Cooling Helium at Bottom Dollar
Cooling Helium at Bottom Dollar
(OP)
Calling all Cryo-guru's,
I'm designing a rig to test a circulation fan. The system is closed loop with Helium as the fluid at temp 50K and pressure 100-300 psi. The piping is 5/8" od (wall thickness is up to me). How does one cool the Helium without spending more than a few hundred dollars on hardware?
My initial thoughts: Buy 100' of 5/8" od (wall thickness .035) from McMaster for $200 (PN: 5174K37). Drop the whole coil into an Igloo marine cooler. Drill two undersized 5/8" holes in the side near the top and pop the two end of the copper piping though. Drill a small hole in the lid for a pressure relief valve. Open the lid, dump a bunch of LN2 in there and call it a day.
Thoughts Please?
I'm designing a rig to test a circulation fan. The system is closed loop with Helium as the fluid at temp 50K and pressure 100-300 psi. The piping is 5/8" od (wall thickness is up to me). How does one cool the Helium without spending more than a few hundred dollars on hardware?
My initial thoughts: Buy 100' of 5/8" od (wall thickness .035) from McMaster for $200 (PN: 5174K37). Drop the whole coil into an Igloo marine cooler. Drill two undersized 5/8" holes in the side near the top and pop the two end of the copper piping though. Drill a small hole in the lid for a pressure relief valve. Open the lid, dump a bunch of LN2 in there and call it a day.
Thoughts Please?





RE: Cooling Helium at Bottom Dollar
RE: Cooling Helium at Bottom Dollar
I'd suggest getting liquid helium for use as the cooling media.
How big is this fan? How much power and what flow is it producing?
RE: Cooling Helium at Bottom Dollar
If I go with liquid Helium as the cooling media, can I use the same setup as I described in my first post? Or am I getting myself into a $500 cryo thermos.
The purpose is to test the circulating fan performance, overall efficiency, clearances at cryo, vibration and displacement checks, and heat leak. I am circulating Helium gas at the following conditions:
Inlet Pressure 7 [bar]absolute
Pressure Ratio 1.034
Inlet Temperature 50 K (or as close I can get)
Mass Flow Rate about 8 [g/s] , 11 [g/s] corrected
Fan Electrical: 110 VAC 100W, .5 amp (small unit, impeller od is about 1 inch. overall length is about 12 in)
Anyone know if the Helium in this case would react with copper (piping)?
RE: Cooling Helium at Bottom Dollar
Problem would be cost. You'll use a lot of liquid helium which is very expensive, materials would cost even more, and just engineering the test is going to be a significant undertaking. If $500 seems like a lot of money, you can forget trying to cool it like this however. It will be tens of thousands of $ to set up a test like that.
I'd suggest that using LIN should be sufficient. Most of your thermal shrinkage will have already occured. How the fan behaves at 77 K should be very representative of how it behaves at 50 K.
RE: Cooling Helium at Bottom Dollar
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