A new commercial refrigerator-freezer combination unit is being designed with a dual-evaporator system. The freezer compartment is to be at -24.0°C and the refrigerator compartment is to be at 8.00°C. The outlet of the condenser is at 26.0°C.
The cooling capacities of both the refrigerating and the freezer compartments are to be 800. kJ/h each. The system uses refrigerant R-134a with a compressor isentropic efficiency of 89.0%. Determine
a. The coefficient of performance for this design.
b. The mass flow rate of refrigerant required.
c. The quality at the outlet of the refrigeration evaporator.