6 (b) Throttling 10 kg/s of steam at 20 bar, 250°C reduces the power output of the turbine (a shown in the figure) by 20%. The turbine has an isentropic efficiency of 0.8 and the ex pressure of the turbine is 10 kPa. Steam @20 bar, 250°C Throttle Turbine 10 kPa i. Compute the power output when the steam is not throttled. ii. Compute the quality and enthalpy at the exit of the turbine in the throttlec operation. iii. Compute the rate of irreversibility in the throttle, taking the ambient temperature to be 300 K. v (m/kg) h (kJ/kg) 2902.46 s (kJ/kgK) T°C P bar u (kJ/kg) 250 20 0.11144 2679.58 6.5452 hig (kJ/kg) St (kJ/kg-K) Stg (kJ/kg-K) 7.5010 P kPa T°C h; (kJ/kg) 10 45.81 191.81 2392.82 0.6492

6 (b) Throttling 10 kg/s of steam at 20 bar, 250°C reduces the power output of the turbine (a shown in the figure) by 20%. The turbine has an isentropic efficiency of 0.8 and the ex pressure of the turbine is 10 kPa. Steam @20 bar, 250°C Throttle Turbine 10 kPa i. Compute the power output when the steam is not throttled. ii. Compute the quality and enthalpy at the exit of the turbine in the throttlec operation. iii. Compute the rate of irreversibility in the throttle, taking the ambient temperature to be 300 K. v (m/kg) h (kJ/kg) 2902.46 s (kJ/kgK) T°C P bar u (kJ/kg) 250 20 0.11144 2679.58 6.5452 hig (kJ/kg) St (kJ/kg-K) Stg (kJ/kg-K) 7.5010 P kPa T°C h; (kJ/kg) 10 45.81 191.81 2392.82 0.6492

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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