ok, somebody plz explain to me what heatpipe cooling is...... and if its any good (n00b) is it any good for hd cooling? cheers
Heat pipes work by utilizing the latent heat absorbed when a liquid undergoes a phase change into a gas, and released when the opposite phase change occurs. Essentially, you have a sealed pipe, with a wick structure on the internal surface, to allow it to operate in any orientation. There is a small amount of water in the pipe, and it is at a pressure quite a bit below atmospheric. At lower pressures, water boils at lower temperatures. So you can loewr the pressure to a point where water boils at say 40degC. In such a case, you will have one end connected to the heat source, and the other connected to a series of fins. If the heat source rises above 40 deg, then some of the water boils, requiring latent heat to undergo the transformation. This is absorbed from the heat source, thus cooling it. The vaporised water can now diffuse rapidly along the heat pipe to the fins, where the latent heat is dissipated and the water condenses back to a liquid. The water then travels back to the heat source through the wick structure. It is quite a simple process really, but not very easy to manufacture. It's the kind of thing which requires expensive machinery and is done on a very large scale, and you don't really find shops selling individual heatpipes. Neither does a heatpipe remove the need for fans unless it dissipates the thermal load over a large area of fins. I would imagine that a heat pipe hard drive cooler could work, but it isn't really the kind of thing you make yourself, and to be honest, I don't really see the point, as you are simply moving the point which needs cooling. A low powered fan blowing over the hard drive is sufficient. 8-ball
I thought they tended to use something like Methanol rather than water, as with CH3OH you don't need to get a partial vacuum in the tube to reduce the boiling point to something useful. I could be wrong though. If you want a heatpipe HDD cooler, look around for the Zalman ZM-2HC1. It's the only one I remember seeing around anywhere. Lupine.
You can use just about anything really. It depends on the operating conditions and so on. A lot do use water. 8-ball
most of the shuttle xpcs use a custom heatipe designed for fitting inside the case/mounting on the shuttles.... they keep the processor cool, but they aren't amazing performers as they're designed for use in whats basically a small oven
For those of us who like pictures -> http://www.procooling.com/articles/assets/images/ct-team-hc2.gif and for those of us who like to read -> http://www.procooling.com/articles/html/cooling_technologies_explained3.php *should be the last topic at the bottom of the page...*
I might be building a heat-pipe cooled puter so I would be interested in some info. The main one I 'm looking for is what liquide to use (and no I won't vacum my tubes). Acetone seems pretty evil as it eats plastic from my previous experiences
TetarZ, Heat pipes are not easy to build on a small scale. Whether you want low pressure or not, you still need to pull a vacuum to ensure that you have only the charge liquid inside. Unless you REALLY know what you are doing, I would suggest another route. For example, how do you plan to manufacture the internal WICK structure. It is this kind of thing which is very difficult to manufacture. It can be done without, but only if the fins are higher than the heat source, and it's downhill all the way! It is also VERY hard to get the correct amount of liquid, and to get the correct liquid. 8-ball
