Steam enters a turbine at 100 bars and 400°C. At the exit the pressure is 1.0 bar and the entropy has increased by 0.600 kJ/kg · K under adiabatic conditions. The changes in kinetic and potential energies may be neglected. (a) Determine the work, in kJ/kg. For the same initial conditions and final pressure the turbine is now run without insulation. The entropy production due to internal irreversibilities is assumed to be the same as in part (a). However, the environment at 300 K is found to have an entropy change of +0.0800 kJ/(kg steam) · K. Also, the entropy change of the steam due to heat exchange with the environment has an absolute value of 0.0460 kJ/kg K. (b) Determine the quality of the steam at the turbine outlet, and compare to the answer from part (a). Also, (c) determine the heat transfer to the environment,

Steam enters a turbine at 100 bars and 400°C. At the exit the pressure is 1.0 bar and the entropy has increased by 0.600 kJ/kg · K under adiabatic conditions. The changes in kinetic and potential energies may be neglected. (a) Determine the work, in kJ/kg. For the same initial conditions and final pressure the turbine is now run without insulation. The entropy production due to internal irreversibilities is assumed to be the same as in part (a). However, the environment at 300 K is found to have an entropy change of +0.0800 kJ/(kg steam) · K. Also, the entropy change of the steam due to heat exchange with the environment has an absolute value of 0.0460 kJ/kg K. (b) Determine the quality of the steam at the turbine outlet, and compare to the answer from part (a). Also, (c) determine the heat transfer to the environment,

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

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