Heat out of small packages

[Owenator]

I read this article in the December 2001 Issue of Mechanical Engineering Magazine: http://www.memagazine.org/backissues/dec01/features/heatout/heatout.html

It is and interesting read. Basically it is a passive water cooled system. The water is heated to a boil in a waterblock and then it circulates through the radiator an is cooled. The system is under a vaccum like a heat pipe. It says that they got an 85W chip to run at 57C load which I know is hot but it is an interesting idea.

O

 

[Malakai]

heh, silent cooling. interesting
-Malakai

 

[Owenator]

On closer inspection of the pic it lools like there might be a case fan on the radiator it is hard to tell but there is still no pump. I need to see if they wrote a paper on this.

O

 

[francisamf]

It looks like a giganto heat pipe.

If they had a faster boiling and cooling liquid in it, it would probably work better.

 

[Hoot]

Hard to say whether it is a heat pipe, or a gravity cooled system. Still pretty neat picture.

Hoot

 

[Owenator]

francisamf,

It looks like a giganto heat pipe.

If they had a faster boiling and cooling liquid in it, it would probably work better.

Actually the article says that "The working fluid tested in laboratory experiments was the dielectric coolant PF 5060 made by 3M Co.". The one prototype inthe pic used water because of some other issues.

O

 

[Owenator]

Hard to say whether it is a heat pipe, or a gravity cooled system. Still pretty neat picture.

Hoot

Hoot,

It is a form of heat pipe called a "compact thermosyphon". The artilce is pretty good if the link I put in worked. This is the same design problem overclockers solved ages ago too bad we didn't get a pattent

O

 

[Tiger]

This system is close to but not quite like some relatively new cooling technology they call a Loop Heat Pipe. The LHP has been the subject of a lot of research both by NASA and mainly by the Russians. Their prime interest is in cooling space craft. But the principle is a hybrid of heat pipes and refrigeration. The evaporator has a wick usually made of sintered metal and the coolant is fed from a res. The vapour produced by boiling causes pressure to build in the condenser and a vacuum to form on the res side thereby inducing a push pull effect like a compressor. The big plus is the fact that it starts the moment heat is applied unlike an earlier attempt called capillary heat pipes which required pre-heating. According the stuff I read over the weekend the system is capable of moving the vapour and therefore the heat out over considerable distances and when used with liquid ammonia has achieved temps as low as -100C. According to the articles the current forms are capable of cooling 300W and they are projecting that with some more work in excess of 2000W