9th Edition

ISBN: 9781260048766

Author: CENGEL

Publisher: MCG

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Chapter 10.9, Problem 117RP

Show that the thermal efficiency of a combined gas–steam power plant ηcc can be expressed as

η ∞ = η g + η s − η g η s

where ηg = Wg /Qin and η_s = W_s/Q_g_,out are the thermal efficiencies of the gas and steam cycles, respectively. Using this relation, determine the thermal efficiency of a combined power cycle that consists of a topping gas-turbine cycle with an efficiency of 40 percent and a bottoming steam-turbine cycle with an efficiency of 30 percent.

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Chapter 10.9, Problem 111RP

Chapter 10.9, Problem 118RP

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Chapter 10 Solutions

Thermodynamics: An Engineering Approach

Ch. 10.9 - Why is the Carnot cycle not a realistic model for...Ch. 10.9 - Why is excessive moisture in steam undesirable in...Ch. 10.9 - A steady-flow Carnot cycle uses water as the...Ch. 10.9 - A steady-flow Carnot cycle uses water as the...Ch. 10.9 - Consider a steady-flow Carnot cycle with water as...Ch. 10.9 - Water enters the boiler of a steady-flow Carnot...Ch. 10.9 - What four processes make up the simple ideal...Ch. 10.9 - Consider a simple ideal Rankine cycle with fixed...Ch. 10.9 - Consider a simple ideal Rankine cycle with fixed...Ch. 10.9 - Consider a simple ideal Rankine cycle with fixed...

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Solution Summary: The author explains that the expression for the thermal efficiency of a combined gas-steam power plant is 58%.

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