Phase Change Chiller Discussion

[LethalCorpse]

In addition to being a homebrewer, I'm also something of a computer geek - I found this site through the homebrew thread on Overclockers Australia. The sometimes extreme ways in which we cool our CPUs have led to some interesting rumination in the area of chillers. My first (and probably most likely) concept is to create an immersion chiller which uses the same submerged copper coil as current designs, but using coolant and a pump to recirculate it through a large automotive radiator and fan - a larger scale model of computer water/air cooling. I've been thinking about another of the extreme cooling options though, in phase change cooling - modifying a fridge or aircon compressor to cool a block mounted on the surface to be cooled. Such a block could be mounted (with some accounting for curvature, or possibly just panel beating) to the outside surface of the kettle after the boil, and then turned on to very quickly cool it down to pitching temps. The mounting I've mentioned is one potential problem, another is what effects a very small contact area for cooling would have on the fluid dynamics (and chemical processes) within the wort, a third is how such a refridgerative cooling system copes with boiling temperatures, whether you make contact after it's already boiling, or if the die is fixed mounted. These could, to some extent, be mitigated by using a dual loop system, which consists of a watercooling loop as for immersion chilling that goes to a conventional waterblock instead of a radiator, where the block is directly mounted on the phase change system's die. The waterloop includes a large reservoir to act as a buffer for sudden changes in heat load/effort on either side of the loop as well as handling changes in pressure due to temperature by just rising and falling volume.
Will it fly, Orville?

 

[Sammus]

I think it wouldn't be powerful enough to cool even 25L of boiling wort (or more for the double batch guys) all that quickly. Surely the cooling time wouldn't be too different to sticking the kettle into the fridge. (same compressor, fridge is a pretty good insulator so not much cooling of anything but whats inside it...)

 

[LethalCorpse]

I think it wouldn't be powerful enough to cool even 25L of boiling wort (or more for the double batch guys) all that quickly. Surely the cooling time wouldn't be too different to sticking the kettle into the fridge. (same compressor, fridge is a pretty good insulator so not much cooling of anything but whats inside it...)

true, but you're using air to transfer the heat to the compressor, which makes it take much much longer than having a direct interface.