A power plant has a turbogenerator, operating at steady state with an input shaft rotating at 1800 RPM with a torque of 16,700 N-m. The turbogenerator produces current at 230 amp with a voltage of 13,000 V. The rate of heat transfer between the turbogenerator and its surroundings is related to the surface temperature Tp and the lower ambient temperature To and is given by Q = - h A (Tb - To), where h = 100 W/m2.K, A = 25 m2, and To = %3D 298 K. (a) [10] Determine the temperature Tp, in K. (b) [10] For the turbogenerator as the system, determine the rate of entropy production, in kW/K.

A power plant has a turbogenerator, operating at steady state with an input shaft rotating at 1800 RPM with a torque of 16,700 N-m. The turbogenerator produces current at 230 amp with a voltage of 13,000 V. The rate of heat transfer between the turbogenerator and its surroundings is related to the surface temperature Tp and the lower ambient temperature To and is given by Q = - h A (Tb - To), where h = 100 W/m2.K, A = 25 m2, and To = %3D 298 K. (a) [10] Determine the temperature Tp, in K. (b) [10] For the turbogenerator as the system, determine the rate of entropy production, in kW/K.

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter10: Heat Exchangers

Section: Chapter Questions

Problem 10.17P

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