2. An R22 standard refrigeration system carries a refrigerating load of 82 kW. The suction and discharge pressures of the compressor are 354.3 kPa and 1460.1 kPa respectively. The liquid refrigerant is subcooled by 4• before entering the expansion valve and the vapor is superheated by 5º before entering the compressor. The twin- cylinder, single-acting efficiency, 82%; clearance volume, 6%; and mechanical efficiency, 78% compressor operates at 1680 rpm; stroke-to-bore ratio, 1.20; actual volumetric Determine (a) mass flow rate of refrigerant in kg/s (b) mass flow rate of refrigerant per ton of refrigeration in kg/s-ton (r) work on comnressor in kW

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

A two stage cascade refrigeration system uses R-12 in the high pressure loop with a condenser temperature of 300C and -100C in the cascade condenser, and R-22 in the low pressure loop with a temperature in the cascade condenser of 00C and an evaporator temperature of -30 0C. The refrigeration load is 28 tons. h6 = 366 kJ/kg;    h2= 421 kJ/kg Determine the ff:a.) the mass flow rate in the low pressure loop,ANSWER: 0.5097287949549 kg/s b.) the mass flow rate in the high pressure loop,ANSWER: 0.94987995754451 kg/s c.) total power requirementANSWER: 32.1224 KW

please include Ps and Th diagram