clothing alite, drown it in water. (at times when burning, methanol can create a highly dense alchol vapor, this can actually seep into the smothering item and create a torch, complete with spontanious combustion)

6) the more water dominant mixes are definitely safer, as described in the article, but under compression and if there is a chance to create any kind of vapor area, there "may" be risk. If there is a non-moving air pocket in the system for example, and enough heat gets generated to vaporize some methanol. (you would still need a spark of some type to set it off, but then again you ARE working inside an electronic device........)

7) don't pay more than $3.25 for a gallon of the stuff. :) (you can readily get it at most of the performance karting shops, places that build some classes of dragsters, and most chemical distributors)

I'm not trying to scare anyone away from this type of cooling, in fact I'm looking at trying it myself. I just wanted to pass along some potentially useful information that could keep some folks out of trouble if they knew ahead of time. (ever meet that guy who feels he needs to siphon everything to purge the system?)

Tape your mouth shut, don't huff the fumes, don't wear baggy clothes that may get soaked/wet from indavertant contact, and keep a bucket of water handy. Once the stuff is mixed, the system purged, and some evaporation time is given for the "outside" stuff that may have gotten splashed on, you should be golden . (and all that from just racing that type of engine out on the track! See, the world DOES cross reference itself at some point or another........ LOL)

[fletch]

specific heat of a liquid also makes a big difference in cooling as it can directly affect the rate of heat transfer

[r0ckstarbob]

Originally posted by 000
I've been wondering about the methanol toxicity question also. If you have an open system (which I imagine alot of the water chiller people do) is it really a wise thing to use?

Now about Ethanol:

Ethanol will keep the viscosity much lower than antifreeze, which will definately help pump it at -20c (antifreeze gets pretty thick at -20c), but Ethanol's heat transfer capabilities look to be poor.

Since Ethanol does have a lower freezing point you wouldn't have to use as much of it in a mixture of water to equal out Methanol, can anyone put some graphs up comparing a methanol-water vs ethanol-water vs antifreeze-water where they have freezing points at about -34 ? Ethanol seems like a much safer thing to use, just dunno how good it is.

Thanks,

-Sidney

sorry man, someone else will have to compile that data for you, but essentially i've provided all the information you would need to answer that question by yourself in the graphs... it's what i would do to answer it. while not 100% accurate, the changes with temperature and mixture are relatively linear so graph the data, draw a line and predict...

good luck


and to answer alot of questions and save alot of headache, has it been mentioned that there are several brands of windshileld wiper fluid on the market that are nothing more than a 70:30 water-methanol mix with some blue dye thrown in.

(no the dye is not harmful to computer components)

thought i'd mention it.

[sappo]

your overall thermal differential does not work because it assumes that heatsinks of the same weight (not size) are being applied to the cpu. you need to multiply the differential by each metals’ weight density. this would make gold an even better in comparison, which brings up mistake #2: i'm almost positive there isnt a direct relationship between conductivity and heat capacity. think about it. as long as my heatsink's material is close to the same temperature as my cpu slug, i could care less how much energy it takes to raise my heatsink’s temperature. a diamond has a heat transfer ratio 10X better than gold, but it takes about 10X more energy to raise the temperature of a portion of equal volume. Which would you rather have? diamonds are so efficient at heat transfer in fact that they actually are used in high tech manufacturing processes for heat transfer despite their HUGE pricetag!! gold isnt. dang it, if diamonds werent a girl's best friend they would surely be an overclockers best friend. Hmmmm…... diamondddd…..

a diamond would annihilate copper too. in fact, I think that heat capacity may even be NEGLIGIBLE in the heat conduction of solid metals. In liquid cooling applications, would adding twice as much water (to simulate heat capacity increase) work as well as pumping the water twice as fast (simulating heat conduction)? Basically, heat capacity only acts as a buffer, but once the cooling material (be it liquid or metal) is heated up during full load, it no longer matters.

Assuming a copper heatsink weighs 300 grams and it is raised from a room temperature 25C to maximum full load temperature of 40C it would only take 1740 joules for the change in temperature, assuming no heat is dissipated along the way (.092 calories/gram X 4.2 joules per gram X 300 grams X 15C). an 80 watt cpu will give off 1740 joules in about 20 seconds. of course, along the way it will dissipate some heat, but the heat capacity’s “buffer” obviously isnt very long.

it makes sense to me that once the maximum temperature is reached, heat capacity has little to offer. i suppose that you could advocate the benefits of a larger reservoir in liquid cooling, but even then, it’s probably more efficient due to the larger surface area of the coolant as opposed to the larger heat capacity.

with air-cooled heatsinks, the real bottleneck is convection into the air. i think it would be interesting to test two identically dimensioned heatsinks with identical heat transfers that differ greatly in heat capacity. the results may be surprising.

another VERY IMPORTANT thing to keep in mind is that with liquid convection/cooling, the thermal conductivity of the liquid wont matter very much if it is being pumped through a block that offers little surface area. i suspect that a very large bottleneck in liquid cooling is actually the block itself. people tend to overlook this. most of the time they make a couple round tubes for liquid to flow through. granted, it is MUCH easier to machine a copper block that way, but do air-cooled heatsinks have a couple drilled holes for air to flow through. heck no!! i bet if i increased the surface area inside a block by 5 times, i could use whatever liquid i wanted and it would still be better than water.

one more thing, water isn’t the best thing for liquid cooling. mercury is. its melting point is -40C and is almost 14X more conductive than water. it would be extremely difficult to use (although i still think its possible), but i think these qualities alone at least make mercury deserving of lip service.

eric

[r0ckstarbob]

Originally posted by sappo
i bet if i increased the surface area inside a block by 5 times, i could use whatever liquid i wanted and it would still be better than water.

um, yeah, okay. do it. using water in the same system will still do better than anything else you can afford to put through there. you're not thinking in whole systems, you're only thinking in pieces. if you can increase the surface area inside a block by 5 times, the water will ALSO perform that much better.

one more thing, water isn’t the best thing for liquid cooling. mercury is. its melting point is -40C and is almost 14X more conductive than water. it would be extremely difficult to use (although i still think its possible), but i think these qualities alone at least make mercury deserving of lip service.

eric

am pretty sure we covered all these points earlier on in this thread. yes theres a relationship between the specific heat and the conductivity of an item - yes it's called the thermal differential. yes there are several ways of determining the thermal differential. for the purposes of a direct comparison, i picked a fixed point and ran my comparisons appropriately. the focus of this research was to create a relative comparison between the substances that we most often use (or fantasize about using) and provide some data that was relevant to us.

yes we all know that mercury is pretty good at heat transfer but there are some really obvious and incredible reasons for not using it... the fact it's one of the most toxic substances on earth being one of them, the fact that it expands and contracts... the list goes on and on... diamond is obviously so prohibitively and pointlessly expensive... everyone and their mom knows these arguements. neither of these items really matter in the world of practical computer cooling as far as i've ever known, and tend to fall into the speculatively ridiculous to even consider.

so to remain level headed and even keeled, lets just say that using mercury is not the best solution for liquid cooling.

water is the best substance for heat transfer. period. per price, availability, toxicity, thermal performance, etc... when looking at ALL these things as a complete system (and we must), water comes out far far ahead. you cannot take one element out of the basket and make a blanket statement encompassing an entire field of study and consideration. you must consider the whole of the problem, or what you're engaging in is only so much disproportionate mental masturbation.

want a best to worst setup for coolants at all temps? its this.

#1 66:33 ratio water/methanol windshield wiper fluid at all temps actually does better than just plain distilled water, though not by much - in truth it's likely you'd be hard pressed to see the performance increases at above freezing temps, but they are there. open system users should keep an eye out for slightly increased evaporation rates (over water) but all in all you'll probably be pretty safe. increased ratios of methanol to water will not increase performance as it pretty evenly cancels itself out as you go... much better visosity but much worse thermal properties the higher the ratio you go... pretty pointless if you ask me and if your methanol ratio gets too high it becomes a health issue...

#2 Distilled Water and Redlines Water Wetter (95:5 approx ratio) again, hard pressed to find performance increases over straight water, but in theory they're there.

#3 100% distilled water. straight up, can't go wrong.

#4 Antifreeze-water. use as little antifreeze as humanly possible as your performances starts bottoming out when you start adding antifreeze to the mix.


equilibrium. balance. focus. rock on crouton.

happy overclocking and welcome to the forums.

[000]

r0ckstarbob:

I was mainly interested in the viscosity of ethanol as the temperature falls. Unfortunately viscosity is usually not linear with temperature changes.

Also if you know the viscosity of acetone at lower temperatures
~ -20c that would be very helpful also.

Thanks,

-Sidney

[r0ckstarbob]

um, dunno off hand. you're right of course in that these things aren't perfectly linear, but the best you're going to get from the numbers is a pretty solid approximation anyhow. punch visosity and ethanol into google and see what comes up... someones bound to have posted some data on it.

[dmitriyaz]

r0ckstarbob,
sorry to take your time with this stupid question.
if i need the liquid to have good viscosity and thermal differential at -30 degrees, and i WILL NOT UNDER ANY CIRCUMSTANCES use methanol, wouldn't the best solution for me be ethanol/water mix?
antifreeze has extremely poor viscocity, it will eventually kill my pump. thermal differential of it is not the best, either.
distilled water-water wetter will freeze up.
well if ethanol water is not the best solution, what is?
and if it is, how come its not anywhere of your list?
thanks :)

[r0ckstarbob]

Originally posted by dmitriyaz
r0ckstarbob,
sorry to take your time with this stupid question.
if i need the liquid to have good viscosity and thermal differential at -30 degrees, and i WILL NOT UNDER ANY CIRCUMSTANCES use methanol, wouldn't the best solution for me be ethanol/water mix?
antifreeze has extremely poor viscocity, it will eventually kill my pump. thermal differential of it is not the best, either.
distilled water-water wetter will freeze up.
well if ethanol water is not the best solution, what is?
and if it is, how come its not anywhere of your list?
thanks :)

nah man, nothin stupid about questions.

seriously, i have no idea. are you morally/principaly opposed to using windshield wiper fluid as a coolant? i guess if i had to do a quick once over of the data, a 80:20 to 60:40 ratio of ethanol/water should be fine and still better than antifreeze, though i can't give you any numbers at this time to support it. call it a decent bare bones guestimate... bout the best i can do at this stage of things. sorry.

[dmitriyaz]

thanks!
i don't want to use methanol or methanol containing substances because frankly, i'm scared of it.
but i guess this question won't bother me any more,
as i've decided to go with direct dye cooling.
BTW, do you know how much they charge to fill a gehumidifier-sized loop with r134?
thanks again

[sappo]

quote:
um, yeah, okay. do it. using water in the same system will still do better than anything else you can afford to put through there. you're not thinking in whole systems, you're only thinking in pieces. if you can increase the surface area inside a block by 5 times, the water will ALSO perform that much better.

