Whats a low drop pressure radiator?

[[PCA]Pheonix]

yeah yeah I know I'm a n0000000b

and Is there a high drop pressure radiator.

[ptcg]

Check this post...

Here (http://forums.overclockers.ws/vb/showthread.php?s=&threadid=43411&highlight=low+pressure+drop)

[[PCA]Pheonix]

Thanks!

[BillA]

try to work through the Radiator article on the front page
it has good info and descriptions

the link cited is junk (simply wrong)

be cool

[ptcg]

Why would you say the link was 'simply wrong'? I thought I had a fairly decent description of what 'low pressure drop' meant... That is what was asked after all...

[mldhab]

"Low pressure drop Radiator" would indicate a radiator that would have a small difference in pressure between the inlet and outlet at a given flow rate. Definately read the article mentioned above. The 'Heater Core' style radiator is what you are after.;)

[BillA]

the "low pressure drop" radiators described as such are generally called stacked (flat) plate due to their manner of construction
they are aluminum oil coolers generally used on the low pressure side (return line) of power steering or automatic transmissions

"low pressure drop" is a relative description which DangerDen points out in their advertising text
"15 times less flow restriction vs standard radiators"

so first we need to look at a "standard radiator"
but on this their advertising text is not so clear
the other choices are the Cube, Super Cube, and heater core ??
are any of these a "standard radiator" ?

or did DangerDen make an unquantified comparison to something not described OR defined ?
(how I do so LOVE advertising copy)

ptcg, they made a BS statement - lower than WHAT ?

now you made an assumption as to what a standard radiator might be, with which I have no difficulty (typical automotive crossflow configuration) but your description of the hydraulics is incorrect.

the radiator testing article (http://www.overclockers.com/articles481/) on page 3 shows both types: E - surplus is a minature automobile type, and I - 4x4 and J - 4x8 are both of DD's "low flow" type.

on page 4 there is a plot of the pressure drop vs. the flow rate for all of the radiators and it can be seen that both types are quite similar.

no 15 times less flow here

perhaps DD meant "standard" to be their continous tube type ?
well, the larger "low flow" has 1/2 the pressure drop (and the smaller 1/4), thats certainally NOT the 1/15th of the advertising copy !

ok, so DD is swilling out BS for the uninformed

and your "technical" rational is incorrect
the pressure drop is a consequence of the sidewall friction (related to the velocity), the length of the flow path, and the changes in direction. For components such as radiators it's best determined experimentally, though certain portions such as the tubes are easily calculated.

be cool

[ptcg]

You don't feel that the size of the flow path contributes to the pressure drop? If you have a 3/8" inlet/outlet and the ends of the radiator are large cavities, with the cooling paths between them, wouldn't this create the pressure drop? I know if you have a small tube running into a reservoir, there is a large pressure drop on exit of the small tube.. Isn't this basically the same thing?

I saw the graphs & agree with what you said, but didn't your graphs more or less show my point? The automotive-type radiators had a higher pressure drop/lower flow rate than the "low pressure drop" ones.

I wasn't trying to get into a huge debate, just trying to 'over-simply' a description of what was meant by 'low pressure drop' and explain it without all the tech jargon.

basically what I meant was that the low pressure drop rads are supposed to give you a more sustained flow rate & pressure than the automotive-types..

I haven't been to DD in quite a while, & I'm not in the market for a radiator so I can't say anything in regards to their choice of wording in advertising. I wasn't taking anything they said into account on my explaination.

[BillA]

just deleted a lengthy post as I am thinking we are using the same words differently

automotive type = E - surplus, is the only one of that type tested
the Black Ice may look the same but it is very different (4 pass) and has very high flow resistance/pressure drop

low pressure drop I took to mean the stacked plate types which are called that - even though they are not particularly so

"basically what I meant was that the low pressure drop rads are supposed to give you a more sustained flow rate & pressure than the automotive-types.. "

I guess I do not understand specifically which radiators you are referring to.

the only "automotive type" tested was tied for 3ed - 4th out of 10 tested
that seems kind of low pressure drop to me

please identify which radiators you are referring to

be cool

[ptcg]

My mistake.... I was looking at the Black Ice when reading the chart thinking that it was a standard auto-type rad.. Now I see that it is quite different...

"basically what I meant was that the low pressure drop rads are supposed to give you a more sustained flow rate & pressure than the automotive-types.. "

The keyword here is 'supposed'...