"John Larkin" wrote in message
...

On Tue, 21 Aug 2012 03:19:55 +0200, "Skybuck Flying"
wrote:



wrote in message ...

On Sun, 19 Aug 2012 01:56:38 -0500, "Tim Williams"
wrote:

Note that heat transfer by volume isn't usually the goal, so much as
minimum temperature is. In a counterflow setup, the hottest part of the
heatsink is cooled by the hottest air. If you flip it around, the hottest
part of the heatsink gets cooled by the coolest air, achieving the highest
heat flux for a given surface area and temperature difference -- more
power density, at some expense to mass flow and pumping loss. You might
avoid this, for example, if you had to use pure nitrogen (or helium, for
that matter) for some process, minimizing the gas flow to keep operating
cost down.

"
Why not use compressed/expanded air for this purpose ? Using a piston
compressor to compress the air to a few bars, the air gets quite hot,
then let it go through a heat exchanger to get rid of most of the heat
and cool the pressurized air closer to ambient temperature.

Let the air expand to normal ambient pressure and the air temperature
is now well below ambient temperature and let it flow through
semiconductor heatsinks to the environment.

To avoid problems with dust and condensation, a closed loop might make
sense, but of course, now the heat exchanger would also have to
dissipate the heat from the semiconductor. However, the heat exchanger
can be remotely located and it can have much higher temperatures than
the semiconductors, getting rid of the heat into the environment would
be easier.
"

I like this idea of a closed air system very much...

"
It's been done, with better working fluids. You have one in your
kitchen.
"

Yeah in case such a special case does not exist, a next best thing might
simply be a mini/tiny refrigator and place the entire pc inside of it...

My fridge actually has small little holes on the back side... so some cables
could go through it...

But it's a scary idea... electronics and moist.... hmm I'll have to look
into this somemore...

For now biggest drawback could be noise of fridge.... or maybe fridge can't
handle the pc heat at all...

Hmm..

Bye,
Skybuck.