I agree totally, but you missed my point. If you are going all out with all these toxic cooling mixtures, you had better make sure the block is extremely efficient, otherwise, its all for naught.

quote:
am pretty sure we covered all these points earlier on in this thread. yes theres a relationship between the specific heat and the conductivity of an item - yes it's called the thermal differential. yes there are several ways of determining the thermal differential. for the purposes of a direct comparison, i picked a fixed point and ran my comparisons appropriately. the focus of this research was to create a relative comparison between the substances that we most often use (or fantasize about using) and provide some data that was relevant to us.

Well, if youre going to factor in specific heat you should at least be factoring in the VOLUME and not the MASS. You dont fill up a reservor with grams of a liquid; you do it with cc's. Weight should be a variable in your comparisons. Either way though, heat capacity isnt that important (although i think we already all agree on this).


quote:
yes we all know that mercury is pretty good at heat transfer but there are some really obvious and incredible reasons for not using it... the fact it's one of the most toxic substances on earth being one of them, the fact that it expands and contracts... the list goes on and on... diamond is obviously so prohibitively and pointlessly expensive... everyone and their mom knows these arguements. neither of these items really matter in the world of practical computer cooling as far as i've ever known, and tend to fall into the speculatively ridiculous to even consider.

About diamonds, you missed my point agian. It is 10x worse in thermal capacity and 10x better in conductivity. Yet they are vastly different in thier heat dissipating capabilities.

And about mercury, its about like lead. Handle it properly and it shouldnt be a problem. When soft, It is even ok to handle the dental filling material made from mercury, so long as you dont do it everyday. Good grief, pure Methanol has a flash point!

I think the best way to go is to use vodka. its cheap, has a low freezing point, has a low viscosity level, is nontoxic.... But most importantly, you can make white russians with it. Plus, its just plain cool to have vodka cooling computer!!!

[r0ckstarbob]

okay, um.... no.

listen man, i'm not trying to step all over you but you're bustin in here with both guns blazing when what you need to be doing is slowing down a tad and listen to whats being said. you're wrong and you're making contradicting or half formed statements based upon (i can only assume) partial information.

Originally posted by sappo [quote]
About diamonds, you missed my point agian. It is 10x worse in thermal capacity and 10x better in conductivity. Yet they are vastly different in thier heat dissipating capabilities.[/i]

listen, your point is flawed. the reason diamond is such a good material to use for heat transfer is not because of one set of stats or another set, ITS THE COMBINATION OF STATS THAT MAKE IT GOOD. it's this combination of stats that is expressed as it's Thermal Differential.

You missed my point again. If you are going all out with all these toxic cooling mixtures, you had better make sure the block is extremely efficient, otherwise, its all for naught.

well, duh...

And about mercury, its about like lead. Handle it properly and it shouldnt be a problem. When soft, It is even ok to handle the dental filling material made from mercury, so long as you dont do it everyday. Good grief, pure Methanol has a flash point!

the puropse of this study was to look at polar coolants. yes it can be used with standard room-temp systems and yes there is a risk using a methanol based system. that risk is neglegable and with all things that we do in overclocking, the weights of the benefits must be weighed against the negatives when doing anything and then a personal choice must be made. if you're not comfortable using it, fine, don't use it. you don't have the data however to condemn its use because it's a perfectly viable solution with FAR LESS problems then using mercury. afterall, we're talking about a 30:70 ratio of methanol to water to get some really incredible performance. that is a pretty miniscule amount of methanol compared to the water. don't give me some crap about flash point at those ratios - it's not even an issue. nobody should even consider using better than a 40:60 ratio solution unless you plan to go past -50C! hA! fat chance.

personally, if you die because you couldn't put it together enough to handle windshieldwiper fluid without hurting yourself, you deserve to die. pure darwinian here, you deserve to die if windshield wiper fluid kills you (or blows up on you). and good riddance! improve the gene pool, cease to breed. eliminate stupidity through stupidity. it's a self consuming organism.

the idea of using mercury in a computer cooled system is not a good idea. in fact as an idea it sucks. it's utterly toxic, it's prohibitively expensive, it swells to extremes with heat, shrinks to extremes with cold... you couldn't even afford the equipment required to try and make something like that work in a computer system, much less to buy it in a quantity necessary for any kind of practical cooling use.

I think the best way to go is to use vodka. its cheap, has a low freezing point, has a low viscosity level, is nontoxic.... But most importantly, you can make white russians with it. Plus, its just plain cool to have vodka cooling computer!!! [/B]

i'm glad you think so. we're all entitled to our opinions. thank you for sharing your opinion. i'm sure you'll get adequate results and accomplish whatever it is you would like to accomplish.

The facts are that windshield wiper fluid is cheaper, doesn't have an age requirement to purchase, is not at risk of being drunk by your roommate, has a better viscosity level, has a vastly better thermal differential, has no sugars to screw up the works in your pump, and in addition to performing much much better, you can also find it at virtually any autoparts store. now granted it's not as cool as making white russians out of it, but my computer will outperform yours and won't be at risk of being consumed in some fratboy drinking frenzy....

... i can just picture it - shotgunning the computer like a beer bong, someone holding my antec over the face of some jock moron with a hose jammed in his pie hole with the rest of the room chanting "drink drink drink drink!" while my little enheim chugs away....

oh wait, i'm 26. i don't live in a dorm.

whew.

thems the stuff nightmares are made of boy i tell ya...

[safemode]

i'm willing to bet a bunch of us are in university. Do you really think a vodka cooled computer is going to last long in the dorms? you'd better put some water wetter in it to discourage yourself later. Or just dont tell your roomate or anyone what's really cooling it. mmm.vodka


oops almost forgot. Underage drinking is bad...dont do it. Ok, yea.

[glass]

just use denaturated-ethanol to keep yourself from drinking it. that's the only 'pure' alcohol that is available(for normal folks) around here(finland), because of high alcohol tax.. because of this it used to be illeagal to use methanol in wiperfluids (to keep alcoholist bums from dying), but since EU this has been legalized. drinking methanol == bad, you drink enough you die, you drink less, you lose vision, you drink even less and get a HUGE hangover, in every case it's a trip to hospital and better have good luck, these cases happen from time to time, it's one of those reasons why you should know the guy you buy your (illeagal) pure spirits or moonshine. btw, normal alcohol products do have (miniscule) amounts of methanol in them (and this adds to the hangover too), IIRC clear vodka has least, and whiskey has most.

anyways, i wouldn't worry using methanol in closed loop system, you worry when you smell the washer fluid while in car?

[Ct. Strangelove]

wait, are you guys saying i could replace my water in my system with vodka? no seals would be at danger? temps still good? transfer rate high? thermal capacity high? plz explain this vodka thing.....
thx

[r0ckstarbob]

Originally posted by Ralphing
Well, I've spent the last few hours looking at data sheets for washer fluids. It seems most have about a 30-35% ratio of methanol to deionized water.
Here's a typical spec:
BOILING RANGE: Approximately 64.5ºC -100ºC
FLASH POINT: Approximately 101ºF
SOLUBILITY IN WATER: Soluble
VAPOR PRESSURE: 42mm @ 20ºC (methanol)
VAPOR DENSITY: 1.11 (methanol)
IONIZATION POTENTIAL: 10.84 eV (methanol)
FREEZING POINT: Approximately -30ºF

From what I've been reading, it doesn't react w/ anything and has balanced ph.
Seems like it's a viable option.
Anyone w/ more info on this?

-Eli

[sappo]

wait, are you guys saying i could replace my water in my system with vodka? no seals would be at danger? temps still good? transfer rate high? thermal capacity high? plz explain this vodka thing.....

Its vodka man, as far as seals go, I say if your stomach can handle it, so could your watercooling system. Temps are excelent. Ethanol (the alcohol in vodka) has a freezign point of -113C so you wouldnt have to put as much ethanol to your water as you would methonal.

After some calculations, I found some interesting stuff. Supposedly the IDEAL mixture of water to methanol is 66% to 33%. That would give you a freezing point of about -32C. Well, a 29:71 ratio of water to ethonal would give you a freezing point of -32C if my calculations are right*. Since there is less ethonal slowing down the heat transfer, the two mixtures have an extremely close heat transfer ratio. .48 for methanol and .47** for ethanol--a difference of less than 3 percent. Whats more, the ethanol mixture will have a FAR superior viscosity level. The minute difference in heat transfer ratios will will probably be made up because you'll have a faster moving solution with ethonal. Factor in "coolness points" for using vodka-like mixture of 29:71, and an ethanol wins in a landslide.

Luckily the heat capacity (which doenst make a difference anyway) between ethonal and methonal is pretty much the same, so i dont have to open that can of worms.

Actually, when i brought up the vodka thing, i was kinda joking. But now im convinced it's the way to go.. I guess the only problem is fending off all the punks that will steal your coolant.

*0Cx.71%+113C*29%= -32.7C
**.6(watts per cube of water)X71%+.15(watts per cube ethanol)X29%=.47 watts/cube of mixture

[sappo]

r0ckstarbob,

Debunking the thermal differential theory once and for all:

Ok, you say it’s better to have a higher thermal differential. Whereas the numerator is the thermal conductivity and the thermal capacity is the denominator, (or conductivity/capacity). If we're looking for bigger numbers, then you would want your liquid to have a LOW thermal capacity. But thermal capacity is good –you don’t want your coolant to "heat up" quickly. You want it to TRANSFER heat quickly. So why is capacity the denominator? It shouldn’t be.

Well that would throw everything out of whack, right? That’s because it is. That’s what I’ve been trying to say all along. Since both are desirable you should somehow ADD the two together, certainly not divide. Since conductivity is much more important, it should be weighted more heavily. Then your results would fall into place. Gold is not a better cooling material than copper and silver is certainly not twice as good as copper, actually i doubt it’s even better at all. Your results are skewed because your methods were completely wrong.

A second mistake is that you should include density into the equation. Those thermal capacity figures only factor grams. When you fill up a reservor grams are variable. The thing that is constant is the VOLUME. So you'll need to multiply the capacity by the density. I dont think it would make much of a difference because 1) heat capacity doenst really make a difference anyway, and 2), i think all the liquids that were examined differ only slightly in density.

sorry to rain on your parade, but you are wrong wrong wrong. Can i get a witness up in here?!?! *dead silence*

How do you figure a methanol mixture would have better viscosity levels than an ethanol mixture? I could see how a methanol mixture may have a better viscosity than vodka (which i still doubt), but an ethanol mixture is gonna be alot better.
YA BABY! I HAVE EXERCIZED THE DEMONS!!!

[r0ckstarbob]

okay, lets see if i can explain this so you can understand it without blowing a gasket.

