2. (#6-DimagPP18) A reheat regenerative steam cycle operates with condenser pressure of 0.007 MPa. Steam at 13.5 MPa and 540 C leaves the steam generator and enters the turbine at 13 MPa and 540 ■C. Expansion takes place in the turbine to a pressure of 3.45 MPa and a temperature of 350 C. At this condition, the steam is re-heated at constant pressure to a temperature of 480 C. The reheated steam expands to 0.70 MPa and 260 C where a portion of steam is extracted to an open feedwater heater. The remaining steam continues to expand to an exhaust pressure of 0.007 MPa and a quality of 88%. Neglecting the effect of pump work, determine: a) QA b) Work of the turbine c) The thermal efficiency of the engine

2. (#6-DimagPP18) A reheat regenerative steam cycle operates with condenser pressure of 0.007 MPa. Steam at 13.5 MPa and 540 C leaves the steam generator and enters the turbine at 13 MPa and 540 ■C. Expansion takes place in the turbine to a pressure of 3.45 MPa and a temperature of 350 C. At this condition, the steam is re-heated at constant pressure to a temperature of 480 C. The reheated steam expands to 0.70 MPa and 260 C where a portion of steam is extracted to an open feedwater heater. The remaining steam continues to expand to an exhaust pressure of 0.007 MPa and a quality of 88%. Neglecting the effect of pump work, determine: a) QA b) Work of the turbine c) The thermal efficiency of the engine

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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