Questions tagged [compressed-gases]
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How to calculate evaporator and condenser pressure in a vapour compression refrigeration cycle?
Imagine a basic vapour compression refrigeration cycle.
A compressor which sucks gas from the evaporator and pumps it into the condenser at high pressure. The gas loses heat and becomes liquid in the ...
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What are the boundary condition to simulate flow through vent mast?
Dear all,
I am currently working on modeling compressible flows that occur when hydrogen needs to be evacuated (for purging, in case of fire, etc.).
I am endeavoring to determine the appropriate ...
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Explanation of phases of fridge cycle from power draw (power factor, reactive and active power)
I've got this power draw graph of my fridge during a couple of cycles. The power factor axis is on the left, active and reactive power axis in watts/VAr on the right.
I'd like to understand the phases ...
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What is this hole in some gas related threads
What are those holes for? (Those are for CO2.)
Here are a few examples :
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Why are double-acting reciproating compressors more efficient than single-acting ones?
On many websites, I read that double-acting reciprocating compressors are more efficient than single-acting compressors.
These sources say it's because they complete two compression cycles on each ...
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Can rubber be used as the membrane in a diaphragm compressor with a 1:10 or higher compression ratio?
I've been investing time learning about diaphragm compressors and I can't understand how this particular type of compressor can have a 20:1 compression ratio, and what material could stretch that much ...
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How do I purchase cylinders of Hydrogen (H2) gas for person use?
I'm interested in building small model airships, and I would like to purchase a cylinder of H2 gas to fill the envelopes with as is far cheaper and more effective than helium. I've contacted some ...
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How to calculate the required power to pump out (to vacuum) a container?
Consider I have a cubic container with its volume is 1m cubic as in the simple picture above. It is sealed nicely, it is air proof, no air leaking. I would like to pump out (to vacuum) the container ...
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Can a compressor give the same discharge pressure even if suction pressure varies?
The task is to maintain compressor discharge pressure at 200 bars. The inlet pressure varies with time from 200 bars to 10 bars (emptying a compressed air tank and compressing to transfer it to ...
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Driving an air cylinder with ignited hydrogen/oxygen gas mixture from fuel cell?
Summary:
I need to build a linear actuator that has a very fast actuating speed but fits in a very small space.
My Question/Idea:
Electric gearmotors, c02, and air pressure, are all ideas that come to ...
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How to transfer high pressure hydrogen using flexible pipes?
The task is to transfer hydrogen (high pressure gas > 400 bars) from offshore platform to land. To do so we have to use flexible pipes but for high pressure and high flow rate I'm afraid we can't ...
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A 40L compressed air cylinder at 100 bar is emptied in pulses at the rate of 41kg/s. How many such cycles would it take to empty the cylinder? [closed]
I am constructing a blowback gas system where clogged debris needs to be removed with compressed air using compressed air cylinder. 40L compressed air cylinder at 100bar pressure is available as ...
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How to transfer compressed gas GH2 from one tank to another at the same pressure?
The problem is to transfer all the compressed hydrogen from one tank on a ship at 400 bars to fill another tank on earth (also to fill it at 400 bars). What are the common technologies and equipment (...
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How to calculate the gas flow rate?
I am using a Venturi burner fed using a lpg cylinder. I need to calculate the gas flow rate?
I am thinking of filling the gas in a balloon/fixed container can take the weight before and after to get ...
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If you shut down a gas pipeline for a few months would you fill it with gas at full pressure?
This is of course inspired by the Nordstream gas pipelines in the Baltic Sea. When it was decided that Nordstream 2 would not start operating after construction finished they still filled it with ...
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