Noobish Question

Noobish Question (new to water)

Ok ive just started looking at water cooling. Ive read alot about most of the things. But i dont understand what people mean by the terms

loop
fill/bleed
barbs

and I know how a reservoir work, but how does a T-line work? and could anyone show me how it looks like?

and how does the heater core work differently from the normal standard radiator?

and whats the difference between head flow and pressure... they both sound alike

thanks

ps. im still in the process of learning
lol i keep editing my post cause i seem to forget and then remember about these strange words

Loop=The entire circuit of your water-cooling system, which includes blocks, radiator, tubing and the pump. Look at it like a logical circle, hence "loop."

Fill&bleed=The process of filling your loop with coolant and allowing excess air to escape.

barbs=the metal or nylon hardpoints that extend from your blocks, radiator and pump to allow the easy connection of tubing.

A T-line and a res perform the same basic function. They allow you to fill&bleed your loop. AFAIC, both have pros and cons. There's no real difference between a core and a rad. If you want to save some money (in most cases), and don't mind doing some prep work, get a core.

Flow=How much coolant moves through your loop in a given time-frame

Head pressure (dead head)=How far up a up a vertical length of tube your pump can push coolant without all flow stopping. The more a pump's able to push against resistance the more resistance you can have in the form of blocks, tubing, radiator, etc., while still maintaining flow.

A loop is a common reference to a watercooling system, including components and tubing, generally referring to it in a complete and operating sense.

Filling and bleeding is the practice of introducing water into the system after construction, and working to get all of the air trapped out of the system.

Barbs are the (often) threaded tube connections on the in and out of most components, which we slip our tubing over and secure it to. They come in many shapes, sizes and colors, the most common being nylon white and brass metal barbs.

A t-line in the junction is a means of filling/bleeding when you don't use a res (that does not mean they can't be used together, however). You put a T piece in the loop with the extra fitting pointing upwards with a shorter run of tubing attatched to it. You can funnel coolant into this short tubing run and cycle the pump, thus filling the system.

Heatercores are not drastically different from the purpose-built rads we use for watercooling, but are available from many more sources, and can also be much cheaper. They often look less appealing than rads visually, but perform just as well (perhaps better) and can be cleaned up and painted to look very nice.

Flow is the amount of fluid being moved, such as gallons per hour, and head is the measurement of the pressure behind it. 10' of head means that the pump (ideally) can pump water 10' straight up. Not all pumps are equal in this sense, and higher head is always better, and more important than flow.

Never hesistate to ask a question.

Loop is just a term for the watercooling system. All the components (radiator, pump, waterblocks, etc.) which are connected by tubing. The coolants starts at the pump, goes through all the waterblocks and radiator, T-line/reservoir, then back to the pump. That's a loop because it makes a loop.

Fill means you fill up the "loop" with coolant.

Bleed is purging or bleeding the air out of the system. Ever hear of bleeding the brakes on a car? Same thing, you have to get the air bubbles out.

T-line works about the same as a reservoir. It's a vertical tube usually just before the pump that traps air bubbles and gives you a place to fill the system. Here is a pic I stole from Senator Cache (T-line is the half filled tube on the right).



A car heater core and a radiator especially made for computers work exactly the same way by transferring heat from the water via fins to the air.

loop = your watercooling system and all of the parts which it is comprised of (basically, when watercooling, you're creating a closed loop which water continually circulates through. Think of it like a video which has been looped, it plays the same thing over and over again... well, the water behaves like that video, circulating through the system over and over again)

fill/bleed = filling the system/loop with water and/or bleeding (draining) the water out of the system/loop. The term "bleeding" can also be applied to the removal of air from the loop.

barbs = the 'pointy bits' sticking out of waterblocks/other parts that you fit tubing over (Pictures! here, here, and here on a block)

A T-line functions similarly to a reservoir except that it, imho, is easier to work with (and you don't have to worry about having a leaky reservoir). To give you more of a visual, you're basically inserting a t-fitting (one of these ) immediately before the pump's inlet, you attach an extra section of tubing to the vertical barb on the t-fitting, and then proceed to fill the loop through that section of tubing. Once filling is complete, you cap the top of the tube (generally with a fillport or some other suitable object--with 1/2" ID tubing, I've found that an inserted marble with a zip-tie on either side works great). This section of tubing, once capped, also doubles as a "reservoir" for extra coolant.

