Air is compressed from 14.7 psia and 60°F to a pressure of 150 psia while being cooled at a rate of 10 Btu/lbm by circulating water through the compressor casing. The volume flow rate of the air at the inlet conditions is 5000 ft³/min, and the power input to the compressor is 700 hp. Determine:(a) the mass ow rate of the air and (b) the temperature at the compressor exit.

A. 6.36 lbm/s

b.

Explanation:

a. Given the following information;

#Compressor inlet:

Air pressure,

#Compressor outlet:

#Cooling rate,

# From table A-1E

Gas constant of air

Specific enthalpy at

Using the mass balance:

Hence, the mass flow rate of the air is 6.36lbm/s

b The specific enthalpy at the exit is defined as the energy balance on the system:

Hence, the temperature at the compressor exit

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