Thermodynamics: An Engineering Approach
9th Edition
ISBN: 9781259822674
Author: Yunus A. Cengel Dr., Michael A. Boles
Publisher: McGraw-Hill Education
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Textbook Question
Chapter 10.9, Problem 75P
A large food-processing plant requires 1.5 lbm/s of saturated or slightly superheated steam at 140 psia, which is extracted from the turbine of a cogeneration plant. The boiler generates steam at 800 psia and 1000°F at a rate of 10 lbm/s, and the condenser pressure is 2 psia. Steam leaves the process heater as a saturated liquid. It is then mixed with the feedwater at the same pressure, and this mixture is pumped to the boiler pressure. Assuming both the pumps and the turbine have isentropic efficiencies of 91 percent, determine (a) the rate of heat transfer to the boiler and (b) the power output of the cogeneration plant.
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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...
Ch. 10.9 - How do actual vapor power cycles differ from...Ch. 10.9 - Compare the pressures at the inlet and the exit of...Ch. 10.9 - The entropy of steam increases in actual steam...Ch. 10.9 - Is it possible to maintain a pressure of 10 kPa in...Ch. 10.9 - A simple ideal Rankine cycle with water as the...Ch. 10.9 - A simple ideal Rankine cycle with water as the...Ch. 10.9 - A simple ideal Rankine cycle which uses water as...Ch. 10.9 - Consider a solar-pond power plant that operates on...Ch. 10.9 - Consider a 210-MW steam power plant that operates...Ch. 10.9 - Consider a 210-MW steam power plant that operates...Ch. 10.9 - A simple ideal Rankine cycle with water as the...Ch. 10.9 - A simple ideal Rankine cycle with water as the...Ch. 10.9 - A steam Rankine cycle operates between the...Ch. 10.9 - A steam Rankine cycle operates between the...Ch. 10.9 - A simple Rankine cycle uses water as the working...Ch. 10.9 - The net work output and the thermal efficiency for...Ch. 10.9 - A binary geothermal power plant uses geothermal...Ch. 10.9 - Consider a coal-fired steam power plant that...Ch. 10.9 - Show the ideal Rankine cycle with three stages of...Ch. 10.9 - Is there an optimal pressure for reheating the...Ch. 10.9 - How do the following quantities change when a...Ch. 10.9 - Consider a simple ideal Rankine cycle and an ideal...Ch. 10.9 - Consider a steam power plant that operates on the...Ch. 10.9 - Consider a steam power plant that operates on the...Ch. 10.9 - An ideal reheat Rankine cycle with water as the...Ch. 10.9 - Steam enters the high-pressure turbine of a steam...Ch. 10.9 - An ideal reheat Rankine cycle with water as the...Ch. 10.9 - A steam power plant operates on an ideal reheat...Ch. 10.9 - Consider a steam power plant that operates on a...Ch. 10.9 - Repeat Prob. 1041 assuming both the pump and the...Ch. 10.9 - Prob. 43PCh. 10.9 - Prob. 44PCh. 10.9 - How do open feedwater heaters differ from closed...Ch. 10.9 - How do the following quantities change when the...Ch. 10.9 - Cold feedwater enters a 200-kPa open feedwater...Ch. 10.9 - In a regenerative Rankine cycle. the closed...Ch. 10.9 - A steam power plant operates on an ideal...Ch. 10.9 - A steam power plant operates on an ideal...Ch. 10.9 - A steam power plant operates on an ideal...Ch. 10.9 - Consider an ideal steam regenerative Rankine cycle...Ch. 10.9 - Consider a steam power plant that operates on the...Ch. 10.9 - Consider a steam power plant that operates on the...Ch. 10.9 - Consider a steam power plant that operates on the...Ch. 10.9 - A steam power plant operates on an ideal...Ch. 10.9 - Repeat Prob. 1060, but replace the open feedwater...Ch. 10.9 - A steam power plant operates on an ideal...Ch. 10.9 - A simple ideal Rankine cycle with water as the...Ch. 10.9 - Prob. 64PCh. 10.9 - An ideal reheat Rankine cycle with water as the...Ch. 10.9 - Consider a steam power plant that operates on a...Ch. 10.9 - Prob. 67PCh. 10.9 - A steam power plant operates on an ideal...Ch. 10.9 - The schematic of a single-flash geothermal power...Ch. 10.9 - What is the difference between cogeneration and...Ch. 10.9 - Prob. 71PCh. 10.9 - Prob. 72PCh. 10.9 - Consider a cogeneration plant for which the...Ch. 10.9 - Steam is generated in the boiler of a cogeneration...Ch. 10.9 - A large food-processing plant requires 1.5 lbm/s...Ch. 10.9 - An ideal cogeneration steam plant is to generate...Ch. 10.9 - Steam is generated in the boiler of a cogeneration...Ch. 10.9 - Consider a cogeneration power plant modified with...Ch. 10.9 - Prob. 80PCh. 10.9 - Why is the combined gassteam cycle more efficient...Ch. 10.9 - The gas-turbine portion of a combined gassteam...Ch. 10.9 - A combined gassteam power cycle uses a simple gas...Ch. 10.9 - Reconsider Prob. 1083. An ideal regenerator is...Ch. 10.9 - Reconsider Prob. 1083. Determine which components...Ch. 10.9 - Consider a combined gassteam power plant that has...Ch. 10.9 - Prob. 89PCh. 10.9 - What is the difference between the binary vapor...Ch. 10.9 - Why is mercury a suitable working fluid for the...Ch. 10.9 - Why is steam not an ideal working fluid for vapor...Ch. 10.9 - By writing an energy balance on the heat exchanger...Ch. 10.9 - Prob. 94RPCh. 10.9 - Steam enters the turbine of a steam power plant...Ch. 10.9 - Consider a steam power plant operating on the...Ch. 10.9 - A steam power plant operates on an ideal Rankine...Ch. 10.9 - Consider a steam power plant that operates on a...Ch. 10.9 - Repeat Prob. 1098 assuming both the pump and the...Ch. 10.9 - Consider an ideal reheatregenerative Rankine cycle...Ch. 10.9 - Prob. 101RPCh. 10.9 - A textile plant requires 4 kg/s of saturated steam...Ch. 10.9 - Consider a cogeneration power plant that is...Ch. 10.9 - Prob. 104RPCh. 10.9 - Prob. 105RPCh. 10.9 - Reconsider Prob. 10105E. 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