: The boiler of a power steam cycle operates at 6000 kPa and the condenser at 50 kPa. At the entrance to the turbine, the temperature is 500°C. The isentropic efficiency of the turbine is 90 percent, pressure and pump losses are negligible, and the water leaving the condenser is subcooled by 6.3°C. The boiler is sized for a mass flow rate of 18 kg/s. You are asked to: a. Represent the c

: The boiler of a power steam cycle operates at 6000 kPa and the condenser at 50 kPa. At the entrance to the turbine, the temperature is 500°C. The isentropic efficiency of the turbine is 90 percent, pressure and pump losses are negligible, and the water leaving the condenser is subcooled by 6.3°C. The boiler is sized for a mass flow rate of 18 kg/s. You are asked to: a. Represent the c

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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2. A steam power plant operates on the Rankine cycle in which the steam enters the turbine at 16 MPa and 600°C and the condensate leaves the condenser at 10 kPa. If the isentropic efficiency of the turbine is 87 percent and the isentropic efficiency of the pump is 85 percent, determine (a) the thermal efficiency of the cycle and (b) the net power output of the plant for a mass flow rate of 15 kg/s.
A steam power plant operates on a simple ideal Rankine cycle between the pressure limits of 1250 and 2 psia. The mass flow rate of steam through the cycle is 75 lbm/s. The moisture content of the steam at the turbine exit is not to exceed 10 percent. Show the cycle on a T-s diagram with respect to saturation lines, and determine (a) the minimum turbine inlet temperature, (b) the rate of heat input in the boiler, and (c) the thermal efficiency of the Cycle. Answers:
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