Autocascade Design
07.06.06 - 04:51pm
Just thought I’d make a quick update, I have my initial design for my autocascade. Over the next week I will continue to update this design till I feel happy with it. Hopefully I will commence building this system the weekend after next if all the parts get here.
Here is the description of the system that I posted on XS.org.
Starting from the Compressor it will go as follows
1)Test port and a small coil for anti-vibration purposes
2)Air-Refrigerant Condenser
3)Phase Separator, most likely homemade, packed with copper wool to seperate oil
Low-side : Liquid line with sight glass, liquid-line filter/drier, and a test port
High-side : single test port leading into “.031 cap tube, I might put a filter drier here to keep the cap tube from clogging.
4)Heat exchanger, it’ll either be a simple coil or maybe a plate HX if the budget permits it
5)High-side : Liquid-line filter/drier, a sight glass, another test port, and then a high pressure burst valve. Since I would like to avoid venting CO2 and r290 into the environment I will try to find a suitable cylinder to vent into. I suppose I just need enough volume to contain some overflow, just an idea right now.
Low-side : possibly spiral the suction line around the liquid high-side and then proceed to the accumulator
6) Some sort of metering device will be put before the evap, I’m not sure which valve to use, CPEV or TXV. I think I’d like to avoid cap tube as this will be the portion that really needs tuning.
7) High-side: suction line merges into the low-side.
8) Suctoin line leads into liquid accumulator tank to keep from flooding the compressor, then a test port after the accumulator with the possibility of a sight glass.
So far that is the design, I tried to implement enough ports and sight glasses so that I will be able to effectively tune this monster. I’ll keep you guys posted on my results, should be a very exciting build
Pardon me for being totally ignorant, but, what’s an “Autocascade?”
You aren’t ignorant at all, this is definitely not a normal form of refrigeration. In regular refrigeration you have a single gas that gets compressed, and then released into your evaporator and it expands, sucking up a bunch of heat. This simple process repeats itself over and over again.
Autocascades use two gasses. you cool them down to ambient temperatures and one of the will condense. You will then use this liquified gas to supercool your second gas. You do this in the heat exchanger, you chill the second gas and it will condense while the other gas will evaporate from a liquid. Now your supercooled gas is used to hit some really low temperatures, I’m shooting for -100* Celsius.
This entire contraption will be slapped onto my new processor to supercool it and it’ll permit me to hit some very insane overclocks. Some might say overkill, I say fun.
Phew…….I just felt that go way over my head.
Never has MS Paint looked so darn good. =)
Sorry guys, the next couple of posts in regards to phase cooling might be a bit hardcore jargon and what not. I won’t totally focus on phase change, but since it is my current project, expect some of this stuff to pop up. My MS Paint skills rock your world.
Chris,
Autocascading = awesome. Is it really expensive to do? Is that why more computers aren’t cooled like this? or because at these levels it’s not necessary yet? Fill me in, I’m actually quite curious…
Raf
Hi Guys as refrigeration engineer im very impressed with your project.These systems work at -80 realy well but be warned the insulation required to nacchive this is severe the insulated box would need to have sufficent insulation to stop heat being absorbed in the area and also stop the box from sweating,no warm can enter due the humidity freezing instantly and causing frost on any thing storerd in there hpope it helps good luck mate
Jay, glad to see another refrigeration engineer checking out my project. It’ll take a lot of insulation but thankfully I can just pack this thing with foam and not worry about making it TOO transportable. I have been slightly delayed over the last couple of weeks with other projects but this weekend might be the begining of the build.