2. Steam enters a reheat-regenerative turbine at 6 MPa and 400 °C. After partial expansion to 1.2 MPa the steam is withdrawn and passed through a reheater until temperature is 350 °C. Steam then re-enters the turbine and expands to 0.2 MPa where m, is extracted for feedwater heating. Remaining steam expands to a condenser pressure of 0.015 MPa. On the basis of 1 kg throttled steam, find: a) W and W,, b) Q, and QR, C) thermal efficiency of the cycle and engine, d) A steam rate of the cycle and engine, e) heat rate

2. Steam enters a reheat-regenerative turbine at 6 MPa and 400 °C. After partial expansion to 1.2 MPa the steam is withdrawn and passed through a reheater until temperature is 350 °C. Steam then re-enters the turbine and expands to 0.2 MPa where m, is extracted for feedwater heating. Remaining steam expands to a condenser pressure of 0.015 MPa. On the basis of 1 kg throttled steam, find: a) W and W,, b) Q, and QR, C) thermal efficiency of the cycle and engine, d) A steam rate of the cycle and engine, e) heat rate

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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