# A 45,000 Btu/h refrigeration system operates on the ideal vapor-compression refrigeration cycle with

A 45,000 Btu/h refrigeration system operates on the ideal vapor-compression refrigeration cycle with R-22 as the refrigerant. The evaporator pressure is 150 kPa and the condenser pressure is 1500 kPa. The refrigerant exchanges heat with air at ?5 ?C in the evaporator and with air at 19 ?C in the condenser. If the air conditioner operates at full cooling load, determine (a) the mass flow rate of R-22, (b) the power input and the COP, and (c) the second-law efficiency of the cycle and the total exergy destruction in the cycle. The enthalpies of R-22 at various states are given as (R-22 tables are not available in the text): h1 = 391.58 kJ/kg, s1 = 1.8051 kJ/kg·K, h2 = 450.98 kJ/kg, h3 = 248.58 kJ/kg, s3 = 1.1632 kJ/kg·K, h4 = 248.58 kJ/kg, s4 = 1.2119 kJ/kg·K. Take T0 = 19 ?C