Fuel used in a residential furnace is natural gas, which enters the furnace at 20°C and 1 atm. A volumetric analysis of the natural gas shows that it is composed of methane, nitrogen, and water vapor with composition 0.90, 0.09, and 0.01, respectively. The natural gas is combusted with 75% excess air that enters at 25°C, 1 atm, and 60% relative humidity. The gas flow rate is adjusted so that the combustion products leave the furnace at 190°C in order to promote exhaust gas removal by buoyancy and avoid condensation in the chimney. The exit pressure is 1 atm. Determine the efficiency of this furnace, which is defined as the ratio of the output thermal energy power to the higher heating value of the fuel.

Fuel used in a residential furnace is natural gas, which enters the furnace at 20°C and 1 atm. A volumetric analysis of the natural gas shows that it is composed of methane, nitrogen, and water vapor with composition 0.90, 0.09, and 0.01, respectively. The natural gas is combusted with 75% excess air that enters at 25°C, 1 atm, and 60% relative humidity. The gas flow rate is adjusted so that the combustion products leave the furnace at 190°C in order to promote exhaust gas removal by buoyancy and avoid condensation in the chimney. The exit pressure is 1 atm. Determine the efficiency of this furnace, which is defined as the ratio of the output thermal energy power to the higher heating value of the fuel.

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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