1) A piston cylinder arrangement operates at polytropic condition with negligible friction. If the gas having...

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1) A piston cylinder arrangement operates at polytropic condition with negligible friction. If the gas having initial pressure of P1 and volume of V1 expands as its volume doubled by following. PV1.3 Constant relation. Show that the equation given below can express the work done by the system. W=0.623PVi 2) A reversible heat engine operates between two reservoirs at temperatures of 600 C and 40 C. The engine drives a reversible refrigerator, which operates between reservoirs at temperature of 40 C and -20C. The heat transfer to the heat engine is 2000kJ and the net work output of the combined engine- refrigerator plant is 360kJ. Determine the heat transfer to the refrigerant and the net heat transfer to the reservoir at 40C. 3) A compressor in a commercial refrigerator receives R-140a at -25C and unknown quality. The exit is at 2000kPa, 60C and the process is assumed to be reversible and adiabatic. Neglect kinetic energies and find the specific work. 4) Steam enters a turbine with a pressure of 30 bar, a temperature of 400C and a velocity of 160 m/s. Saturated vapor at 100 C exists with a velocity of 100 m/s. At steady state, the turbine develops work equal to 540 kJ/kg. Heat transfer between the turbine and surrounding occurs at an average surrounding temperature of 25 C. A) Determine the entropy generation rate per kg of steam. B) Draw the process on T-s diagram. 1) A piston cylinder arrangement operates at polytropic condition with negligible friction. If the gas having initial pressure of P1 and volume of V1 expands as its volume doubled by following. PV1.3 Constant relation. Show that the equation given below can express the work done by the system. W=0.623PVi 2) A reversible heat engine operates between two reservoirs at temperatures of 600 C and 40 C. The engine drives a reversible refrigerator, which operates between reservoirs at temperature of 40 C and -20C. The heat transfer to the heat engine is 2000kJ and the net work output of the combined engine- refrigerator plant is 360kJ. Determine the heat transfer to the refrigerant and the net heat transfer to the reservoir at 40C. 3) A compressor in a commercial refrigerator receives R-140a at -25C and unknown quality. The exit is at 2000kPa, 60C and the process is assumed to be reversible and adiabatic. Neglect kinetic energies and find the specific work. 4) Steam enters a turbine with a pressure of 30 bar, a temperature of 400C and a velocity of 160 m/s. Saturated vapor at 100 C exists with a velocity of 100 m/s. At steady state, the turbine develops work equal to 540 kJ/kg. Heat transfer between the turbine and surrounding occurs at an average surrounding temperature of 25 C. A) Determine the entropy generation rate per kg of steam. B) Draw the process on T-s diagram.