Heat Transfer Fins

Take a look at Hydronic heating base board units for an example of heat fin design. There is more to the fin then you see when a unit is taken apart. The design is such that the outer sheet metal housing acts as a Ventura to increase air velocity across the fins as well as a decorative cover. Not sure what your designing cooling unit for but there are many profiles on the market now that can be purchased. Or you can order some of the text books that cover these designs, by doing google search.

Thank you.

http://www.smps.us/thermal.html should get you started. You can ALSO google " thermal conductivity " and " thermal properties of metal " for more info. Keep in mind that PASSIVE cooling is one thing, and ACTIVE cooling ( forced air or water cooled ) is a whole 'nother subject.

Hope that helps.

The best thermal conductor is silver followed by copper and then aluminum.

The more surface area you have the better dissipation you get.

They make heat sinks for CPU's that are 2" square, you could put these on each side.

Don't forget the thermal grease between the heat source and the heat sink.

Without knowing more about the application that's about all I know.

this might help

http://www.aavidthermalloy.com/technical/papers/pdfs/elliptical.pdf

as for materials try aluminum or copper as sugested.Are available and good for heat transfer.

As nikolay says, Aavid is a good reference source. See their range of heatsinks here & you will see the multitude of design options available.

Most heatsinks are aluminium as this is a good compromise between performance & price but it needs to be one of the low alloy aluminiums. Copper is better but is more expensive & can be difficult to machine in thin sections.

If it was my choice I would try to use an off the shelf part as you will get the thermal data to go with it.

Smooth,wavy,louver are few types of fins. Each type has its own heat transfer correlations.Any good heat transfer book will provide full details.

Graphene would work wonders but I kinda doubt it fits your budget.

You have to be careful applying thermal grease, thats almost an art form .

Ron

we had the same problem we made our heat sink and then had to go to production so i turned to anywhere for help then i found these guys in a email

http://www.coolinnovations.com

we got the first unit here and tested it im sold they work it was a 247 package at 400 W of power and it was 110 F yes these work and very good

An Aluminum radiator for a microprocessor will work fine. Use thermal grease in the mount and you should be good to go.

As pointed out, silver and copper are better but too expensive. For best results, the heat sink should be black, as black is the best radiator of heat. The more surface area the better, so look for lots of tiny protrusions on the fins.

Fins should be vertical.

Diamond is even better for conducting heat.

Large fins close together for natural cooling, small fins for forced air cooling, stubs for liquid cooling. surfaces should be slightly rough rather than smooth to induce turbulent air flow.

Black anodising of aluminium is better than powder coating or black paint.

When using thermal compound, wring surfaces together to make sure layer is as thin as possible and to squeeze out entrained air.