temperature increase with compressing air?
temperature increase with compressing air?
(OP)
Forgive me for my ignorance, but I havent had a formal thermodynamics class. I believe that the temperature of air increases as it is compressed, but I would like to know by how much. Is there a formula based on volume, intake air temp, and compression amount? Basically I'd like to know how hot the air is when compressed to 120psi. If my calculations are correct, it would need to compress about 6 cubic feet of air per second.





RE: temperature increase with compressing air?
For air, the absolute temp ratio will be the power ~.4/1.4 or .285 of the pressure ratio.
So, using a calc, the absolute temp ratio:
9.16^.285 = 1.88
If you start out with a temp of 70F, the abs temp is 70+459=529R. the abs temp after compression will be 529 X 1.88 = 994R
Bringing it back to F, 994R - 459 = 535F
Of course, much of the heat will be lossed in the compressor, so the temp will actually be lower.
A more exact exponent for air is .283, reducing the temp a little.
RE: temperature increase with compressing air?
For air, you can estimate it as
dT = T1 * [(P2/P1)^0.286 - 1]/eff
dT is the temperature rise
T1 is the inlet temperature, degrees absolute
P2 is the final pressure, absolute, not gauge
P1 is the inlet pressure, absolute, not gauge
eff is the efficiency of compression.
RE: temperature increase with compressing air?
give me exact definitions of Entropy.
RE: temperature increase with compressing air?
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