How can an Aluminum Radiator be better than Copper??
 

I just don't get it...in my world, making RF semiconductors, we would die to use Copper as its thermal conductivity is 400+ degrees Celcius per meter-Kelvin compared to Aluminum at 230+. Copper just radiates heat SOOO much better. Even at twice the size, I can't see how those aftermarket radiators are better, even with all the extra fins. I was thinking about an upgrade, but started to use my logic and you know where that can get you :)

Yeah, I know its lighter, but is it BETTER???

http://www.webelements.com/webelemen...t/Cu/heat.html

http://www.webelements.com/webelemen...t/Al/heat.html

my guesses would be:
aluminum can be cast and recycled easier
may prevent corrosion better

My guess is that it could be the corrosive factor

Copper is better at taking heat away from the liquid, but it tends to keep it instead of giving the heat away to the air.

Alu is faster at giving heat away than Copper.

From what I have read, what you are saying is completely true. However, the rad has more then just one surface for heat exchange. The tubes are not the primary heat exchanger, and here is the issue, traditional copper brass rad's have somewhat smaller tubes in lengh cross section, because if one extrudes oval tubes in copper and the ratio of major dia to minor dia is great, the pressure inside the tubes tries to expand them round and the fins need to contact the tubes with as much contact area so that the fins can grab the heat and release it to the airstream. Aluminum is not as flexible and therefore can be manufactured with tubes with a greater major:minor axis relationship.. That allows the fins to touch lots of area, and exchange lots of heat.

Now, while reviwing this, I was just thinking about evans coolant, and it's use of an atmospheric pressure cooling system. I was thinking one COULD make a copper rad with these long major/minor axis fins, because the internal pressure issue would be resolved. Now one could have an aluminum eliptical tube design rad, but made in copper with copper's superior heat transfer.

I have copper 2ply and 3 ply on my web page, made by Essential. www.jt-imports.com
Jason

Thanks for the discussion. I hadn't realized the mechanical aspects (thermal expansion coefficients). I'll bet someone has a nice ANSYS or TAS thermal model which would show what size/configurations are equivalent for each element.

There is also the issue of the oil cooler, A/C and transmission cooler (if you have one) all competing for the same cool air.

What is Evans coolant??