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Q8. A two-stage single acting reciprocating compressor is water cooled and runs at a speed of 240 rev/min. The pressure and temperature at the first stage inlet are 1 bar and 15℃ respectively. The second stage inlet conditions are 6 bar and 27℃.

The air leaves the machine at a pressure of 30 bar and temperature of 60℃.

The total mass of air in the low- pressure cylinder at the beginning of compression is 0.025 kg and the clearance ratio is 0.05. The polytropic index for all expansion and compression processes is 1.25. Calculate EACH of the following:

(a) the total indicated power; (8)

(b) the total heat removed per cycle from the cylinder;(5)

(c) the total heat removed per cycle by the coolers.(3)

Note: for air, γ = 1.4 , C_V = 0.7175  kJ⁄(kg K)