How to find power required for adiabatic compressor?(adsbygoogle = window.adsbygoogle || []).push({});

Problem - Air enters an adiabatic compressor at 20 C and 1bar. The volumetric flow rate of air is 1 m3/s and it exits at 200 C. Determine the power required if the isentropic efficiency of the compressor is 80%.

Density of water = 1000 kg/m^3

Mass flow rate m = 1 m^3/s * 1000 kg/m^3 = 1000 kg/s

I know that power output is calculated by

m Cp (T2 - T1)

But what is meant by power required? Is it same as power output or is it power input?

If it is power output, then we can calculate it using m Cp (T2 - T1)

If it is power input, then can we use work required = power output/(isentropic efficiency) ?

The problem involves a range of temperatures. I have to use the values of density, Cp and any other constants needed at what temperature? Initial? Final? Average?

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# Thermodynamics question - does power required mean same as power output?

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