A vapor compression refrigerator circulates 4.5 kg of NH3 per hour. Condensation takes place at 30 °C and evaporation at – 15°C. There is no under-cooling of the refrigerant. The temperature after...

A vapor compression refrigerator circulates 4.5 kg of NH3 per hour. Condensation takes place at 30 °C and evaporation at – 15°C. There is no under-cooling of the refrigerant. The temperature after isentropic compression is 75 °C and the specific heat of the superheated vapor is 2.82 kJ/kg K. Determine:

(i) Coefficient of performance.

(ii) Ice produced in kg per hour in the evaporator from water at 20°C and ice at 0 °C. Take: Enthalpy of fusion of ice = 336 kJ/kg, specific heat of water = 4.187 kJ/kg.

(iii) The effective swept volume of the compressor in m³/min.