making radiators

[redleader]

actually there is some truth to the Al disipating heat rumor. It's all due to the fact that aluminum has a lower specific heat than copper. it takes more energy to heat a mass of copper than an equal sized mass of aluminum. Likewise, aluminum also looses heat quicker. However, in most applications(ie. heatsinks) copper is the better metal for heat disipation.

This is not true. Copper dissipates heat faster because heat dissipation depends on conductivity and NOT specific heat capacity.

Now if you had said temperature in place of heat your statement would have been correct, though irrelevent.

[natopotato]

Originally posted by redleader
This is not true. Copper dissipates heat faster because heat dissipation depends on conductivity and NOT specific heat capacity.

Now if you had said temperature in place of heat your statement would have been correct, though irrelevent.

in convection, yes, conductivity is the more important factor. Hence my saying that in most applications of this type (heatsinks), copper is the better material. I was merely stating facts that i believe lead to the perception that Al dissipates heat better in a heatsink type function.

[MadDogMe]

It's certainly where the myth came from, at least partly, but specific heat is an abstract when it comes to comparing two identical designs, basicly it's saying if ALu were squashed/condensed to the same density[?](size and weight[?]) as Cu it would be better, but seeing's how that's impossible...
I think the other part of the myths origin is that ALu cools down quicker after heatsource has been removed...

[Antimatter]

i think from what everyone is saying is: copper has better heat conductivity for volume. aluminum has better heat conductivity for weight.

this would explain why (small) waterbocks are made from copper and (large) air heat sinks are made from aluminum.

so aluminum would probably be a better material for a radiator if weight is an issue. otherwise, copper.

so anyway, i was thinking of maybe just running a bunch of copper tubing around in front of my fans. maybe i could solder some fins onto the tubes. would be very non-flow restrictive if i used 1/2" tubing.

im not sure if this will cool very well though. seems like it should get rid of some heat. it would be like 4 (7v) 80mm fans. some sort of spiral or something...