DieselShip's Online Content Library

Q6. A vapour compression refrigeration plant fitted with an expansion valve uses ammonia as the working fluid.

The refrigerant enters the compressor at a pressure of 2.077 bar and is compressed in an isentropic process to a pressure and temperature of 12.37 bar and 132℃ respectively. It enters the expansion valve with 6 degrees of subcooling.

Heat is removed from the condenser at the rate of 540 MJ/hour.

(a) Calculate EACH of the following:

(i) The compressor suction temperature ;(4)

(ii) The compressor power ;(4)

(iii) The cooling load; (2)

(iv) The coefficient of performance. (2)

(b) Sketch The cycle on a Temperature-specific entropy diagram showing the temperatures at the cardinal points. (4)