Would it be better to have a high thermal conductive material between the "hot" of the peltier gen and the heat source, or between the peltier "cold" side and the heatsink? Which in theory would yield the highest output and efficiency? Thanks!
Both. The efficiency is dependent on the temperature difference between the hot and cold sides and how efficiently you can move the heat from the hot to the cold side.
No. Do not use shims at all. Use thermal paste.
The paste itself will do the job. Adding shims is only adding additional resistance to heat flow.
Copper has a higher thermal resistance than nothing (no shims).OK, I thought that the copper, which has a higher thermal value than aluminum might actually help...
Heatsink is pretty big.I'm not sure what your goals are but instead of trying to upgrade thermal conductivity,you should look into adding thermal mass.
Beastly chunks of heatsink will act as buffers against any sudden changes in temp,and that will reduce changing current needs.
I've got a T.E.C unit from a refrigerator,I'll up some pics later so you can get a idea of the heatsink size ratios for a constant on application.
Use the analogy of electrical resistance. Anything you put in the path of current flow will add resistance. If you use one layer of copper shims, you now have two layers of paste plus one layer of copper. One layer of paste is still the lowest thermal resistance.
Depends on what you are doing. Adding thermal mass doesn't quite cut it. You need to increase heat flow. I built a T.E. cooler using cold water to remove the heat.
Yes, max op temp is 620F (they are high temp units) for the hot side. So with an aluminum base, I wouldn't get more heat transfer by sanwiching a copper CPU shim between the alum base and unit since copper conducts higher temps than alum? I understand that adding too much material could cause a "resistance" but I was thinking that the shims, which are used on CPU's for heat transfer between the chip and the heatsink would be plausible... thanks.The hot side moves much more energy than the cold side, maybe a few times more. So that's where you need the best thermal conduction.
600'F ABOVE ambient temp sounds very high! Have you checked the max ratings of the peltier device?
Copper has a higher thermal conductivity, and therefore is superior to aluminum in processor cooling.
Copper is better at conducting heat than aluminum, but aluminum is able to radiate the heat into the air better than copper because of its lower density.
You are dealing with two separate issues.
The first problem is getting the heat to the heat sink. Any additional interface between the heat source and the sink is going to reduce heat transfer. Hence shims are a bad idea.
The second problem is getting the heat away from the heat sink. This is where thermal mass and conduction/convection currents play a crucial role. Increased water or air circulation is the most effective.
My professor used to say "You can't push a rope!"
by Duane Benson
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