Why is the compressor work (steady-flow) proportional to the specific heat of the fluid?
Welcome to PF, sorry about the delay.
Maybe you are referring to the ratio or factor of 1.4 in air compressor efficiency.
The air is compressed which also heats it, then passed to an air receiver chamber where it cools, so the pressure drops slightly. That cooling represents a waste of input energy.
Then ask more specific questions as needed.
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