Question 12.21: A refrigeration cycle uses Freon-12 as the working fluid. Th...

Applied Thermodynamics

A refrigeration cycle uses Freon-12 as the working fluid. The temperature of the refrigerant in the evaporator is – 10°C. The condensing temperature is 40°C. The cooling load is 150 W and the volumetric efficiency of the compressor is 80%. The speed of the compressor is 720 r.p.m. Calculate the mass flow rate of the refrigerant and the displacement volume of the compressor.

Properties of Freon-12

Temperature (°C)	Saturation pressure (MPa)	Enthalpy (kJ/kg)		Specific volume (m³/kg) Saturated vapour
		Liquid	Vapour
– 10 40	0.22 0.96	26.8 74.5	183.0 203.1	0.08 0.02

(GATE)

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