1- A boiler plant comprises a boiler, superheater, economizer and air preheater. The feedwater enters the economizer at 45 °C. Air is preheated from a temperature of 15 °C to 150 °C. The steam is generated in the boiler at a pressure of 35 bar, 0.98 dry and leaves the superheater at 350 °C. When using oil of calorific value 42 MJ/kg, the evaporation rate is 10 kg steam per kg fuel and the air to fuel ratio is 20: 1 by mass. Neglecting heat losses and pressure drops, estimate the heat transfer per kg fuel in each component and the plant efficiency. Assume cp for air and flue gas as 1.005 and 1.045 kJ/ kg K, respectively.

1- A boiler plant comprises a boiler, superheater, economizer and air preheater. The feedwater enters the economizer at 45 °C. Air is preheated from a temperature of 15 °C to 150 °C. The steam is generated in the boiler at a pressure of 35 bar, 0.98 dry and leaves the superheater at 350 °C. When using oil of calorific value 42 MJ/kg, the evaporation rate is 10 kg steam per kg fuel and the air to fuel ratio is 20: 1 by mass. Neglecting heat losses and pressure drops, estimate the heat transfer per kg fuel in each component and the plant efficiency. Assume cp for air and flue gas as 1.005 and 1.045 kJ/ kg K, respectively.

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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