Temperature Drop of Compressed Air Tank
Temperature Drop of Compressed Air Tank
(OP)
Hello all,
I'm busy calculating the time taken to fill a tank to a certain pressure. With the data from the compressor supplier, I've been successful in determining the time taken in IDEAL conditions.
What I'm a little stumped on is the temperature of the tank while the compressor fills it to its desired pressure. In reality, the compressor being used right now leaves the 1 gallon tank in question somewhere near 140-160 Fahrenheit after compressing the tank to 300 psi.
My theoretical calculations leaves the tank at 205 Fahrenheit.
How can I make a reasonable model to mimic the realistic case?
I have a numerical iteration for the theoretical calculation, it would be ideal if I can incorporate a temperature drop within it. What's my best method to approach this?
Thanks!
I'm busy calculating the time taken to fill a tank to a certain pressure. With the data from the compressor supplier, I've been successful in determining the time taken in IDEAL conditions.
What I'm a little stumped on is the temperature of the tank while the compressor fills it to its desired pressure. In reality, the compressor being used right now leaves the 1 gallon tank in question somewhere near 140-160 Fahrenheit after compressing the tank to 300 psi.
My theoretical calculations leaves the tank at 205 Fahrenheit.
How can I make a reasonable model to mimic the realistic case?
I have a numerical iteration for the theoretical calculation, it would be ideal if I can incorporate a temperature drop within it. What's my best method to approach this?
Thanks!





RE: Temperature Drop of Compressed Air Tank
I've filled a lot of vessels with gas in my career. Many times I've seen frost form on the vessel wall at the start of the fill. The frost stops growing when the tank pressure reaches some number around the critical pressure for choked flow (somewhere around half the supply pressure in absolute units for air). Somewhere around half way between the critical pressure and the supply pressure the frost will all be gone, but the temperature of the tank will still be well below the supply temperature. For the last (about) 10% of the fill the temperature of the tank will rise closer to the supply temperature, but cannot exceed supply temp.
David Simpson, PE
MuleShoe Engineering
Law is the common force organized to act as an obstacle of injustice Frédéric Bastiat