Originally Posted by GingerJohn;15344371
Not quite. He is refering the the difference between the air temp going into the rad and the water temp coming out.
Ideally you want this to be 0°C, meaning that you are reducing the water to the ambient temperature. This represents the limit of cooling possible without going for active cooling (TECs, phase change etc).
The higher the air - water difference the less optimized your setup.
I'd prefer it if we stuck to wording like "as close to 0C as possible" rather than the thermodynamically impossible. I'm just that way.
Originally Posted by falconer65;15344549
Digging thru these posts, it would seem the heat is not being dissipated and building up in the reservoir.
It seems the only way to get the reservoir hotter than a few °C over ambient would be for the radiator to not be able to dissipate the heat. I could see this happening by either air flow or water flow. First, I would try checking the fans to see if one has gone bad and then speeding up the fans.
Are you folding 24/7?
As someone who is researching water cooling systems, this is all very informative. It parallels what I know about cooling systems for cars. You can run a 4 cylinder radiator on an 8 cylinder for a 1/4 mile run, but just try to go across town!
Back to computers, I have bought a CPU water block and am saving for the rest. As to what the rest will be, I am working on that!
Don't look at it as heat building up in the reservoir - unless you consider ALL the tubing and contained fluid to be the reservoir.
As for vehicle radiator sizing, your logic is flawed. Driving across town requires very little power.
The reason you can "get away with" a small radiator for short busts of power is simple - the cooling system can absorb that heat regardless of it's ability to dissapate it. Top fuel (4,000hp+) drag cars don't have cooling systems that you would recognize (no radiators, no water / green stuff) (Bonus points if you know where that heat goes).
Regardless of an engine's possible output, it takes the same amount of energy to move a 3000lb car up to 30mph. Unless you have a very inefficient v8 and a very efficient I4, the same radiator and airflow will suffice (within a few percentage points, of course).
Throw that I4 radiator at the v8 engine around a racetrack for a while, and you might see a problem.
What prevents overheating in a car is much more related to making sure that you get good flow to the radiator (which means making sure air doesn't bypass the radiator), and that the cooling fan is functioning properly (cooling fans do most of their work when a car isn't
moving very fast).Edited by u3b3rg33k - 10/17/11 at 6:22pm