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Q3. A single-acting, TWO stage reciprocating air compressor fs designed for minimum work with perfect intercooling, and the LP cylinder has a volumetric efficiency of 94%. The compressor delivers 5.8 kg/min of air from an initial cond1t1on of 1.013S bar and 18°C.

In each stage the clearance volume is 4% of the respective swept volume, and the index for all compressions and expansions is n = 1. 37.

The speed of rotation is 420 r/min.

(a) Sketch the cycle on a pressure-volume diagram.

{b) Determine EACH of the following:

(i) the delivery pressure;

(ii) the power;

(iii} the volume per cycle for the LP stage.

Note: For air C_v = 0.718kJ/kgK C_p = 1. 005kJ I kgK