A heater core works the same way that a standard watercooling radiator does. Many prefer them because they preform very well when used with shrouds and high CFM fans, plus they incur less pressure drop than many of the commercially available 'watercooling radiators'. They, however, are not the ideal solution for a quiet watercooling system. Oh, yeah... and heatercores are usually damn cheap.

Flow and pressure are two completely different things. If you are familiar with electricity and circuits at all, pressure is analogous to voltage and flow is analogous to current. Flowrate, usually measured in GPH, GPM, L/hour, or L/min, (Gallons Per Minute, Gallons Per Hour, Liters/hour, Liters/minute), is very important for overall watercooling system performance--the higher your flowrate, the better the performance should get. Pressure, on the other hand, doesn't really affect system performance... unless you are referring to the flow restriction (pressure drop) of a particular component and how that will affect a particular pump's ability to sustain an acceptable flowrate. Basically, the higher the pressure drop a component has, the more restrictive it'll be, and it's this restriction which results in lower flowrates. Granted, flowrate isn't the be-all, end-all of performance... You'll get great flow through a Maze4 but, performance wise, a Storm at practically any flowrate will beat it. Clear as mud, right?

...and that took me way too long to type... lol

I'll only add that the problem with heatercores is that they are too thick for the spacing of the fins, and hence too restrictive to air flow for the weak fans we use. This is important because flat tube radiators heat up the air flowing through them almost to the temperature of the coolant. Hence, the limit on how much heat you can transfer is how much air your fan can move through the rad, and a less restrictive rad will shed more heat at a given temperature even if it has less surface area. However, heater cores work well enough, and at $20 the price is right.

For $30, you can get a BIP2 or BIP3 from Directron. These are no longer the kings of the PC watercooling hill, but they are very good rads for the price, especially if you are designing a quiet system.
http://store.yahoo.com/directron/iceii.html
http://store.yahoo.com/directron/icepro3.html

Wow, guys, I really didn't expect so much response. Thanks mates.

Otter said:

I'll only add that the problem with heatercores is that they are too thick for the spacing of the fins, and hence too restrictive to air flow for the weak fans we use. This is important because flat tube radiators heat up the air flowing through them almost to the temperature of the coolant. Hence, the limit on how much heat you can transfer is how much air your fan can move through the rad, and a less restrictive rad will shed more heat at a given temperature even if it has less surface area. However, heater cores work well enough, and at $20 the price is right.

Click to expand...

Yeah I heard, therefore most of them use shrouds to channel the air. So basically, heatercores have thick spacing, and the radiators don't? Heatercore = Flat tube radiator? And is there any performance difference between the two. Ive seen the '86 Chevette and the BIP2, but I can't see them close enough to tell whether they have thick spacing of fins or not.

Petra said:

Flow and pressure are two completely different things. If you are familiar with electricity and circuits at all, pressure is analogous to voltage and flow is analogous to current. Flowrate, usually measured in GPH, GPM, L/hour, or L/min, (Gallons Per Minute, Gallons Per Hour, Liters/hour, Liters/minute), is very important for overall watercooling system performance--the higher your flowrate, the better the performance should get. Pressure, on the other hand, doesn't really affect system performance... unless you are referring to the flow restriction (pressure drop) of a particular component and how that will affect a particular pump's ability to sustain an acceptable flowrate. Basically, the higher the pressure drop a component has, the more restrictive it'll be, and it's this restriction which results in lower flowrates. Granted, flowrate isn't the be-all, end-all of performance... You'll get great flow through a Maze4 but, performance wise, a Storm at practically any flowrate will beat it.

Click to expand...

So flow rate is kind of related to head pressure in a sense that, if head pressure is too low then the flow rate at first maybe fast, but after going through all the tubings and the waterblocks, the flow rate will basically be slower?


And isn't the reservior much easier to handle than that T-Line? Looks abit risky if you're going to do maintainance. And you said reservoirs leak, is this very common? Isn't the reservoir like injection moulded, so its like one whole piece of plastic? Unless you're saying that it leaks from the barb area?


