In a single acting two-stage reciprocating air compressor. 6 kg of air per minute is compressed from 1.013 bar and 17 °C to 10 bar. Both stages have the same pressure ratio and the input cmperature of the second stage is equal to (he input temperature of the first stage (under such circumstances the intercooling is said to he 'complete').

The law of compression and expansion iii both stages is pV'1 = constant. The clearance volume for both stages is 5% of the swept volume and the compressor speed is 360 rev/min The specific gas constant for air is 287 J /kg/K.

(a) Sketch and label a pressure/volume diagram to represent the two stage cycle.

(b) Determine:

(1) the intermediate pressure

(ii) the intermediate temperature

(iii) the indicated power.