Originally posted by sappo
[B]

Its vodka man, as far as seals go, I say if your stomach can handle it, so could your watercooling system.

oh, well since you put it that way, gee whiz, why not?...
if thats not the voice of reason and logic then i don't know what is. that kind of logic is bound to take you far.

note to self: in the future when overclocking, sappo says that if you can put it into your own body, then it can't be too bad for your computer. brilliant. absolutely brilliant.

Ethanol (the alcohol in vodka) has a freezign point of -113C so you wouldnt have to put as much ethanol to your water as you would methonal.

3 things
* you misspelled methanol... and freezing.
* no matter what ratios of ethanol you use, ethanol is THICKER than water which means that no matter what you do, you will ALWAYS have worse viscosity and worse flow if you use Ethanol.
* and while it's true that you wouldn't have to use quite as much of it to beat the freezing point, what you did use would STILL not give you as good of thermal properties had you just used methanol in the first place. see below. you prove my point for me beautifully.

After some calculations, I found some interesting stuff. Supposedly the IDEAL mixture of water to methanol is 66% to 33%. That would give you a freezing point of about -32C. Well, a 29:71 ratio of water to ethonal would give you a freezing point of -32C if my calculations are right*. Since there is less ethonal slowing down the heat transfer, the two mixtures have an extremely close heat transfer ratio. .48 for methanol and .47** for ethanol--a difference of less than 3 percent.

correct, though miniscule, methanol still comes out ahead. thank you for proving my point.

Whats more, the ethanol mixture will have a FAR superior viscosity level.

DEAD WRONG.

methanol is the only thing thinner than water. thinner = better viscosity/flow. ethanol is thicker than water

http://speakeasy.net/~language/kinematicviscosity.gif

How do you figure a methanol mixture would have better viscosity levels than an ethanol mixture? I could see how a methanol mixture may have a better viscosity than vodka (which i still doubt), but an ethanol mixture is gonna be alot better.

every single time you add ethanol to water it's viscosity gets a little worse. period.

again. Ethanol is thicker than water. Methanol is thinner than water. hello?

alternately, every single time you add methanol to water, it's viscosity gets a little better.

Factor in "coolness points" for using vodka-like mixture of 29:71, and an ethanol wins in a landslide. Actually, when i brought up the vodka thing, i was kinda joking. But now im convinced it's the way to go.. I guess the only problem is fending off all the punks that will steal your coolant.

wow, are you for real? you just get more and more screwed up as you go. hoorah for tenatiousness boy but chu're wrong wrong wrong and you just get worse...


r0ckstarbob,

Debunking the thermal differential theory once and for all:

chuckle... you go boy...

Ok, you say it’s better to have a higher thermal differential. Whereas the numerator is the thermal conductivity and the thermal capacity is the denominator, (or conductivity/capacity). If we're looking for bigger numbers, then you would want your liquid to have a LOW thermal capacity. But thermal capacity is good –you don’t want your coolant to "heat up" quickly. You want it to TRANSFER heat quickly. So why is capacity the denominator? It shouldn’t be.

Well that would throw everything out of whack, right? That’s because it is. That’s what I’ve been trying to say all along. Since both are desirable you should somehow ADD the two together, certainly not divide.

listen, i didn't make this stuff up. is it possible i'm wrong? sure. but i'm not. thermal differential isn't just something i whipped up on ths spot to make me feel good and you feel bad. if you don't believe me, go and talk to Dave Smith over at the AMDmb forums (aka Myv65 ---myv65@yahoo.com---) who wrote THIS (http://forum.oc-forums.com/vb/showthread.php?s=&threadid=28876) article that Hoot had stickied right below this post right here.

so what if you had a fluid that had a Specific heat of 3 cal/g C (3 times more than water) and a Conductivity of 0.01 w/m C? (approximately 60 times worse than water)

according to your system of ADDING these numbers together, this mystery fluid would have a Thermal Differential of 3.01 versus that of water which is at 1.6 under your system - according to your system, this mystery fluid could be predicted to outperform water by 3 TIMES as much, even though it conducts thermal energy 60 TIMES worse than water.

not a chance.

if you had a second mystery liquid that had a Specific Heat of 0.01 cal/g C and a Conductivity of 3 w/m C, that would ALSO equal a thermal Differential of 3.01. under your system you're saying that these two substances with exactly the same differential would perform the same?

yeah. likely. *chuckle*

look at the thermal differnetial for metal versus liquid.
the higher the number the better.

http://speakeasy.net/~language/images/graph-differentialliquid.gif http://speakeasy.net/~language/images/graph-differentialmetal.gif

thermal differential is the description of the relationship. this relationship can be expressed in many different ways, but this one is ours.

100% Ethanol - 27%
100% Methanol - 42%

this isn't rocket science. higher is better. how do we get this? we are looking at a relationship between the specific heat and the conductivity of a liquid while in steady state heat transfer (not phase change, not solid state, not florida state, not anything else - steady state)

look at the conductivity rates and the specific heat indexes of liquids versus metals. we want a high conductivity and a low specific heat index ideally. we do not want our coolant to store thermal energy- we want it to transfer it as quickly as possible, not hang onto it.

http://speakeasy.net/~language/images/graph-capacity.gif

http://speakeasy.net/~language/images/graph-conductivity.gif

BUT
you cannot have one without the other. all materials have these characteristics - Specific Heat and Conductivity. you CANNOT look at one set of characteristics without looking at the other at the same time.

for example:
what if you had a metal that had an incredibly great Heat Conductivity rating of 628 (w/m C) but had a horrible Specific Heat index of 10 (cal/gram C)?

you'd have a metal that transfered heat only slightly better than water.

or look at it this way...

if you had an olympic gold medalist track star with two recently broken arms versus a perfectly healthy highschool track runner, which one would finish a 2 mile run first?

okay, don't hurt yourself, i'll answer it for you - the highschool kid. whats the point of this parable? you have to look at the whole picture in order to make accurate predictions, not just one set of stats or another.

Since conductivity is much more important, it should be weighted more heavily.

wrong again. you keep getting lost in the details. it's not one set of characteristics over the other, it's the relationship between these two characteristics that is important.

silver is certainly not twice as good as copper, actually i doubt it’s even better at all.

do i really have to address this statement? yes sappo - silver really IS better than copper for heat transfer - ask anyone on earth with even the most rudimentary knowledge of heat transfer.

A second mistake is that you should include density into the equation. Those thermal capacity figures only factor grams. When you fill up a reservor grams are variable. The thing that is constant is the VOLUME. So you'll need to multiply the capacity by the density. I dont think it would make much of a difference because 1) heat capacity doenst really make a difference anyway, and 2), i think all the liquids that were examined differ only slightly in density.

it's possible that this is a better technique. so go ahead. do it. the numbers are all there. knock it up. lets see it.

edit: Density plays no part in steady-state heat transfer. you're wrong again sappo.

if you're going to do it, do it by volume.

sorry to rain on your parade, but you are wrong wrong wrong. Can i get a witness up in here?!?! *dead silence*

you don't need a witness, you need a decent science teacher.

YA BABY! I HAVE EXERCIZED THE DEMONS!!!

i'm revising my statement. you don't need a witness, you need a therapist and drugs. lots of drugs.

[sappo]

Ok about the Methanol thing, I was wrong. I looked at that first viscosity chart, and made the mistake of thinking that the right on the X-axis meant more. Next time I'll be careful to make sure that right actually does mean more, just like it has on every graph ive ever looked at.

listen, i didn't make this stuff up. is it possible i'm wrong? sure. but i'm not. thermal differential isn't just something i whipped up on ths spot to make me feel good and you feel bad. if you don't believe me, go and talk to my friend Dave Smith over at the AMDmb forums (aka Myv65 ---myv65@yahoo.com---) who wrote THIS article that Hoot had stickied right below this post right here.

so what if you had a fluid that had a Specific heat of 3 cal/g C (3 times more than water) and a Conductivity of 0.01 w/m C? (approximately 60 times worse than water)

according to your system of ADDING these numbers together, this mystery fluid would have a Thermal Differential of 3.01 versus that of water which is at 1.6 under your system - according to your system, this mystery fluid could be predicted to outperform water by 3 TIMES as much, even though it conducts thermal energy 60 TIMES worse than water.

not a chance.


Good greif, you're still sticking to your guns. Its posted on a forum, it must be right, you say. It's best not to stick to your guns when there's holes in your "findings".

Well, if you had actually read all of what i had said, and not broken it up, it would have made alot more sense. Look, if it was WEIGHTED, it wouldnt add up to be 3.01. Since conductivity is much more desirable than than heat capacity, try multiplying the conductivity by 100 times. Water would be .6X100+1=61 the "mystery fluid" would be .01x100+3=4, making water 15 times better than the mystery fluid. Now that 100 figure is just to show you that a weighted addition would work. I'm not saying that conductivity really is 100x better. This explains the inconsistancies in your differential chart perfectly. You're saying that copper conducts heat over 7000 times better than water. Uh, na. I dont think so. I cant believe you're being so dogmatic when you admit yourself that gold isnt better than silver, but your dumb chart says it is. Give it up. Let it go.....

what if you had a metal that had an incredibly great Heat Conductivity rating of 628 (w/m C) but had a horrible Specific Heat index of 10 (cal/gram C)?

DUDE! Specific heat is GOOD, not bad. Your example was just retarted. Imagine you are the cpu. you put out heat. Now imagine there are two bath tubs you can hop into (tub A and tub B). They both have the same thermal conductivity, and they are both 10C. However, tub A has a heat capacity of one half of tub B. Which one is going to cool you down more? B, it takes twice the energy to heat it up. Tub B will cool you more. No if's, and's, or but's about it. You're are wrong, very very wrong.

If you're still too thick headed to be convinced, imagine if the heat capacity was infinite. Would that be good for cooling or bad... HMMMM.. tough one

do i really have to address this statement? yes brainiac - silver really IS better than copper for heat transfer - yes brainiac it's almost twice as good. ask anyone on earth with even the most rudimentary knowledge of heat transfer.

Na man, high heat capacity is good. If silver was twice as good, it would be used for heatsinks. Think im crazy? The amount of silver it would take to make a decent sized heatsink is about $60. With the cost of machining it would be well under $100. People spent nearly that much when copper heatsinks first came out. Think they wouldnt spend that much for somethign twice as good??? Then why has no one made one?

it's possible that this is a better technique. so go ahead. do it. the numbers are all there. knock it up. lets see it.

Translation: You were right and I was wrong. Im so embarrassed that i spent all that time organizing graphs when they were wrong from the get go.

BTW. isnt it customary for the guy that made the mistake to fix it? Im doing you a favor here. Fix it yourself chump.

Once again, i was wrong on viscosity. I'm man enough to admit it, but your whole differential chart is so fouled up that I'm embarrassed for you.

