The evaporator of a refrigeration cycle is basically a heat exchanger in which a refrigerant is evaporated by absorbing heat from a fluid. Refrigerant-22 enters an evaporator at 200 kPa with a quality of 22 percent and a flow rate of 2.65 L/h. R-22 leaves the evaporator at the same pressure superheated by 5°C. The refrigerant is evaporated by absorbing heat from air whose flow rate is 0.75 kg/s. Determine
(a) The rate of heat absorbed from the air and
(b) The temperature change of air. The properties of R-22 at the inlet and exit of the condenser are h1 = 220.2 kJ/kg, v1 5 0.0253 m3/kg, and h2 = 398.0 kJ/kg.