Water is the working fluid in a Carnot vapor power cycle. Saturated liquid enters the boiler at a pressure of 10 MPa, and saturated vapor enters the turbine. The condenser pressure is 8 kPa. The effects of irreversibilities in the adiabatic expansion and the compression processes are taken into consideration. The turbine and pump efficiencies are 80% and 75%, respectively. Determine (a) the thermal efficiency, (b) the back work ratio, (c) the heat transfer to the working fluid per unit mass passing through the boiler in kJ/kg and (d) the heat transfer from the working fluid per unit mass passing through the condenser in kJ/kg.

Water is the working fluid in a Carnot vapor power cycle. Saturated liquid enters the boiler at a pressure of 10 MPa, and saturated vapor enters the turbine. The condenser pressure is 8 kPa. The effects of irreversibilities in the adiabatic expansion and the compression processes are taken into consideration. The turbine and pump efficiencies are 80% and 75%, respectively. Determine (a) the thermal efficiency, (b) the back work ratio, (c) the heat transfer to the working fluid per unit mass passing through the boiler in kJ/kg and (d) the heat transfer from the working fluid per unit mass passing through the condenser in kJ/kg.

Refrigeration and Air Conditioning Technology (MindTap Course List)

8th Edition

ISBN:9781305578296

Author:John Tomczyk, Eugene Silberstein, Bill Whitman, Bill Johnson

Publisher:John Tomczyk, Eugene Silberstein, Bill Whitman, Bill Johnson

Chapter28: Special Refrigeration Applications

Section: Chapter Questions

Problem 15RQ: Why is two-stage compression popular for extra-low-temperature refrigeration systems?

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