[sappo]

Found something so good it deserves a new post altogether. I just found out that zinc has a higher "thermal differential" than Aluminum. We've reached a major conundrum here. Do we say that aluminum is a better material for heatsinks and say we are wrong, or do we say that zinc must therefore be a better material and still stick to our guns??

[r0ckstarbob]

Originally posted by sappo
Ok about the Methanol thing, I was wrong. I looked at that first viscosity chart, and made the mistake of thinking that the right on the X-axis meant more. Next time I'll be careful to make sure that right actually does mean more, just like it has on every graph ive ever looked at.

translation: hi, i'm sappo and i wouldn't know a motherboard from a frozen pizza, but like.. could i cool it with 7up or Pepsi maybe? and then we could make rootbeer floats out of them when we're done. that like... would be sooo cool.

Good greif, you're still sticking to your guns. Its posted on a forum, it must be right, you say. It's best not to stick to your guns when there's holes in your "findings".

i just collected and collated data. don't think i ever stated that my techniques were perfect or without fault but i think it's obvious you have some issues. Dave was among those people who helped me interpret the numbers and understand what i was looking at. he's a mechanical engineer who does cooling systems for paper mills among other things. i'm not subscribing to dogma by pointing to something posted on a forum, i'm pointing to a reliable source of information that has been proven time and time again.

Well, if you had actually read all of what i had said, and not broken it up, it would have made alot more sense. Look, if it was WEIGHTED, it wouldnt add up to be 3.01. Since conductivity is much more desirable than than heat capacity, try multiplying the conductivity by 100 times.

hunh?

Water would be .6X100+1=61 the "mystery fluid" would be .01x100+3=4, making water 15 times better than the mystery fluid. Now that 100 figure is just to show you that a weighted addition would work. I'm not saying that it really conductivity is 100x better. This explains the inconsistancies in your differential chart perfectly. You're saying that copper conducts heat over
7000 times better than water. Uh, na. I dont think so.

why would we do this again? just to make your screwed up numbers work? so what you're saying is that we should just arbitrarily start adding numbers until they make us feel good and your system works, huh? this is beginning to sound a whole lot like "gee if we'd scored more points we would have won the game". we'll call this wishful thinking. or maybe fairytale mathematics by sappo.

and noooo sappo... i'm saying that copper conducts energy 700% better than water, not 7000 times. i AM saying however that copper (as a system) transfers energy 7104% better than water on an even playing field, during a steady-state heat transfer scenario. this means that if there were a way to cycle copper through a hose without generating friction heat and cycle it the same way we cycle water through a water block, the copper would out perform water by 7000 percent. alternately, if you could somehow make a heatsink out of nothing but water and bolt it to the CPU somehow, again copper would outperform water by 7000 percent.

but we can't. not in reality. maybe in Sappo's fantasy world it's possible. but not here. not now. sorry charrie. dream on.

the truth of the matter is that the model i created was designed from the word go to examine liquids and coolants, not metals. i extended the model to include metals for the same reason i included things like hydrogen peroxide, as a control and to put things into perspective. thats why we call it a comparison. it compares. this model was never designed to look take a hard indepth look at metals (though in theory it can), as metals can only ever be used in a static steady state heat transfer system. and in a static steady state heat transfer model, Specific Heat has NO impact on heat transfer - it only measures how hot or how cold your heat sink is while it's doing it's job.

note: the russians used to use molten metal as their coolant in nuclear reactors because nothing transfers heat as well... but that only worked because the coolant was at 3500 C and the operating temperature of the reactors needed to remain somewhere around 5000 C or something ridiculous like that. maybe you could look into something like that in Sappo land...

I cant believe you're being so dogmatic when you admit yourself that gold isnt better than silver, but your dumb chart says it is. Give it up. Let it go.....

okay, this isn't dogma, this is basic physics. welcome to the wonderful world of chemistry. i'm sorry it makes you uncomfortable. does reality often do that to you?

this is pathetic. i was giving you a hyperbolic scenerio to illustrate the inconsistancies with your premise. weighted mathmatics hunh?

riiight.

DUDE! Specific heat is GOOD, not bad. Your example was just retarted.

d00d, specific heat is NOT necessarily good. only in your hypothetical fairyland world is it good or evil.

and in a steady-state heat transfer scenario, specific heat by itself HAS NO IMPACT WHATSOEVER on static steady state heat transfer.

and i can only assume that you actually meant RETARDED and not retarted.

Imagine you are the cpu. you put out heat. Now imagine there are two bath tubs you can hop into (tub A and tub B). They both have the same thermal conductivity, and they are both 10C. However, tub A has a heat capacity of one half of tub B. Which one is going to cool you down more? B, it takes twice the energy to heat it up. Tub B will cool you more. No if's, and's, or but's about it. You're are wrong, very very wrong.

If you're still too thick headed to be convinced, imagine if the heat capacity was infinite. Would that be good for cooling or bad... HMMMM.. tough one

if heat capacity were infinite. yes it would be good. but it's not. your example is flawed like the rest of your arguements. Specific heat is finite and the fact of the matter is that we're dealing with steady-state heat transfer and using a replenishable medium in which to transfer energy, not an imaginary endless well in which to pour heat into... your example is not a model for steady state heat transfer, just a one time cool down job. not what we're doing.

but then again, thats if we get tied up in the details. but we're not. we have to deal in whole systems. and we're back to where we started, back to the thermal differential because we have to deal with the conductivity of an item too.

If silver was twice as good, it would be used for heatsinks.

silver IS used for heat sinks you moron.

Think im crazy? The amount of silver it would take to make a decent sized heatsink is about $60.

silver shot, unmilled and unforged, not in ingots, wire or sheet retails in bulk for around $6.70 an ounce from Alpha Supply in Seattle Washington. thats not counting design, development, production, promotion, packaging, and transportation costs just to bring it to market. $60 dollars might be a little conservative, don't you think?

With the cost of machining it would be well under $100. People spent nearly that much when copper heatsinks first came out. Think they wouldnt spend that much for somethign twice as good??? Then why has no one made one?

well i guess if i lived in lala land and could make numbers up like you obviously do that would probably be a viable option. completely silver heat sinks tend to be a little cost prohibitive manufacturers tend to use silver in parts or in pieces instead... or they use it in an alloy more often than not.

but yes, they do make silver heat sinks. they also make this stuff called arctic silver - maybe you've heard of it? hm, why don't they make arctic copper i wonder? hmmm?

they sure as hell don't use diamond or mercury for computer cooling.


Translation: You were right and I was wrong. Im so embarrassed that i spent all that time organizing graphs when they were wrong from the get go.

BTW. isnt it customary for the guy that made the mistake to fix it? Im doing you a favor here. Fix it yourself chump.


step up or step off. theres nothing wrong with this data or the techniques used to compile and compare it. if you can do better, pAH-LEEEEASE do it. otherwise shut your whiney pie hole.

Once again, i was wrong on viscosity. I'm man enough to admit it, but your whole differential chart is so fouled that I'm embarrassed for you.

thus far you've been wrong on viscosity, silver (manufacture costs AND thermal properties), mercury, density, specific heat in a steady-state heat transfer model, the thermal differential, and almost every other arguement you've proposed so far, you fail to grasp the intricacys of steady-state heat transfer and you've managed to kick and scream the whole way down. just climb off the horse Eric. please. you talk to me about embarassing? watching you do this is just plain painful.

but seriously, thats really touching. you're embarrassed for me? wow, i'll loose some sleep over it now... an stuff. i prolly won't ever be the same. oh please sappo, won't you ever forgive me?

i got your chump right here.

[r0ckstarbob]

read it sappo:

http://www.amdmb.com/article-display.php?ArticleID=105&PageID=3

if you continue to have questions, email him.

this is a waste of time. when you're done being in la la land, come back and talk. i'm really interested in everything you have to say.

[sappo]

no prob man. hey, i'll even field all the questions and comments others might so you wont be "wasting time" anymore in this thread. you'll never have to come back again.

[r0ckstarbob]

well, finally. 17,000 hits after the fact, after having this data and information published on a dozen websites, after having these findings consistantly backed up and correlated with facts, data, and other knowledgable people on the subject time and time again... 6 months after the fact, FINALLY Sappo's come to the forefront with the REAL truth complete with weighted mathematics, obscure inaccurate hypothetic speculations, and the drive to cool his computer with Belvedere. Thank you in advance for all the help i'm sure you're about to bring us ignorants here at overclockers.com. take a bow sappo. you're number one.




ya know it's too bad you're such a dense jerk, i think you prolly have quite a bit to offer the forums here... almost as much as they have to offer you.

*shrugs*

i'm not wrong. and you won't go through the work and don't have the data to prove me wrong because it's not there. if you can do it better, then shut up and do it.

oricinally posted by myv65 at the AMDmb Forums



Truth: Density has no direct relationship with steady-state heat transfer.


http://www.amdmb.com/article-display.php?ArticleID=105&PageID=4

[sappo]

straight outta overclockers.com (http://www.overclockers.com/tips670/)

The conclusion is simple: If we compare two heatsinks identical in shape and dimensions made of copper and aluminum, the one made of copper is going to perform better since it will have both total thermal conductivity and total capacity higher than the other one.

Of course, I dont blindly accept anything that is published online. Common sense backs me up here, and please note the usage of the word *SIMPLE* cause it's not that difficult.

If you have 3 heatsinks identically dimensioned, one copper, one silver, and one aluminum. Assuming all are the same temp, the copper heatsink will be able to hold the most heat. The silver heatsink will only hold 69% of the heat and the Aluminum will only be able to hold 62%. This is what negates silver's minimal heat transfer ratio which is only about 5%.

'nuff said.

if you had an olympic gold medalist track star with two recently broken arms versus a perfectly healthy highschool track runner, which one would finish a 2 mile run first?

okay, don't hurt yourself, i'll answer it for you - the highschool kid. whats the point of this parable? you have to look at the whole picture in order to make accurate predictions, not just one set of stats or another.

Had to comment on this. Any boxing fans out there? The most amazing fight I ever saw was when Roy Jones Jr. whooped up on what was supposedly "a" #1 contendor at the time. Unfortunately the fight went the distance. After the fight, they interviewed Jones and he said he had broken his (right?) arm about two weeks before the fight in training. I was floored, but the replays confirmed it. He only did use one arm. Did anyone else see it?? Make no mistake, Jones is the best pound for pound fighter (or shall i say he has the best specific volume index... actually that was terrible) in the world, maybe ever.

Edit: Here's the link. i got a couple details wrong, but the story speaks for itself http://www.tribuneindia.com/2000/20000119/sports.htm#7

[r0ckstarbob]

Originally posted by sappo
straight outta overclockers.com (http://www.overclockers.com/tips670/)

Of course, I dont blindly accept anything that is published online. Common sense backs me up here, and please note the usage of the word *SIMPLE* cause it's not that difficult.

