Steam heated at constant pressure in a steam generator enters the first stage of a supercritical reheat cycle at 28 MPa, 520°C. Steam exiting the first-stage turbine at 6 MPa is reheated at constant pressure to 500°C. Each turbine stage has an isentropic efficiency of 90% while the pump has an isentropic efficiency of 82%. Saturated liquid exits the condenser that operates at a constant pressure of 38 kPa. Determine: (a) the quality of the steam exiting the second stage of the turbine. (b) the percent thermal efficiency.

Steam heated at constant pressure in a steam generator enters the first stage of a supercritical reheat cycle at 28 MPa, 520°C. Steam exiting the first-stage turbine at 6 MPa is reheated at constant pressure to 500°C. Each turbine stage has an isentropic efficiency of 90% while the pump has an isentropic efficiency of 82%. Saturated liquid exits the condenser that operates at a constant pressure of 38 kPa. Determine: (a) the quality of the steam exiting the second stage of the turbine. (b) the percent thermal efficiency.

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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