Phase change cooling

IceFoundry

Junior Member
Sep 22, 2002
15
0
0
Does anyone here use phase change to cool your rigs? Either direct die or water chiller.. not talking to the people that buy pre-fab systems.. but DIY'ers..

I want to get a good thread going about phase change cooling.. and unfortunatly I don't see much more then air cooling topics under the case and cooling forum..
 

lukatmyshu

Senior member
Aug 22, 2001
483
1
0
This has been on the forefront of my mind for the past few weeks (an after effect of studying Thermodynamics) ... I almost feel like Phase Change cooling itself would not be optimal because I am not sure how to implement it directly on the die. I figure if you're going to go through the trouble of that, you might as well doe what (I hope) my next project is going to be. If I take a hollow cube of aluminum with the bottom removed and attach it to my core of my Chip and the epoxy'ing it all together to make it waterproof. I figured I'd use mineral oil or something ot remove heat ... or I guess I could use water and watch as it converts from a liquid to a gas in the presence of a heatsink, and the it would recondense on a panel cooled by a fan and the cycle would continue. My big concerns (aside from the general impractically of the whole project) would be making it airtight ... when the water converts to steam if the seals around the die aren't completely watertight the gas would escape (causing my chip to fry). Also .... what kind of epoxy exists that can handly those temperatures?
Vijay
 

IceFoundry

Junior Member
Sep 22, 2002
15
0
0
I highly doubt using water would work.. mineral oil surely wouldn't and what would you use to pump the liquid/gas? YOu couldn't use a refrigeration compressor that's for sure.

Your best bet is to make/buy a refrigeration unit.. on-die or a water chiller like the ones I build.. I enjoy water chillers because you can do so much with them.. same equipment as water cooling of course.. and you don't need this loud radiator setup anymore..
 

rgwalt

Diamond Member
Apr 22, 2000
7,393
0
0
The other problem of implementing a phase change cooling system with water is that 1) the phase change occurs at 100C unless you pull a vaccum and 2) the pressure increase would likely break the seal.

As far as home-brew phase change systems go... I would start by looking at a pre-built chiller, like a dorm fridge. You could either strip out the guts yourself, or build a system inside the unit. I'm thinking what you should do is put a big reservoir inside the fridge, and run chilled liquid output and return pipes through the door, as well as the power cord for the pump. You could run the chilled liquid through a water block on your chip, or sandwich a peltier cooler between the chip and the waterblock. While this isn't a direct phase-change system that runs on top of your chip, it is a phase change system.

The problem with cooling much below ambient is condensation. Be careful not to "let the smoke out" of anything.

Ryan

 

IceFoundry

Junior Member
Sep 22, 2002
15
0
0
If you are looking for pre-built water chiller I have one I am looking to sell.. more along the lines of local pick-up though.. be kinda hard to ship it with propane in the system.. Knowing UPS they would drop it offa the truck.. i ain't worried about anything bad happening cuz it won't.. just that I do have to tell them what I am shipping.. so their might be extra charges and it's going to be a 55lb shipping weight.. but it's a beautiful system.. performs as good as it looks.
 

serialb

Diamond Member
Mar 20, 2000
3,107
7
81
Phase change cooling? Who doesn't have one at home? We just call it a refrigerator.

IMHO it's technically possible to mod a dorm size fridge, securely connecting hoses to a water block to fit your die. But I am sure it's not economically feasible as you will have to run the compressor continuously, turning your electric bills to unwanted heat, well, unless you live in Minnesota in winter...
 

IceFoundry

Junior Member
Sep 22, 2002
15
0
0
Um.. if you say so..

That idea wouldn't work.. mini-frige compressors suck... You need a good 1/4HP compressor.. or 1/3 .. or.. 1/2 lol.. Besides.. it puts your bill up a whopping 10 bux to run it all the time heh.. And if you are smart you can turn that heat into advantage.. to heat your room.. like you said.. heh