If you have 3 heatsinks identically dimensioned, one copper, one silver, and one aluminum. Assuming all are the same temp, the copper heatsink will be able to hold the most heat. The silver heatsink will only hold 69% of the heat and the Aluminum will only be able to hold 62%. This is what negates silver's minimal heat transfer ratio which is only about 5%.

'nuff said.

no, you're still wrong.

normally i'd be nice about all this but you came in with both guns blazing and now you're going to eat crow.

copper heatsink will outperform an aluminum heatsink, and a silver heatsink will outperform a copper one. this is not rocket science. and it's not because of it's specific heat index, it's because of it's Thermal Differential - in specific it's conductivity rating.

you are not thinking steady-state heat transfer.

here, have some laws of physics, thermodynamics, and overclocking.

THE SPECIFIC HEAT INDEX OF A MATERIAL HAS NO IMPACT UPON STEADY STATE HEAT TRANSFER.

SILVER WILL ALWAYS OUTPERFORM COPPER

Had to comment on this. Any boxing fans out there? The most amazing fight I ever saw was when Roy Jones Jr. whooped up on what was supposedly "a" #1 contendor at the time. Unfortunately the fight went the distance. After the fight, they interviewed Jones and he said he had broken his (right?) arm about two weeks before the fight in training. I was floored, but the replays confirmed it. He only did use one arm. Did anyone else see it?? Make no mistake, Jones is the best pound for pound fighter (or shall i say he has the best specific volume index... actually that was terrible) in the world, maybe ever.

Edit: Here's the link. i got a couple details wrong, but the story speaks for itself http://www.tribuneindia.com/2000/20000119/sports.htm#7

Translation : i couldn't hit water if i fell out of a boat and since i dont' know anything about computer cooling either, lets change the subject to something i kinda know stuff about - how about boxing?

[r0ckstarbob]

Fact 1: Aluminum has a higher specific heat and lower density than Copper. Specific heat is a measure of how densely a material can store thermal energy. If you add thermal energy to a specific mass of material, it will increase in temperature.

http://www.amdmb.com/images/heattransfer/energystored.gif

The specific heat of aluminum is 903 joules/kg*K at 300K while copper is only 385. The density of aluminum is 2702 kg/m^3 at 300K while copper’s is 8933. The product of specific heat and density determines how much energy may be stored in a given volume. For a given volume of material, copper will store more energy at a given temperature change than aluminum.

False Perception: Since aluminum stores less energy per volume, it must be more efficient at getting rid of heat.

Truth: During steady-state operation, there is no net energy storage in the heat sink or fins/pins; hence, specific heat plays no part in steady-state performance.

Fact 2: Aluminum has lower density than Copper. Volume for volume, aluminum is much lighter than copper.

False Perception: Weight acts as a “sink�Efor heat. Since copper is more dense, it absorbs heat well from the die. Since aluminum is light, it gets rid of heat more effectively than copper.

Truth: Density has no direct relationship with steady-state heat transfer.

Fact 3: A small volume of aluminum will cool more quickly than an equal volume of copper once the heat source is gone. This is due to the same reason as fact #1, namely there is less energy stored per unit volume is aluminum than copper. This is, however, a transient condition. Heat transfer from a computer is a steady-state condition where the temperature of the heat sink remains relatively constant. The specific heat of a material partially determines how a material responds to transient conditions but has no effect at all on steady-state operation.

False Perception: Since aluminum cools more quickly once a heat source is removed, it must be more efficient at convection.

Truth: The heat source driving energy into the heat sink remains in effect until you turn off your computer. If you have aluminum pins or fins, congratulations, they will cool off more quickly than copper ones after you shutdown your PC.

The only properties belonging to the solid that affect convection are geometry and surface temperature. The fluid stream has no knowledge of what lies beneath the surface of the material. If an aluminum and copper item have the same precise geometry including microscopic surface details and they have the same temperature then they will have precisely the same convection.

If you are still unconvinced, consider this little thought exercise. Imagine a magic heat sink pin. This magic pin has an adjustable conduction coefficient that allows you to dial the conduction coefficient between a range of zero and infinity. Heat enters the magic pin through its connection to the heat sink. Heat leaves the magic pin through air convection.

When the pin’s conduction coefficient is very near zero, heat has a tough time transferring down the length of the pin. The end near the heat sink gets very hot, while the opposite end remains cool. Convection can only occur with a temperature differential, thus only occurs near the hot end. Most of the pin does no useful work.

When the pin’s conduction coefficient is near infinity, there is little resistance to conduction. The pin will attain a nearly uniform temperature over its entire length and convection will occur over its entire length.

Now let us go back to the aluminum versus copper debate. Copper’s higher conductivity means is that a thinner copper fin can transmit as much heat as a thicker aluminum fin. However, on a weight-basis, aluminum can conduct more heat than copper. If weight was no object, copper holds the edge. When weight is a limitation, aluminum has the advantage. Conductivity multiplied by density is a "weighted" measure of a material’s conduction efficiency. It is this "weighted" efficiency that leads to the use of aluminum in the fins/pins of many heat sinks. It is certainly not because "aluminum gets rid of heat better than copper".

http://www.amdmb.com/images/heattransfer/graph.gif



and would you look at that, silver outperforms copper. jeez. who would of thunk it? and wait@! thats not MY chart now is it???

hmmm

and just to clarify here, according to my professors, there are two types of steady state heat transfer, static and dynamic. mostly what daves writing about here is static steady state for the purposes of simplicity. when you're cycling something like liquid, thats dynamic steady-state. heatsinks are static steady-state. when you're dealing with dynamic steady-state heat transfer, such as a coolant, the specific heat makes a slightly different impact upon things, which is why with coolants we defer to the relationship between the specific heat and the conductivity ie the thermal differential.

this was pulled directly from the AMDmb website. author Dave Smith aka myv65. you should go read it.
http://www.amdmb.com/article-display.php?ArticleID=105

[sappo]

I dont even know why I bother, but

(QUESTION 1) if "specific heat plays no part in steady-state performance" why is it a huge factor in your thermal differential???

Supposedly in your thermal differential, silver boosts from about a 5% performance advantage (just factoring conductivity) over copper to a 75% advantage. Then there's that HUGE nagging problem of gold whooping up on all. Oh ya, and then there's the comical problem of zinc being better than aluminum.

Using your thermal differential where gold is the best (we'll call it "r0ckstarbob's gold standard"), zinc has 11% of the performance of r0ckstarbob's gold standard, aluminum has 10%, silver has 77%, and copper has 44%.

(QUESTION 2) Would you hold it that zinc would make a better heatsink than aluminum??

(QUESTION 3) Would you still hold to it that a silver heatsink is nearly twice as good as a copper one?


specific heat plays no part in steady-state performance.

That quote was the nail in your coffin. It showed that specific heat was unimportant. All this time you have been saying that it is every bit as important as thermal conductivity.

=======
Start Edit
=======
Also note we know that CPU's aren't perfectly steady state. The temps change quite a bit during full load and idle. If silver only has a 6% thermal conductivity rating over copper in steady state transfer, that margin would shrink even more with a CPU because copper is able to hold 50% more heat than silver.

Truthfully, I'm not sure if in steady state heat transfers, that specific heat is a factor. I have always advocated that it makes little or no difference. And if it DID, specific heat was a GOOD thing not a bad thing. YOUR "CALCULATIONS" HAVE BEEN SHOWING THAT SPECIFIC HEAT IS A BAD THING. After much searching online I have found two credible articles, but they are in disagreement: the one at amdmb.com and the one at overclockers.com (http://www.overclockers.com/tips670/).. The one at overclockers says heat capacity is good:
Why is the thermal capacity so important? In a few words, if the heatsink base and fins are too thin and light, they will not be able to absorb enough heat without a substantial rise in temperature, making the CPU run too hot. It is very likely that, in case of heatsink comparisons, the heaviest one with the largest total surface is going to be an overall winner if they are all made of the same material.

That explanation is a really good one, but I'm not convinced it is all that important. ***Also, if you read the article, take note that they do factor in density***

The one at amdmb.com says it makes no difference during steady state operation (but as I have already said, CPU's aren't completely steady state). Just so you know that amdmb.com isn't infallible they said this: The newly designed Z4 Aqua combines a gear-star mazed silver plated copper alloy core for maximum heat absorption with an aluminium top for maximum heat dissipation.
located here (http://www.amdmb.com/article-display.php?ArticleID=189)

Aluminum doenst give off heat better than other metals.

Rockstarbob, either way, you are wrong. You have said specific heat makes as big of difference as conductivity, AND that the more specific heat something has, the WORSE it is.
=========
End edit
=========

Im tired of of saying I'm right. There's no point. I'm more worried about your sanity. And dont bother writing back if if you are not gonna answer those questions, you've backed yourself into a corner and you have ZERO credibility before you can answer them.

I've been watching your posts go from technical, to non technical, to absurd, to not even containing your thoughts but random articles you've found online. I think that's funny (and sad). So dont get on my case for posting a couple sentences on Roy Jones.

[r0ckstarbob]

as long as CPU's are putting our heat (ie are receiving power and are functioning), they are a steady-state heat source. it's only when you turn your computer off does it quit being a steady-state heat source.

during dynamic steady state heat transfer, Specific Heat by itself plays a small part of the whole process to transfer energy, taking a back seat to Conductivity. but Specific Heat cannot be ignored (even though it does not play as direct a part as conductivity) when dealing with coolants due to the nature of the techniques involved. it is the relationship between the two characteristics that will play a crutial factor in coolant performance predictions, not one aspect of it or another. you want to take one little piece of the pie and say "here is the answer" and i am saying that you cannot approach complex systems in the manner you seem so want to do, and expect reliable results. this shortcut searching appears to be a recurring problem with you if your comments on this and other threads are anything to guage by. and on the forums, they are. sorry sappo. there are no shortcuts in overclocking. i'm not trying to be mean to you. thats just the way it works.

my calculations and conclusions show what the numbers show. nothing more, nothing less. i don't particulary care what works better, i just wanted to know what worked the best, and be able to prove it. i'm not making anything up. the only thing that is the remote bit wishy washy is my personal theory why gold doesn't stack up the way we know it does, and i qualified that at the beginning. my conclusions are based upon the facts that i have been able to correlate... and the facts are that: materials that transfer heat the best, tend to have a low Specific Heat and a high Conductivity rating in relationship to one another. look at the numbers eric. go get them from somewhere else if you need to, the numbers won't be any different.

i don't know if zinc would be better at heat transfer, i've never looked into it. i would guess that it would probably look okay initially if you looked at nothing but the thermal characteristics and tried to run a comparison.

