Chapter 6, Problem 6.93P

Water vapor at 10 MPa, 600°C enters a turbine operating at steady state with a volumetric flow rate of 0.36 m/s and exits at 0.1 bar and a quality of 92%. Stray heat transfer and kinetic and potential energy effects are negligible. Determine for the turbine (a) the mass flow rate, in kg/s, (b) the power developed by the turbine, in MW, (c) the rate at which entropy is produced, in kW/K, and (d) the isentropic turbine efficiency. Show this expansion process on a T-s diagram.

Water vapor at 10 MPa, 600°C enters a turbine operating at a steady state with a volumetric flow rate of 0.36 m3/sand exits at 0.1 bar and a quality of 92%. Stray heat transfer and kinetic and potential energy effects are negligible. Determine for the turbine (a) the mass flow rate, in kg/s, (b) the power developed by the turbine, in MW, (c) the rate at which entropy is produced, in kW/K, and (d) the isentropic turbine efficiency. Show this expansion process on a T-s diagram.

Saturated water vapor at 300°F enters a compressor operating at steady state with a mass flow rate of 5 lb/s and is compressed adiabatically to 600 lbf/in.² If the power input is 2150 hp, determine for the compressor: (a) the percent isentropic compressor efficiency and (b) the rate of entropy production, in hp/°R. Ignore kinetic and potential energy effects.

Air is compressed adiabatically in a piston-cylinder assembly from 1 bar, 300 K to 6 bar, 600 K. The air can be modeled as an ideal gas and kinetic and potential energy effects are negligible. Determine the amount of entropy produced, in kJ/K per kg of air, for the compression. What is the minimum theoretical work input, in kJ per kg of air, for an adiabatic compression from the given initial state to a final pressure of 6 bar? Note that work is positive into the compressor. Part A Determine the amount of entropy produced, in kJ/K per kg of air, for the compression. o/m = i kJ/K

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Refrigerant 134a enters a horizontal pipe operating at steady state at 40°C, 300 kPa, and a velocity of 40 m/s. At the exit, the temperature is 90°C and the pressure is 240 kPa. The pipe diameter is 0.01 m. Determine: (a) the mass flow rate of the refrigerant, in kg/s, (b) the velocity at the exit, in m/s, and (c) the rate of heat transfer between the pipe and its surroundings, in kW. Part A X Your answer is incorrect. Determine the mass flow rate of the refrigerant, in kg/s. i ! kg/s

Refrigerant 22 flows through a horizontal tube having an inside diameter of 4 cm. Therefrigerant flows at steady state and at the entrance to the tube it has with a quality of 0.3,temperature of 28°C, and velocity of 8 m/s. The refrigerant exits the tube as a saturatedliquid at 14 bar.Question:Determine:(a) the mass flow rate of the refrigerant, in kg/s.(b) the velocity of the refrigerant at the exit, in m/s.(c) the rate of heat transfer, in kW, and its associated direction with respect to therefrigerant

Water vapor enters a turbine operating at steady state at 1000°F, 150 lb:/in?, with a volumetric flow rate of 25 ft³/s, and expands reversibly and adiabatically to 2 Ibf/in?. Ignore kinetic and potential energy effects. Determine the mass flow rate, in Ib/s, and the power developed by the turbine, in hp.