Steam turbine engines are connected in pairs at a power plant so that the heat output of the first engine is used as the heat input of the second. The operating temperatures of the first engine are 676 °C and 424 °C and of the second, 414 °C and 286 °C. If the plant's target is to produce 1000 MW of power, estimate the rate in kg/s at which coal should be burned. Coal's heat of combustion is 2.8 x 107 J/kg. Assume the efficiency of the engines is 66.7 percent of the ideal (Carnot) efficiency. Begin by finding the efficiency of each engine. Your goal is to find Qh,1, the rate of heat input to the first engine. Use the facts that the total power supplied by the plant is the sum of the power supplied by each engine, that the heat input to the second engine equals the heat output of the first, and that the efficiency of each engine is the ratio of its work output to its heat input

Steam turbine engines are connected in pairs at a power plant so that the heat output of the first engine is used as the heat input of the second. The operating temperatures of the first engine are 676 °C and 424 °C and of the second, 414 °C and 286 °C. If the plant's target is to produce 1000 MW of power, estimate the rate in kg/s at which coal should be burned. Coal's heat of combustion is 2.8 x 107 J/kg. Assume the efficiency of the engines is 66.7 percent of the ideal (Carnot) efficiency. Begin by finding the efficiency of each engine. Your goal is to find Qh,1, the rate of heat input to the first engine. Use the facts that the total power supplied by the plant is the sum of the power supplied by each engine, that the heat input to the second engine equals the heat output of the first, and that the efficiency of each engine is the ratio of its work output to its heat input

University Physics Volume 2

18th Edition

ISBN:9781938168161

Author:OpenStax

Publisher:OpenStax

Chapter4: The Second Law Of Thermodynamics

Section: Chapter Questions

Problem 67AP: A 300-W heat pump operates between the ground, whose temperature is 0 , and the interior of a house...

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