but again, that is typical of your approach, isn't it. to want to find the shortcut, take one piece of the puzzle and cry eureka! zinc may indeed look better if you take all those characteristics out of context and didn't look at the plethora of other reasons why it would be BAD to consider using Zinc. the same way you tried to do with mercury.

i do know that aluminum isn't all that great for heat transfer, but it's cheap and easy to manipulate and it works okay.

and yes, i would hold that silver is by far and away a vastly better material to use for heat transfer and i have the chemistry and physics to back me up. credibility? i've got it fallin out my ears. am i perfect? nope. so far though, all you've done is try to shoot holes in my findings without so much as an alternate or improved model to supplement it. unless you REALLY want to consider weighted mathmatics as a possible recourse (for your sake i hope you don't). you've come up with no scientific or mathmatical premise to back your arguements up, no data. just a truck load of complaints, poorly formed arguements based on those complaints, and the tenacity to hold on and let this horse kick you to death. my model of the thermal differential isn't the only one to be had and there are many ways to express this relationship. if you have a better way i invite you to demonstrate it here. (and i invited you to earlier as i recall). i don't mind heated discussion but leave the half-formed, immature, poorly thought out, and creditless arguements at home. weighted mathematics. indeed. bring some facts. improve the knowledge pool.

and before you are willing to discredit an EXTREMELY good article written by someone with more credibility and thermodynamic knowledge than you'll ever see in your lifetime by pointing out an article written by someone else on a different topic on the same website, i'd take a long hard look at your own position and premise for a statement like that and quickly reevaluate.

it takes nothing to try and poke holes in others arguements. anyone can walk by and take potshots with or without any kind of knowledge or background (as you've clearly demonstrated).

try to establish a document for the good of the community that can withstand the rigors of public scrutiny one of these days and then come and talk to me about credibility and corners and the like.

my findings can and have withstood your arguements. you've been able to provide nothing in the way of an accurate alternate model in which to work from, no scientific or mathematical basis in which to measure it, no laws of thermodynamics to back your baseless hypothesis' with. in fact you've been able to convey little more than a generalized feeling of righteousness and angst that appears to be based on little else than your personal desire for things to be different, or if nothing else, for you to be right.

okay, you can be right. well done sappo. you're right. woo hoo.

the rest of us will have to console ourselves with being accurate.

[sappo]

as long as CPU's are putting our heat (ie are receiving power and are functioning), they are a steady-state heat source. it's only when you turn your computer off does it quit being a steady-state heat source.


Perhaps you are not familiar with the differences in temp between idol and full load...

during dynamic steady state heat transfer, Specific Heat by itself plays a small part of the whole process to transfer energy, taking a back seat to Conductivity.

You got an equation for this "back steat" theory? what a load.

but Specific Heat cannot be ignored (even though it does not play as direct a part as conductivity) when dealing with coolants due to the nature of the techniques involved. it is the relationship between the two characteristics that will play a crutial factor in coolant performance predictions, not one aspect of it or another.

Cannot be ignored..? relationship? this is sounding like phychology.. Surly not physics. you dont have logic or math to back you up.

The line of thinking that the easiest explanation to a problem is probably the right one went RIGHT out the window there!

you want to take one little piece of the pie and say "here is the answer" and i am saying that you cannot approach complex systems in the manner you seem so want to do, and expect reliable results. this shortcut searching appears to be a recurring problem with you if your comments on this and other threads are anything to guage by.

Ok, so after the highly ambiguous language above, we start talking about pieces of pies. Excuse me, but dont go around proving someone else is calculating things wrong by pretending to be a physchologist. Can you tell me what type of "relationship" they have? Direct? linear? Negative?

Maybe some numbers to back you up there? Or perhaps its a father/son relationship?

and on the forums, they are. sorry sappo. there are no shortcuts in overclocking. i'm not trying to be mean to you. thats just the way it works.

my calculations and conclusions show what the numbers show. nothing more, nothing less. i don't particulary care what works better, i just wanted to know what worked the best, and be able to prove it.

Good cliche's. Unfortunately, they dont mean a thing.

i'm not making anything up. the only thing that is the remote bit wishy washy is my personal theory why gold doesn't stack up the way we know it does, and i qualified that at the beginning.

Oh, so as long as you say from the BEGINNING that gold makes no sense, everything is ok. Maybe, like in Lord of the Rings, Gold is always cool, even if you put it in the fire. Maybe gold still has some of those properties left over from Middle Earth.

But hey, if you say it's off BEFORE you draw any conclusions, you should be OK. I forgot that was one of the steps in the scientific method.

my conclusions are based upon the facts that i have been able to correlate...

No, mine are. Thats why were're having this disagreement. See, if I beleived that, we wouldnt be having this disagreement. Duh.

and the facts are that: materials that transfer heat the best, tend to have a low Specific Heat and a high Conductivity rating in relationship to one another. look at the numbers eric. go get them from somewhere else if you need to, the numbers won't be any different.

Ah yes, the old trend/fact. Unfortunately for you, thats not right. Zinc, platinum, and Tungsten are a few sore thumb standouts. You wanna see a coorelation between one thing and another, look at electrical conductivity vs. thermal conductivity in metals.

But who cares? BUT THAT'S COMPLETELY OFF THE SUBJECT. YOU MADE NO POINT WHEN YOU SAID THAT. HOWEVER, IM ASSUMING IT WAS IMPORTANT BECAUSE IT WAS UNDERLINED. SO WHAT'S YOUR POINT????

i don't know if zinc would be better at heat transfer, i've never looked into it. i would guess that it would probably look okay initially if you looked at nothing but the thermal characteristics and tried to run a comparison.

Translation: I cant make a inference on anything. It must be spoon-fed to me by some guy with an engineering degree. Although I suppose if anyone makes a statement that disagrees with my conclusions I could infer that they are wrong.

COMEON MAN! WHICH IS IT?? YEA OR NAY?

but again, as typical of your approach, isn't it. thats if you take those characteristics out of context and didn't look at the plethora of other reasons why it would be BAD to consider using it. the same way you tried to do with mercury.

Ok, mercury is liquid. Thats a pretty big factor. But what factors seperate zinc and aluminum?

i do know that aluminum isn't all that great for heat transfer, but it's cheap and easy to manipulate and it works okay.

That's probably the dumbest comment you have made thus far. I believe Aluminum ranks only behind certain arrangements of carbon, silver, gold, and copper. How in the world does that make alunimum "[not] all that great for heat transfer." You're joking right?

and yes brainiac, i would hold that silver is by far and away a vastly better material to use for heat transfer and i have the chemistry and physics to back me up.

BAHAHA. YOU'RE disagreeing with the chart from amdmb.com. It shows that silver only holds a slight advantage over copper in thermal conductivity. 6% to be more exact. So it gets all the rest from the back seat/relationship/pie thingey? Oh wait! but thats not important in steady state heat transfer right?

Oh my..

credibility? i've got it fallin out my ears. am i perfect? nope.

Hmm.. there seems to be some dissention somewhere in that statement.

so far though, all you've done is try to shoot holes in my findings without so much as an alternate or improved model to supplement it.

Ok, thats a fair statement. Here's what I've been trying to say: Specific heat makes little or no difference. And IF it DOES make adifference it is a GOOD thing.

In your thermal differential you divide conductivity by heat capacity. If heat capacity is reduced to one half, your thermal differnetial (which is hogwash anyway) doubles. You are saying that they are EQUALLY significant and that capacity is BAD. That is absolutely wrong!

Piece of the pie??? Hello, you are bringing in two factors. Remember when we learned fractions to call those halves?

Both are equally important in your "equation" (conductivity/capacity). THATS WHAT YOUR THERMAL DIFFERENTIAL EQUATION IS SAYING. DONT YOU SEE IT??

If not, here's what the "equation" means. If thermal capacity is reduced to one half, the *cough* thermal differential doubles. Where in the world does the whole "back seat" "piece of the pie" thing come into this equation? It doesn't..

Why am i argueing FOR your equation? It doesnt make sense anyway. The really funny thing is that your equation is wrong AND you dont even know what it means.. BAHAHAHA!!

And you say you have math, physics, and chemistry on your side? ROTFLMAO...

unless you REALLY want to consider weighted mathmatics as a possible recourse (for your sake i hope you don't). you've come up with no scientific or mathmatical premise to back your arguements up, no data.

funny how YOU of all people should be accusing me of that.

just a truck load of complaints, poorly formed arguements based on those complaints, and the tenacity to hold on and let this horse kick you to death. my model of the thermal differential isn't the only one to be had

funny how i cant find those "resources" online. Thermal differential is the difference in temp between the heatsink and the air. It is a MEASUREMENT. Not some stupid number to tell you how efficient a meterial would be for a heatsink.

and there are many ways to express this relationship.

Oh. there's the cop out for not having any resources to back it up.... Other people call it other things.. Goodness sakes.

if you have a better way i invite you to demonstrate it here. (and i invited you to earlier as i recall). i don't mind heated discussion but leave the half-formed, immature, poorly thought out, and creditless arguements at home. weighted mathematics. indeed. bring some facts. improve the knowledge pool.

Translation: Anything you do is wrong. But spend alot of time doing it, because I'm embarrassed im the only one that spent so much time on it.

and before you are willing to discredit an EXTREMELY good article written by someone with more credibility and thermodynamic knowledge than you'll ever see in your lifetime by pointing out an article written by someone else on a different topic on the same website, i'd take a long hard look at your own position and premise for a statement like that and quickly reevaluate.

No no, YOU were disagreeing with his statements. (see above).

it takes nothing to try and poke holes in others arguements. anyone can walk by and take potshots with or without any kind of knowledge or background (as you've clearly demonstrated).

Yes, and you would know. Iv'e been trying to show you your mistakes by examples, each time, it opens up a new can of worms and a cage of red herrings.

Try this one on for size, bucko. In your charts You said that aluminum conducts 155 watts to silver's 417. Thats absolutely wrong. Luckily, I dont have to explain anything. It's all in the math. Aluminum's relative conductivity is about 56% of silver's (you can get that figure from a # of sites). So aluminum would conduct somewhere in the 233 range. Look it up!

Aluminum was wrong all this time, har har har. Now I know what you are probably thinking. "Thats why zinc was so high!" Recrunch the numbers. Zinc is still better. Explain that one, poptart. Where are all your 16,000 viewers now?

try to establish a document for the good of the community that can withstand the rigors of public scrutiny one of these days and then come and talk to me about credibility and corners and the like.

Good one... I advise you to do the same. And another thing: just because someone disagrees, does not make them wrong, so be open-minded.

my findings can and have withstood your arguements. you've been able to provide nothing in the way of an accurate alternate model in which to work from, no scientific or mathematical basis in which to measure it, no laws of thermodynamics to back your baseless hypothesis' with. in fact you've been able to convey little more than a generalized feeling of righteousness and angst that appears to be based on little else than your personal desire for things to be different, or if nothing else, for you to be right.

