Which heatsink to get?

[Szech]

If you read my other post here: http://sysopt.earthweb.com/forum/Forum1/HTML/005982.html about my little drink cooler project, then you'll know that I'm using a peltier to do it. Well, I got my paycheck three days ago, and I'm about to prove that a fool and his money are soon parted. I'm getting the peltier from allelectronics, and I'd rather get the heatsink and fans from there as well. I think these three heatsinks are the best that they have (or biggest, rather), but I don't know which one to get. Could you help me pick from:

Door number 1. http://www.allelectronics.com/cgi-local/SoftCart.exe/online-store/scstore/p-HS-65.html?L+scstore+qlyh3409ff125b12+960099494

Door number 2: http://www.allelectronics.com/cgi-local/SoftCart.exe/online-store/scstore/p-HS-47.html?L+scstore+qlyh3409ff125b12+960099494

Door number 3: http://www.allelectronics.com/cgi-local/SoftCart.exe/online-store/scstore/p-HS-57.html?L+scstore+qlyh3409ff125b12+960139626

1 is the smallest, but it is annodized black. 3 is the largest, but it has a funny shape. 2 is bigger than one, is a normal shape, but is not annodized black. Other factors to consider: I have to mount a peltier on one side, and a fan/ fans on the other side. Thanks in advance http://sysopt.earthweb.com/forum/smile.gif

[tonym]

I have just one word for you:


ICE!


Save your money on the Peltier and buy yourself about 20 ice trays! Better still, if you want a REALLY cold drink REALLY fast, splurge and buy yourself a tank of LN2. Just remember to get some safety glasses and thermally-insulated gauntlet golves.

The peltier is going to be frustrating unless you make a thermally-conductive Dewar (a copper cup with a flat to which the Peltier can be mounted and coupled with thermal grease. And you may want to have a cup-inside-of-a-cup structure, with an antifreeze fluid coupling the cold to the drink (remember some fluids expand when cooled and you might get a glass or cup stuck in you cooling machine).

As for the heatsink, the cooler that you want to go, the hotter that the other side of the Peltier will get. It might be a good idea to get a long-finned heatsink and then use an external fan to blow air on it, rather than use an integrated fan H/S.

Tony