I wish I could tell you lol, I’m just stumbling along.
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Same page lol
Needle valve to bleeder hose? Adjust as needed so your prv never actually goes off and just acts as a fail safe? Lol
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Isolate a couple prvs set at different pressures?
I do know though that pressure level and the rate of evacuation in a tank of nitrogen correspond with how low a temp that cylinder will reach by the time its empty. So it makes sense to assume that the faster you can evacuate the pressure thats building due to CO2 being exposed to heat, the more energy is being removed along with that evaporation. Due the the effect of evaporative cooling.
This says a lot
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Says I’m a dip shit, take what I say with a lb of salt.
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Soooo much salt
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I’m not sure I’m caught up on the conversation here but doing this with LN2 is actually easier/safer than with CO2 because the CO2 will form dry ice and block the tube.
Ideally, something like a flooded evaporator (good search term if you like) is ideal because it prevents you from wasting unboiled liquid which still has that handy latent heat. A back pressure regulator is probably best for setting the pressure at which the LN2 or LCO2 boils. Basically, the same way you set the boiling point of your solvent in a rotovap by adjusting the vacuum, you can use positive pressure to choose an adequate boiling point for your cryogen. Of course for LN2 the critical point is your limitation, above that there isn’t really a phase change
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I inject liquid LN2 into the jacket of a counter flow heat exchanger and vent the gas out the other end. I control the flow with an orifice or a metering valve on the discharge end.
I use the Dewar valve to turn it off and on, as most valves will cease to operate at subzero temperatures.
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What about sterling cryogenics? Surely they could have some genius people make a sterling powered cryogenic freezer that powers indefinitely…
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Even those darn dewar tanks stay open sometimes
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You’d need a pretty big sterling engine for any real cooling. Like, room sized probably
ive been having issues getting it whenveer infeel like it now. my dry ice man blames it on the corn indursty bc covid. said that they maybe had to throw away tons of it. and they use corn ethanol to make it up north
I wouldnt mind hearing about this. I am trying to build enough capitol to get away from dry ice and get a -80 chiller. But i have also hear that even the good ones dont keep up with the thermo load.
A USAF operational readiness team with Tac-P’s and Combat controllers can make a 1600ft runway anywhere in the world within 36 hours, Air bridge in 72 hours, and ground unit readiness within 96 hours.
I watched the Japanese erect a 3 story warehouse inside of a week. With our powers combined…
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A seriously unhandy event.
Do I infer it was after lengthy rapid transfer of liquid?
How did you close them off?
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I just kept on working! I think it closed eventually
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Well shit man. They should get started on the hangars for c02 enrichment…
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What kind of heat load are you working with @Dankoholic?
New info within the last few days says dry ice is only used during transport for the phizer vaccine.
of course, they rely on china to supply the freezers now.