I think this statement can best be sumarized by what roy jones jr's opponent said: "I think I hurt him to the body," said Telesco. "I think I did enough to win." It's alot easier saying youre right when you cant PROVE your right.

Personal attacks now, eh? Declaring yourself the victor, eh?

That is really funny because after responding to your ENTIRE post, I have responded to virtually NO technically related material. How can this be?

okay, you can be right. well done sappo. you're right. woo hoo.

Make up your mind.

the rest of us will have to console ourselves with being accurate.

Speak for yourself.

[r0ckstarbob]

you're right about aluminum being a little higher. my bad.

as long as you're consistantly putting energy (heat) into something, you are engaging in a steady state heat transfer model. idle or load have no relavance except to determine how much energy is being delt with. in both cases you're still perpetually putting energy into a substance. thats why its called steady-state heat transfer. there is always heat going into it whether in idle or at load.

ya know, i've just spent the last 9 months in school studying thermodynamics where i've had an opportunity to tweak and verify my results, have recently had my data and conclusions reviewed by professors here at the University of Washington (and have been accepted into the mechanical engineering program based in large part upon the weight of my work in this arena), am continuing my degree in Industrial Design at the Seattle Institute of Art, and my findings are available to the public for scrutiny. and in each instance, these findings have passed muster. it's not perfect and i never claimed it would be, but it's damn close - and a damn sight closer than anything you've ever done.



this thread has seen over 16,000 hits, it's data archived, and has been published multiple times on multiple sites.




calm down




you're ranting like a lunatic and i'm tired of having to explain the basic fundamentals of thermodynamics and heat transfer to you while you continue to try to forward arguements that, while may not entirely be without merit in some cases, are self defeating in your zealousness to be entirely right when you are not.




bye bye sap ol buddy. come back when you get a grip.

[safemode]

since we have lunatics debating i figured i'd have to say something.


A heatsink's function is to move heat from point a to point b and to make point B as big as possible. Because air sucks at cooling. Air has a sucky specic heat and has a sucky heat conductivity.


Air can only take in a certain amount of energy at any given time (constant as per temp) and a high specifc heat material made heatsink is going to be at the exact same temp as the low specific heat heatsink (assuming it's not lower than the substance it's transferring heat into).

This is because that middle-man substance (heatsink) cannot transfer it's heat that it absorbs, be it small or large specific heat, until it's temp differential reaches a temperature that's high enough to efficiently transfer it's heat to our ending substance (air even for watercooling guys unless they are plugged into tap and have constant new flow).

Everything in between the source and the end substance only have heat conductivity to care about. High heat conductivity means the temp differential doesn't have to be that high to begin transferring heat efficiently.

So the answer is, no, heatsink material's specific heat doesn't matter for a damn. Air's does because it's what we're dumping heat into and we get rid of that and completely new air comes along. We dont care what the air transfers heat into, it's not our problem.

Everything including air has heat conductivity to care about. We want everything to have a high heat conductivity to make sure we have as low of a temp differential needed to transfer heat as possible.

I dont really see what the big debate is. Your heatsink isn't going to work if it doesn't get hot enough to transfer heat to whatever it's supposed to transfer heat into and if that's not air then that's not gonna work until it get's hot enough to transfer heat. So it doesn't matter if you have a new compound that has the same conductivity as copper but can absorb 10W/g or only what copper can absorb before it increases 1 C, it's still going to end up being the same temp because air is still the same and it will only begin absorbing heat when you reach the necessary temp (which would be the same if all environmental conditions were the same). The exact same thing is true for water cooling and any other kind of cooling that eventually relies on air to absorb heat. Air sucks, water cooling is just an efficient way to increase the surface area the heat is spread across (and spread it evenly) so more air comes into contact with it at any given moment at least with inline systems).

It's _all_ about conductivity...the higher the lower the temp differential has to be and thus the cooler the cpu can be.

Is there really an argument over this? or did someone lose their medication?

[r0ckstarbob]

basically thats it. this whole arguement has degraded into some really obscure semantics that 99% of watercoolers/overclockers couldn't give a damn about... myself included. what it boils down to is you want high conductivity in your liquid because adjusting pump speed is far easier to do than trying to mess with radiator efficiency.

thanks for the lunacy check safemode. :)

[myv65]

I can only shake my head when folks get this worked up over what really amounts to a trivial matter.

To safemode,

Thanks for injecting a little sanity back into this thread. It was sorely needed.

To sappo,

You mentioned boxing earlier. I'd kindly ask both you and Scott to step to your respective corners for as long as it takes to cool off. You've both said some stuff in error even though both have been correct almost exclusively. Biggest problem I've got with your statements is you flit back and forth between discussing heat sinks and fluids while talking about the relative benefits of conductivity, specific heat, etc. They are different animals and have different factors that dominate their performance.

To Scott (r0ckstarbob),

Darn near everything you wrote is technically correct, but you put too much importance on "thermal differential".

To all,

No pun intended, but what it really boils down to is the basic equation defining convection, namely that q = h * A * delta-T. "q" is heat transfer, "A" is surface area, and "delta-T" is mean temperature difference between the liquid and surface. "h" is the ill-understood convection coefficient. Both "h" and "delta-T" must be applied over each teeny-tiny area as they vary according to the localized temperatures. Call 'em continuous functions if you're a mathematical sort.

"h" can not be analytically determined. In a nutshell, it's a function of how efficiently heat is being transferred between the fluid and the surface. More specifically, it's a function of localized velocity, surface shape, velocity profile (dependent on many factors including geometry and viscosity), and temperature-dependent fluid properties (conduction coefficient, viscosity, specific heat, etc.). Of all this stuff, we have little control over any of it.

We get to choose a block, pump, (insert rest of your system here), fluid, CPU, and to a degree the CPU power. For a given setup, we kind of live with what we have. Of all these things that go into determining convection, viscosity rules. Here is why.

Viscosity is a large determinant of boundary layer thickness. For a given fluid velocity and surface geometry the boundary layer thickness correlates to the viscosity. Higher viscosity means a higher boundary layer. Thick boundary layers mean that very little mixing occurs between the fluid "just passing through" and the fluid that's basically stuck to the solid's surface. Thick boundary layers place a premium on a fluid's conductivity and have no place in water cooling.

Low viscosity means low boundary layer thickness. Low boundary layer thickness means less separation between the fluid "just passing through" and the stuff basically stuck to the solid's surface. This reduces the dependence on the fluid's conduction coefficient. This is the first reason why low viscosity is critical.

The second reason is flow rate. Once you choose your system components, the flow rate you'll get depends on the fluid viscosity. Forget about varying pump speed. Most folks run AC pumps that run at a speed synchronous to the line voltage. Yup, there are ways around it, but most won't bother. Second, provided the power input by the pump doesn't become dominant (more than ~1/2 of the CPU power), more flow will always improve the CPU temperature.

High viscosity results in decreased flow rate. Decreased flow means decreased velocity, hence decreased convection coefficient.

This is the double-whammy of high viscosity.

You might as well toss both conduction and specific heat out the window in relation to fluids. With the right viscosity, you can always generate enough flow (with our typical fluids) to overcome low conductivity and/or low specific heat.

In heat sinks, quite the opposite is the case. Obviously viscosity has no bearing on a heat sink. Both conductivity and specific heat do, however.

A brief explanation of "steady-state": Steady-state means "does not vary with time". CPUs do not follow this definition, but it still applies. CPU power will vary with time, but in the worst-case it runs at 100% load all the time. If the cooling system can't handle this, it is not a viable cooling option.

In liquid cooling, some people think it can't be steady-state because the fluid is continually heating up and cooling. Nah, it's a matter of perception. An engineer analyzing the situation would define a "control surface" around the interested area. Say it's the block. The control surface would surround the block, cutting through the inlet and exit. Water crossing the inlet would always be the same temperature in steady-state. Water exiting the block would always be the same (and warmer than inlet) temperature in steady-state. The CPU would put a constant power level into the block.

OK, back to conventional heat sinks. Specific heat is grossly misunderstood by the computing public. All specific heat does is determine how quickly something changes temperature when you leave a steady-state condition. You have high specific heat? Temperatures won't change quickly. Vice versa is also true. You want an analogy?

Think of specific heat as car velocity and heat sink mass as car size. A bigger car can't negotiate a slalom course as quickly as a smaller car. You have more heat sink mass, it won't change temperature as quickly as a low-mass heat sink. You're going really fast? You won't be able to turn as quickly. You have high specific heat? You won't be able to change temperatures as quickly.

And much like cars, how quickly you weave through a slalom doesn't mean squat about how fast you can go in a straight line. This comes down to power and aerodynamics. In heat sinks, this comes down to conductivity.

Well, I've said my peace and hope it helps someone along the way. My thanks if you've managed to read this far without falling asleep.

[r0ckstarbob]

right-O... i'm off.

:burn: :burn: :burn: :burn:

** hops off to happy hour at the Lava Lounge **

[sappo]

first of all to rockstarbob, i think i came on a little strong, and i said some things that i should not have. i'm sorry.. Also, thanks for listening. I didnt think i was getting through.

now to myv65, you have me sold on the whole convection thing.. That makes perfect sense me.

Also the boundry layer is something i have never thought of.... BUT (and far be it from me to start a huge debate).. isnt that the same thing as the surface tension? In which case the boundry layer would not be directly related to the viscosity. Because soap takes away the surface tension even though soap adds viscosity to the water.

Another problem i have with your post on viscosity (and correct me if i'm wrong here) is that virtually every liquid pump you can get (for a reasonable price) pumps water. Therefore, it is designed to pump liquid that is about as viscus as water. If the liquid is too viscus, it would obviously be hard on the pump, BUT I also dont think it would be good for the pump if the liquid had an extremely low viscosity either.

Example: A car's RPM's. You dont want the engine to be putting out too many RPM's (like a low-viscosity liquid) because it will be inefficient. You also dont want a car's RPM's to be too slow (as it would be with a highly viscus liquid).

[safemode]

the only reason you dont want higher rpms with the same power going into getting those rpms as the engine was designed to is because of thermal breakdown. High rpms cause more friction than the engine is designed to handle and more friction causes extreme heat and lubrication breaks down and you get a chunk of useless metal in your car. This is true of pumps and fans and everything else with moving parts. This is why you don't want extremely low viscous liquids..

[safemode]

Also i dont see the logic in this constant heat term. It doesn't make sense with itself. You're not putting a constant magnitude of heat into it and it causes much more confusion that it's useful.

Make up some other term to describe heat transfer material and a term to describe heat dumping material.

Heat dumping material would be air in almost all cases i can think of. This is a material that for all purposes is infinite in quantity and never re-used.

