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Q8. A two-stage single acting reciprocating gas compressor has a clearance ratio of 0.045 and runs at 200 rev/min.

The low-pressure cylinder swept volume is 0.0848 m³ and the pressure and temperature at inlet are 0.9 bar and 20℃ respectively.

The maximum temperature of the gas is limited to 180℃.

The polytropic index of expansion and compression is 1.28 in both stages and intercooling is perfect.

(a) Sketch the cycle on a Pressure- Volume diagram indicating ALL the volumes.(2)

(b) Calculate EACH of the following:

(i) The inter-stage and delivery pressures;(2)

(ii) The volumetric efficiency;(2)

(iii) The indicated power;(5)

(iv) The rate of heat removal in the intercooler.(5)

Note: for the gas, molecular mass M = 4.003 kg/kmol, C_P = 5.193 kJ/kg K

Universal gas constant R_o = 8.3145 kJ/kmol K