Has anyone seen any guide on how to calculate heat transfer for rads and waterblocks?

[brwmogazos]

i need to do some basic calculations for heat transfer

on a waterblock for example, or radiators etc etc

while cooling a cpu so that i can calculate an expected temp in order to compare it with the readings take from bios?

in general words i need to do some basic calculations...or find any articles with analysis etc. etc...

thanks in advance :)

[helsyeah]

From what i can remember from my heat transfer class the equations were far from simple, especially in forced convection situations with a heatsink or waterblock. You could simplify the problem down to using a flat plate example where the equations are easier to play with, but for accuracy, im not sure if you will be within 10% of the actual temperature.

I know that a radiator can be analyzed using several different methods for heat-exchangers, but to do this i beleive you need to know the temp for the air on the inlet and outlet of the rad, as well as one of the inlet or outlet temps for the water within the radiator... but again, i dont remember the analysis being particually simple...

Ok, so my point is, i cant think of any simple equations that will give you accurate results, sorry dude.

[chilly1]

I just recieved a packet from Innovative Research,Inc. www.inres.com that claims they have a software that will calculate loads for the electronics industry. I havent looked at it too closley been busy.... might be worth a look..

[blinky]

for radiators and waterblocks, i would think calculating the heat absorbed or dissapated would involve measuring the temp of coolant (water) going into it and the temp coming out, then somehow (im really tired right now) using the specific heat of water u can find out how many watts were absorbed

[OwcA]

For a very basic estimate you can use

P = (S * lambda * deltaT) / d

for every join of two different solid materials where

P - heat current
S - surface area
lambda - specific heat of the material heat is passing through (for example copper for a WB)
deltaT - temperature difference between the cold and hot side of the join.
d - thickness of the material heat is passing through

When working with fluids (especialy when the fluid flow is mostly turbolent) things get much more complicated as geometry (for example the shape of radiator fins) and angles of attack join the party.

[TheDude]

PM saaya, he had a nice tool for that. I can't seem to find it now.