Heat transfer material is a reused and usually fixed amount of material that is used to move heat from the heat source to the heat dumping material and thus out of your environment.

Have fun with that.

[myv65]

Viscosity and surface tension are not the same thing. In fact, as Scott said in his write-up there are actually two measures of viscosity. They differ only in that one is divided by the density of the fluid.

Boundary layer thickness is pretty much a function of geometry, velocity, and viscosity. I'll quote a brief passage from my fluids book "Introduction to Fluid Mechanics" by Robert Fox and Alan McDonald.


In the boundary layer both viscous and inertia forces are important. Consequently, it is not surprising that the Reynolds number (which represents the ratio of inertia to viscous forces) is significant in characterizing boundary-layer flows."


Surface tension essentially defines how well a fluid sticks to itself. It's viscosity that determines how easy it is to pump.

What's really going on in the boundary layer is shear. The fluid at the surface does not move. The fluid "just passing through" moves with relatively high velocity. The transition between zero and the average velocity is the boundary layer. As a cheesy test, you can drag a stick slowly through some 50 weight oil that has dust, sparkles, whatever floating on top. You'll see movement in the dust well away from the stick. Do the same thing with water and you won't see as much motion. Just remember to go slow or you'll screw up the test.

As with engines, there are pumps that rely on the viscosity of the fluid getting pumped for things like seal lubrication. In the extreme cooling conditions that Scott is after, viscosity will always be higher than water at room temperature. Viscosity that is too low is not generally a concern for us.

[sappo]

Thats sounding alot like cohesion. Isnt surface tension a small film on the liquid and cohesion what makes the liquid hold itself togather??

[myv65]

Originally posted by sappo
Thats sounding alot like cohesion. Isnt surface tension a small film on the liquid and cohesion what makes the liquid hold itself togather??

That's what I get for writing late at night. ;)

I should have said that surface tension is how well a fluid sticks to other stuff (adhesion), rather than itself (cohesion).

Anyway, fluids with widely varying viscosity have remarkably similar surface tension. In SI units, it's measured in mN/m, and most liquids fall in the range of 20-40 at 20°C. Water, though with lower viscosity than most, has higher surface tension. It comes in around 73 mN/m at 20°C. This data is all from the same text I referenced previously and pertains to contact of the liquid against air.

For anyone wanting more information on the topic, the text I referenced is a good introductory book on fluids. I'm not sure what revision they're up to now as I had the class, uh, a few years ago. One really nice thing is they provide reference lists to a lot of other texts as appropriate, particularly to offer a greater discussion of a specific topic.

[riprock]

Just an FYI. I watched this thread back late last year to determine what best to use in my new water cooling system:

XP1800+ @ 2000+ (1.6Ghz)
Danger Den Maze 2
Eheim pump
87' Chevette Radiator w/ 130CFM & homemade shroud
Homemade Resevoir
Silicone Tubing

I've been using windshield washer fluid (that the manufacturer in Tulsa told me was 70water/30methanol) for almost one year.

Under full load:
Room air temp 25c
Case air temp 26c
direct die thermal probe temp 33c

My system runs 24/7. When I'm not actually using it, it runs distributed.net. There's no scum in the lines or resevoir. No leaks and the pump is still quiet and working fine.

[Molybdym]

My god, this is the best data out there. All this information. . .all the numbers. . .AHHH[insert pop sound]. You, you wonderful overclockers you. We owe you a thanks.

[r0ckstarbob]

hey guys, just a heads up

theres been a rumor around that people are having a hard time pumping methanol actualy BECAUSE of it's lower viscosity. someone mentioned that it was a pump issue - in that a possible work around solution would be to NOT use a centrifigual pump like 90% of us use... something i hadn't even considered.

any truth to that do you think? are there others having a hard time pumping methanol due to the fundemental nature of a centrifugal pump being what it is? i've not had any problems but on the other hand i'm not using a centrifugal pump and haven't personally run into the problem...

thoughts on this would certainly be welcome.

[grover]

rockstarbob: I agree completely at your conclusions and that plain old water *should* be better than antifreeze, but in my own experience I actually found the reverse to be true. When I replaced my water system with 50/50 petsafe antifreeze (propylene glycol), pretty much the WORST thing I could do by your numbers, my CPU temperatures instantly decreased 1°C, indication that propylene glycol is cooling my system better than water and not 5-6° worse as ideal calculations predict. Any idea why this is true? At the very least it indicates there are variables that haven't been considered here.

Do you know of any experimental data showing the trends for a number of systems with different coolents? I'm particularly interested in water wetter- everything I've heard about it automotive-wise seems to indicate it's a waste of money.

[r0ckstarbob]

i dunno, theres lots of reasons. in the scheme of things, 1C doesn't really seem that much of an improvement. not to discount anything, but you can get plus/minus a couple of degrees just by adjusting flow rates and 'tweaking' your own specific system into set if that makes any sense. if i had to hypothosize (or guess) i guess i'd say that perhaps the antifreeze brought the flow rate down a bit more which in your case might have actually been better for your system? it's been proven that each watercooling system has a "sweet spot", know what i mean? maybe you got closer to the sweetspot. i dunno. so i guess one option is to shrug it off and say "fuggit, it works so why mess wid it?" which i'd prolly end up doing :). the other option i guess i'd suggest straight off the bat would perhaps be to try to go back to 100% water and play with different flow rates for a bit and see if you can't get better results and find your sweet spot. just a guess. other than that i have no idea.

RSB

welcome to the forums

[grover]

Since then, I replaced the pump (couldnt' fit a GF4 in my case with my old resevoir, heh. Figured I might as well upgrade the pump while I'm at it!) and temps have since dropped another 2°C. So, couldn't be hitting the sweet spot from reduced flow causing the improved performance.

[r0ckstarbob]

well, i dunno then. there are innumerable factors to consider to these things - whole systems thinking is critical when trying to troubleshoot watercooling setups if only because there are so many variables. guess if it were me and i got better results with antifreeze and i knew for a fact that antifreeze was worse for my system than pure water, i suppose i'd take that as a red flag pointing to evidence that there was more performance to be squeezed out of my box in some manner, something that i was overlooking somehow or something that could use tweaking.

again, without knowing more about your system it's hard to say off hand. also again though, if you're happy with your performance, then i say chuck it. what is theory in comparison with real world results?

peaz

[r0ckstarbob]

Originally posted by riprock
Just an FYI. I watched this thread back late last year to determine what best to use in my new water cooling system:

XP1800+ @ 2000+ (1.6Ghz)
Danger Den Maze 2
Eheim pump
87' Chevette Radiator w/ 130CFM & homemade shroud
Homemade Resevoir
Silicone Tubing

I've been using windshield washer fluid (that the manufacturer in Tulsa told me was 70water/30methanol) for almost one year.

Under full load:
Room air temp 25c
Case air temp 26c
direct die thermal probe temp 33c

My system runs 24/7. When I'm not actually using it, it runs distributed.net. There's no scum in the lines or resevoir. No leaks and the pump is still quiet and working fine.


niiiice temps btw

[Rottys-R-Us]

Originally posted by r0ckstarbob
what it boils down to is .
:)

Nice work.

I like the what it "BOILS" down to, nice punn :beer:

[dafatguy]

OK Im new here but I read most of this i was lurkin 4 a while lol but the cryin about the methanol is crazy dont drink it youll be ok no baths wit it either also murcury is not safe its fumes linger and there are strick procedures in lab settings too clean it u couldent use it in a chilled sytem anyway

just my 2 bits

by the way excellent thread

[Ri0_6667]

I'm in school right now and I could ask my chemistry teacher, im sure he has lots of info on it. Also its very readily available here so its time to do some experimenting ;)

[apomak88]

thats all good but has anyone thought of using oil instead of water? i think it would be a good solution but i haven't tried it yet. what do you think?:)

[infinitwisdom]

i have spent some considerable time reading this information on coolants and their thermal properties and viscosity. have any of you considered the use of amonia? for many years it has successfully been used in commercial freezers, usually room sized ones. the only reason it is not used in home applications is it's toxicity to humans should the system spring a leak. but in our application we are not looking to use pure amonia, as i am sure it would affect a change in viscosity one way or the other. however a good ratio of water to amonia should be considered here, you have many people who are well qualified enough to determine whether it's use is practical or not. i am not a chemist, but do have some experience in refrigeration, auto refrigeration to be exact. i am a disabled auto technitian. but in my years of studies of various substances and their properties, ammonia is a real contender you have not considered. it works better than freon did, and is not nearly as harmful to the ecosystem. why don't you guys kick this idea around for a bit.

thanks, and i hope this idea helps, or maybe becomes a winner, wisdom.

[I.M.O.G.]

Originally posted by apomak88
thats all good but has anyone thought of using oil instead of water? i think it would be a good solution but i haven't tried it yet. what do you think?:)

oil has been considered. viscosity is a problem. there is a member of another forum who has submerged his entire rig in mineral oil and circulates it into a 45 gallon drum buried in his yard which also serves as a heat exchanger. geothermal cooling. completely silent. he did not modify anything on his motherboard, heatsinks and fans are still in place and the fans rotate very slowly. put his hdd's in ziploc bags and submerged them too. not great temps but you have to respect the courage to be different. :)

[apomak88]

You are right but you can put oil with low viscosity such as sunflower oil.What do you think?

[I.M.O.G.]

same problem still, did you read the start of the thread? what is motivating you to consider oil?

[r0ckstarbob]

oil tends to respond very very poorly to temp drops. it may not become solid, but it'll sludge and stay sludge till the cows come home. it's straight up viscosity-hell all the way. and although there are many different types of oils, i've never found any that would even come close to being competitive as far as thermal properties go. typically you only see oil used as a coolant in industrial applications. big rigs and the like.

ammonia. er, from a distance and at a quick first look that sounds okay but as you look into it it's actually really not. besides the fact that it eats thru almost everything, and is one of the more toxic elements on earth, in order to use it like you're suggesting requires a LOT of special expensive equipment. usually dealing with ammonia so A.) it works and B.) it doesn't sterilize the earth in a several block radius - requires an entirely new HVAC certification type which tends to be a couple of years long and several thousand dollars i'm told. pumping ammonia through our systems is kinda like trying to pump freon, ya know? it kinda sounds good, but it only works if used in a very special way with very special equipment. i'm afraid my poor little rio pump just wouldn't make the cut. you'd need equipment like a compressor and evacuator tubes and a regulator and so on. i hope that makes sense. sorry to shoot anyone down. nice to see this has got people thinking and stretching their minds a bit. asta.

[Redwolf]

Someone needs to try Orange Oil.
http://www.floridachemical.com

Its a cheaper alternative to the Dupont Floranate product.

[rogerdugans]

Bump. :)

Thread resurrection time.