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Q4. At the beginning of compression in a single stage, single acting reciprocating air compressor, the air is at a pressure of 0.98 bar and a temperature of 24ºC. When the delivery valve opens, the pressure is 5.5 bar and the temperature is 145ºC. The cylinder has a diameter of 270 mm and the stroke is 300 mm. The clearance Volume is 5% of the swept volume and the compressor runs at a speed of 500 rev/min.

(a) Sketch the process on a p-V diagram.

(b) Calculate EACH of the following:

(i) The index of compression

(ii) The volumetric efficiency

(iii) The indicated power.

(c) Explain how the polytropic index influences the quantity of air delivered.