A boiler is supplied with 15, 900 kg of feed water at1 5°C, during a trial period of 8 hours and 20 minutes. At the end of the trial, the weight of water was 680 kg less than that of commencement of trial. The steam produced at the pressure of 12. 5 bar is 95% dry. The coal having the calorific value of 30,000 kJ/kg is fired at the rate of 275.8 kg/h. Calculate (a) actual evaporation rate, (b) equivalent evaporation, and (c) thermal efficiency of the boiler.

A boiler is supplied with 15, 900 kg of feed water at1 5°C, during a trial period of 8 hours and 20 minutes. At the end of the trial, the weight of water was 680 kg less than that of commencement of trial. The steam produced at the pressure of 12. 5 bar is 95% dry. The coal having the calorific value of 30,000 kJ/kg is fired at the rate of 275.8 kg/h. Calculate (a) actual evaporation rate, (b) equivalent evaporation, and (c) thermal efficiency of the boiler.

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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