Steam enters a turbine with a pressure of 30 bar and a temperature of 400°C. Saturated vapor at 100°C exits the turbine. At steady state, the turbine develops work equal to 532.2 kJ per kg of steam flowing through the turbine. Heat transfer between the turbine and its surroundings occurs at an average outer surface temperature of 350 K. Neglect the change in potential and kinetic energy between inlet and exit. Determine (a) the heat transferred between the turbine and its surroundings, per kg of steam flowing, (b) the rate at which entropy is produced within the turbine per kg of steam flowing, in kJ/kg ·K.

Steam enters a turbine with a pressure of 30 bar and a temperature of 400°C. Saturated vapor at 100°C exits the turbine. At steady state, the turbine develops work equal to 532.2 kJ per kg of steam flowing through the turbine. Heat transfer between the turbine and its surroundings occurs at an average outer surface temperature of 350 K. Neglect the change in potential and kinetic energy between inlet and exit. Determine (a) the heat transferred between the turbine and its surroundings, per kg of steam flowing, (b) the rate at which entropy is produced within the turbine per kg of steam flowing, in kJ/kg ·K.

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

Chapter45: Domestic Refrigerators And Freezers

Section: Chapter Questions

Problem 12RQ: Refrigerators currently being manufactured in the United States are using______as their refrigerant.

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