Looking for heatsinks

[DiverDude]

Originally Posted by StirCrazy

a heat sink actually works on surface area not mass, the more surface area the more heat transfer.

Yes !

But notice I said THERMAL mass. Think of it like thermal capacitance or heat capacity. In the end though, you are correct -it's about the transfer from one medium to the other. You can actually have a very small and light heat sink but at some point, as the thermal mass decreases, you'll need a fan. Whereas with a more thermally (and to an extent, physically) massive heat sink, you may get away without the fan.

[StirCrazy]

Originally Posted by DiverDude

Yes !

But notice I said THERMAL mass. Think of it like thermal capacitance or heat capacity.

ok you are using different terms than we used in thermodynamics

for instance heat capacity is how much a material will hold, which is what we don't want in this aplication as we want it to transfer it as fast as it can, not hold it.

and thermal mass is realy a measument to the resistance of temp change.. more specificaly the ability to hold heat and release it slowly, which again we don't want.

what we want is a material that has a high thermal conductivity, which means it passes on heat very easily when there is a temp difference.

so we mean the same thing I guess, but your choice of words confused the issue

Steve