An ammonia refrigeration plant operates between a condensing temperature of 40C and an evaporating temperature of -10C. The vapour is dry at the end of compression. Only the following property values are given: 40C -10C kJ/kg 371.5 135.4 ing kJ/kg 1473 1433 58 kJ/kg.K 1.36 0.544 The specific heat of NH, vapour is 2.1897 kJ/kg.K. Calculate the theoretical coefficient of performance of the cycle. A R134a machine operates at -15C evaporator and 35C condenser temperatures. Assuming a simple-saturation cycle, calculate the volume of the suction vapour and power consumption per ton of refrigeration and COP of the cycle. Calculate the same if the system has a regenerative heat exchanger with the suction vapour leaving at 20C from the heat exchanger. (a) What would be the necessary bore and stroke of a single acting four- cylinder, 350 rpm ammonia compressor working on simple saturation cycle between 35C condenser and -15C evaporator temperatures and developing 15 tons refrigeration. Given for the compressor: Ratio of stroke to bore 1 Volumetric efficiency = 0.7 (b) If the index of compression is 1.15, find the error introduced in calculating the work of compression by assuming the process to be isentropic. Also, find the heat rejected to the compressor-jacket cooling water.