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Q16. At the beginning of compression in a single stage, single acting reciprocating air compressor, the air is at a pressure of 1.01 bar and a temperature of 28°C. The delivery valve opens at a pressure of 6.2 bar. The delivery temperature is 175°C. The bore diameter and stroke length are 0.25 m and 0.32 m respectively. The clearance volume is 4% of the swept volume and the compressor runs at 500 rev/min.

(a) Sketch the p-V diagram.

(b) Determine EACH of the following:

(i) the index of compression

(ii) the volumetric efficiency

(iii) the indicated work per kg of air

(iv) the free air capacity in m³/min, given that free air conditions are 1.03 bar and 25°C.

Note: For air, R = 0.287KJ/kg K.