Also, I heard that UV dyes aren't good for your pump, is this true?


Going price shopping today, so like Ill get to check on prices and stuff. Quite excited on this watercooling. And on top of that I don't just want to get the best parts, but understand how it works, and which is best for the best price. Will feel even better when I fix it up myself (nothing better than this feeling)

Rickster said:

So flow rate is kind of related to head pressure in a sense that, if head pressure is too low then the flow rate at first maybe fast, but after going through all the tubings and the waterblocks, the flow rate will basically be slower?

Click to expand...

Well, it is, in a way, related to the max. head rating of your pump but not quite in that manner. Flowrate isn't water speed, it's simply a measure of the amount of water that passes through a given point in your loop in a specific amount of time (hence units like Gallons/minute). The volumetric flowrate through your loop is an unchanging thing so, no matter where you measure, it'll always be the same. Flowrate is related to your pump's max head pressure in that the flowrate through your loop depends on your pump's capabilities at the head pressure incurred by the restrictiveness of the components in your loop.

Example:

Say the overall restriction of your loop is equivalent to about 6' of head... At that head pressure, you'd be looking at getting about 120GPH (2GPM) from an MCP655 (D5).

Making a little more sense now?

no matter where you measure, it'll always be the same.

Click to expand...

just wanted to quote and emphisize this in case he missed it in petras post.

this is important and new people often dont understand this .

there are some advanced concepts where this isnt exactly true but you wont really need to know about that untill you understand the basics of flow vs head and how the DT aka the Delta T works.

then you can move onto laminar and impingement and stagnation and other big words that have special rules .

Rickster said:

Yeah I heard, therefore most of them use shrouds to channel the air.

Click to expand...

That's a good idea with any radiator. A shroud will give you better cooling and less noise than bolting the fans directly to the rad, no matter what the rad is.

So basically, heatercores have thick spacing, and the radiators don't?

Click to expand...

Heater cores are usually about 2" thick compared to 1" for most PC rads. Because the air will be heated almost to the coolant temp after going through the first inch of closely spaced fins, the second inch just reduces the air flow.

Heatercore = Flat tube radiator?

Click to expand...

Yes.

And is there any performance difference between the two.

Click to expand...

A well-designed, flat-tube PC rad will give you somewhat better cooling for the same amount of noise. Heater cores aren't bad, though, and you might notice that some of the people with a truckload of stars after their name use them. Both are better than some of the early round-tube PC rads that were produced before watercooling companies realized they could get custom flat-tube rads from the same people who make them for cars.

If you used the cabin blower from a car, a heatercore would be the perfect rad. It was, after all, designed to work with that type of fan. However, the only way to make one of these things truly silent is to turn it off. If you don't mind fairly loud whooshing noises, though, it's a great setup.

BTW what is o-ring? Could anyone show me a picture with the o-ring on the barb?

Otter - I see. So theres really no difference between the heater core and the PC radiator. Infact, in performance wise the PC radiator should be better because of the spacing you were saying and also it requires less noise. The only real advantage I can see is the price? And why do people like the '86 Chevette? Because it is small? Eppppssss cabin blower!!! Sorry I really don't want that noise.


thorilan - Ive been reading and yes I udnerstand that delta T concept.


Petra - Isn't that quite like what I said. So you're saying that if there wasn't any restrictive components in the loop and you just run the pump you should therefore get flowrates of the same amount everywhere you measure the flowrate. However, the WC rigs that we build have restrictive components so therefore the flowrate will decrease further up the loop assuming that we have a constant head pressure

BTW isn't a restriction of loop 6' of head = about 170GPH.

------------------------------------------------------------------------

Ok today I went shopping for the WC products. I couldn't find them anywhere in Malaysia. Arghh... I hate Malaysia, all they do is sell mediocre products to consumers and consumers don't mind it and pay high prices for it because they never do enough research on what they are buying. And the shop I thought that would sell the waterblocks, pumps etc was closed. But I have high doubts that they sell the DIY WC. The shops that sold WC products(a few of them) only sold kits, and I don't want kits. Im thinking about importing these products, not sure from where though. Pain in the arse. Any recommendations? I hate buying through the net, I feel so unsafe, and if there was a defect I have to send it back to US and probably with postage paid on my side. So my question is that, do you guys know online shops that are in the SE asia region, that have good reputation?

