The vapor compression heat pump system uses R134a as the working fluid. The inlet conditions of the refrigerant to the compressor are 2.4 bar, 0oC and its volumetric flow rate is 0.6 m3 / min. Compression is adiabatic and lasts up to 9 bar and 60oC conditions. From the condenser The exit conditions (from the condenser) are 9 bars of saturated liquid. Under these conditions; a) Calculate the heating capacity of the system in kW. b) Calculate the heating efficiency coefficient (COPIP) of the system. c) Calculate the adiabatic efficiency of the compressor.

Refrigerant 22 is the working fluid in a Carnot vapor refrigeration cycle for which the evaporator temperature is -30°C. Saturated vapor enters the condenser at 36°C, and saturated liquid exits at the same temperature. The mass flow rate of refrigerant is 10 kg/min. Determine the quality of refrigerant at inlet of compressor,

The figure below shows a two-stage vapor-compression refrigeration system with ammonia as the working fluid. The system uses a direct-contact heat exchanger to achieve intercooling. The evaporator has a refrigerating capacity of 40 tons and produces -30°F saturated vapor at its exit. In the first compressor stage, the refrigerant is compressed adiabatically to 140 lbf/in.², which is the pressure in the direct contact heat exchanger. Saturated vapor at 140 lbf/in.² enters the second compressor stage and is compressed adiabatically to 250 lbf/in.² Each compressor stage has an isentropic efficiency of 85%. There are no significant pressure drops as the refrigerant passes through the heat exchangers. Saturated liquid enters each expansion valve. Determine: Expansion valve 6- Condenser Direct contact heat exchanger Expansion valve (a) the ratio of mass flow rates, m3/my. (b) the power input to each compressor stage, in horsepower. (c) the coefficient of performance Comp Comp Evaporator

9. A vapour compression plant is powered by a 2kW motor and circulates R12 at 5kg/min. The R12 leaves the condenser at its saturation temperature with a specific enthalpy of 74.59kJ/kg and leaves the evaporated dry saturated with a specific enthalpy of 187.53kJ/kg. Calculate: (a). the dryness fraction at the evaporator inlet (b). refrigeration effect (c). coefficient of performance