DieselShip's Online Content Library

Q6. A vapour compression refrigeration plant uses R134a as the working fluid.

The refrigerant enters the compressor as a dry saturated vapour at a temperature of -20℃ and leaves at a pressure of 11.595 bar.

The isentropic efficiency of the compressor is 86.4 % and the refrigerant enters the expansion valve at 40℃.

Sea water flows through the condenser at the rate of 5 m³/hour and increases in temperature by 10 K. Calculate EACH of the following:

(a) The temperature of the refrigerant at the end of compression;(5)

(b) The cooling load:(5)

(c) The compressor power;(2)

(d) The coefficient of performance for the cycle;(2)

(e) The COP for the reversed Carnot cycle operating between the same pressures; (2)

Note: for sea water specific heat capacity C = 4.0 kJ/ kg K

Density ρ = 1025 kg/m³.