Are there old chevy's rolling around Malaysia that need servicing
Well, that doesn't help the made for PC components but a very capable system can be built with out them.

hahahahaha you seem to know about Malaysia. how's that?

I just have to say that this thread's responses have been extremely positive. It's good to know about the volumetric flowrate is a constant throughout the loop, I wasn't 100% sure of this when a large reservoir was considered. Thanks!

Rickster said:

hahahahaha you seem to know about Malaysia. how's that?

Click to expand...

Im in the US.. but I do pay attention to what's going on out east

Rickster said:

Petra - Isn't that quite like what I said. So you're saying that if there wasn't any restrictive components in the loop and you just run the pump you should therefore get flowrates of the same amount everywhere you measure the flowrate. However, the WC rigs that we build have restrictive components so therefore the flowrate will decrease further up the loop assuming that we have a constant head pressure

Click to expand...

*sigh*

In a loop that's setup and running, the volumetric flowrate through the loop doesn't change. Loop pressure, however, does drop as water passes through each of the components but, again, this doesn't actually affect temperatures. Going back to the electricity analogy, if you put an arbitrary number of resistors in series (say 3 resistors of different resistance values), the circuit will have a set current draw--the node amperage (flow) through the circuit will be the same regardless of where you measure. The node voltage (pressure), however, will decrease as electricity (water) travels through the circuit (cooling loop).

Rickster said:

BTW isn't a restriction of loop 6' of head = about 170GPH.

Click to expand...

Typo, sorry about that... I meant 8' of head. I was aiming for a somewhat more realistic number as the flow through most cooling loops is usually between .5GPM and 2GPM. Even with an Iwaki, it's hard to push over 3GPM.

Petra said:

*sigh*

In a loop that's setup and running, the volumetric flowrate through the loop doesn't change. Loop pressure, however, does drop as water passes through each of the components but, again, this doesn't actually affect temperatures. Going back to the electricity analogy, if you put an arbitrary number of resistors in series (say 3 resistors of different resistance values), the circuit will have a set current draw--the node amperage (flow) through the circuit will be the same regardless of where you measure. The node voltage (pressure), however, will decrease as electricity (water) travels through the circuit (cooling loop).


Typo, sorry about that... I meant 8' of head. I was aiming for a somewhat more realistic number as the flow through most cooling loops is usually between .5GPM and 2GPM. Even with an Iwaki, it's hard to push over 3GPM.

Click to expand...

-Flowrate is constant throughout the loop no matter what (like amp which doesnt change at all in the entire circuit)
-Loop pressure is affected by the amount of restrictive components (like voltage which decreases over the amount of resistant)

this is what i understand from what you're saying

sorry if im just not understanding it

Rickster said:

-Flowrate is constant throughout the loop no matter what (like amp which doesnt change at all in the entire circuit)
-Loop pressure is affected by the amount of restrictive components (like voltage which decreases over the amount of resistant)

Click to expand...

Yes, you've got it. As long as you remember that it's a rough analogy and you can't actually use the equations for electricty for water, you can think of flow as being like current and pressure as being like voltage.

Yay

So the thing I really should be looking out for in the pumps is loop pressure/restrictive pressure?

BTW how do you measure head pressure? Im reading some reviews and this guy is doing testing with some equipment and he says he got approximately 1 foot of head. How can you measure head like this?

Rickster said:

Yay

So the thing I really should be looking out for in the pumps is loop pressure/restrictive pressure?

Click to expand...

Yes, the static pressure head. And if you can find it, the P-Q curve, which shows the relationship between pressure and flow.

To measure the head, attach a long tube to the outlet and run it straight up. Connect a tube from the inlet to a bucket of water. Prime the pump and turn it on. The height above the outlet that the column of water reaches is the head. This value is sometimes reported as feet or meters of water, and sometimes as PSI. You can convert the units with this.
http://online.unitconverterpro.com/unit-conversion/convert-alpha/pressure.html

BTW, when I say a long tube, I mean at least 15 feet. You definitely want to do this outdoors. The DDC has 13 feet of head and if you try this test in a room with an 8 foot ceiling, all you'll do is make a fountain.