Thermodynamics: An Engineering Approach
8th Edition
ISBN: 9780073398174
Author: Yunus A. Cengel Dr., Michael A. Boles
Publisher: McGraw-Hill Education
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Chapter 9.12, Problem 38P
An ideal Otto cycle with air as the working fluid has a compression ratio of 8. The minimum and maximum temperatures in the cycle are 540 and 2400 R. Accounting for the variation of specific heats with temperature, determine (a) the amount of heat transferred to the air during the heat-addition process, (b) the thermal efficiency, and (c) the thermal efficiency of a Carnot cycle operating between the same temperature limits.
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An ideal Otto cycle with air as the working fluid has a compression ratio of 8, k=1.4. The
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c. the thermal efficiency of a Carnot cycle operating between the same
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An internal combustion engine is operating using a fuel as working fluid with a specific"capacity ratio of 1.5. The compression ratio and expansion ratio of the engine are 8 and 6, respectively. The engine operates in an Otto cycle where the temperatures of the working fluid before compression and before expansion are 30oC and 800oC,respectively. Calculate the efficiency of the Otto engine operating irreversibly if the efficiencies of compression and expansion are 0.8 and 0.9,respectively."
An ideal Otto cycle with air as the working fluid has a compression ratio of 8. The minimum and maximum temperature in the cycle are 300 and 1340 K. Accounting for the variation of specific heats with temperature, determine,
a.the amount of heat transferred to the air during the heat-addition process
b.the thermal efficiency, and
c.the thermal efficiency of a Carnot cycle operating between the same temperature limits
Answers: 567.72 kJ/kg, 53.0%, 77.6 %
Chapter 9 Solutions
Thermodynamics: An Engineering Approach
Ch. 9.12 - What are the air-standard assumptions?Ch. 9.12 - What is the difference between air-standard...Ch. 9.12 - How does the thermal efficiency of an ideal cycle,...Ch. 9.12 - What does the area enclosed by the cycle represent...Ch. 9.12 - Prob. 5PCh. 9.12 - Prob. 6PCh. 9.12 - Can the mean effective pressure of an automobile...Ch. 9.12 - Prob. 8PCh. 9.12 - What is the difference between spark-ignition and...Ch. 9.12 - Prob. 10P
Ch. 9.12 - Prob. 11PCh. 9.12 - Prob. 12PCh. 9.12 - Prob. 13PCh. 9.12 - Prob. 15PCh. 9.12 - Prob. 16PCh. 9.12 - Prob. 17PCh. 9.12 - Prob. 18PCh. 9.12 - Repeat Prob. 919 using helium as the working...Ch. 9.12 - Consider a Carnot cycle executed in a closed...Ch. 9.12 - Prob. 21PCh. 9.12 - Prob. 22PCh. 9.12 - What four processes make up the ideal Otto cycle?Ch. 9.12 - Are the processes that make up the Otto cycle...Ch. 9.12 - How do the efficiencies of the ideal Otto cycle...Ch. 9.12 - How does the thermal efficiency of an ideal Otto...Ch. 9.12 - Prob. 27PCh. 9.12 - Why are high compression ratios not used in...Ch. 9.12 - An ideal Otto cycle with a specified compression...Ch. 9.12 - Prob. 30PCh. 9.12 - Prob. 31PCh. 9.12 - Prob. 32PCh. 9.12 - An ideal Otto cycle has a compression ratio of 8....Ch. 9.12 - Prob. 35PCh. 9.12 - Prob. 36PCh. 9.12 - Prob. 37PCh. 9.12 - An ideal Otto cycle with air as the working fluid...Ch. 9.12 - Repeat Prob. 940E using argon as the working...Ch. 9.12 - Prob. 40PCh. 9.12 - Prob. 41PCh. 9.12 - Prob. 42PCh. 9.12 - Prob. 43PCh. 9.12 - Prob. 44PCh. 9.12 - Prob. 45PCh. 9.12 - Prob. 46PCh. 9.12 - Prob. 47PCh. 9.12 - Prob. 48PCh. 9.12 - Prob. 49PCh. 9.12 - Prob. 50PCh. 9.12 - Prob. 51PCh. 9.12 - Prob. 52PCh. 9.12 - Prob. 53PCh. 9.12 - Prob. 54PCh. 9.12 - Repeat Prob. 957, but replace the isentropic...Ch. 9.12 - Prob. 57PCh. 9.12 - Prob. 58PCh. 9.12 - Prob. 59PCh. 9.12 - The compression ratio of an ideal dual cycle is...Ch. 9.12 - Repeat Prob. 962 using constant specific heats at...Ch. 9.12 - Prob. 63PCh. 9.12 - An air-standard cycle, called the dual cycle, with...Ch. 9.12 - Prob. 65PCh. 9.12 - Prob. 66PCh. 9.12 - Consider the ideal Otto, Stirling, and Carnot...Ch. 9.12 - Consider the ideal Diesel, Ericsson, and Carnot...Ch. 9.12 - An ideal Ericsson engine using helium as the...Ch. 9.12 - An ideal Stirling engine using helium as the...Ch. 9.12 - Prob. 71PCh. 9.12 - Prob. 72PCh. 9.12 - Prob. 73PCh. 9.12 - Prob. 74PCh. 9.12 - Prob. 75PCh. 9.12 - For fixed maximum and minimum temperatures, what...Ch. 9.12 - What is the back work ratio? What are typical back...Ch. 9.12 - Why are the back work ratios relatively high in...Ch. 9.12 - How do the inefficiencies of the turbine and the...Ch. 9.12 - A simple ideal Brayton cycle with air as the...Ch. 9.12 - A gas-turbine power plant operates on the simple...Ch. 9.12 - Prob. 82PCh. 9.12 - Prob. 83PCh. 9.12 - Prob. 85PCh. 9.12 - 9–86 Consider a simple Brayton cycle using air as...Ch. 9.12 - 9–87 Air is used as the working fluid in a simple...Ch. 9.12 - Air is used as the working fluid in a simple ideal...Ch. 9.12 - An aircraft engine operates on a simple ideal...Ch. 9.12 - 9–91E A gas-turbine power plant operates on a...Ch. 9.12 - Prob. 92PCh. 9.12 - 9–93 A gas-turbine power plant operates on the...Ch. 9.12 - A gas-turbine power plant operates on a modified...Ch. 9.12 - Prob. 95PCh. 9.12 - Prob. 96PCh. 9.12 - Prob. 97PCh. 9.12 - Prob. 98PCh. 9.12 - 9–99 A gas turbine for an automobile is designed...Ch. 9.12 - Prob. 100PCh. 9.12 - A gas-turbine engine operates on the ideal Brayton...Ch. 9.12 - An ideal regenerator (T3 = T5) is added to a...Ch. 9.12 - Prob. 103PCh. 9.12 - Prob. 104PCh. 9.12 - Prob. 106PCh. 9.12 - A Brayton cycle with regeneration using air as the...Ch. 9.12 - Prob. 108PCh. 9.12 - Prob. 109PCh. 9.12 - Prob. 110PCh. 9.12 - Prob. 111PCh. 9.12 - Prob. 112PCh. 9.12 - Prob. 113PCh. 9.12 - Prob. 114PCh. 9.12 - Prob. 115PCh. 9.12 - A simple ideal Brayton cycle without regeneration...Ch. 9.12 - A simple ideal Brayton cycle is modified to...Ch. 9.12 - Prob. 118PCh. 9.12 - Consider a regenerative gas-turbine power plant...Ch. 9.12 - Repeat Prob. 9123 using argon as the working...Ch. 9.12 - Consider an ideal gas-turbine cycle with two...Ch. 9.12 - Repeat Prob. 9125, assuming an efficiency of 86...Ch. 9.12 - Prob. 123PCh. 9.12 - Prob. 124PCh. 9.12 - Prob. 126PCh. 9.12 - Prob. 127PCh. 9.12 - Prob. 128PCh. 9.12 - Prob. 129PCh. 9.12 - A turbojet is flying with a velocity of 900 ft/s...Ch. 9.12 - Prob. 131PCh. 9.12 - A pure jet engine propels an aircraft at 240 m/s...Ch. 9.12 - A turbojet aircraft is flying with a velocity of...Ch. 9.12 - Prob. 134PCh. 9.12 - Consider an aircraft powered by a turbojet engine...Ch. 9.12 - 9–137 Air at 7°C enters a turbojet engine at a...Ch. 9.12 - Prob. 138PCh. 9.12 - Prob. 139PCh. 9.12 - 9–140E Determine the exergy destruction associated...Ch. 9.12 - Prob. 141PCh. 9.12 - Prob. 142PCh. 9.12 - Prob. 143PCh. 9.12 - Prob. 144PCh. 9.12 - Prob. 146PCh. 9.12 - A gas-turbine power plant operates on the...Ch. 9.12 - Prob. 149PCh. 9.12 - Prob. 150RPCh. 9.12 - Prob. 151RPCh. 9.12 - Prob. 152RPCh. 9.12 - Prob. 153RPCh. 9.12 - Prob. 154RPCh. 9.12 - Prob. 155RPCh. 9.12 - Prob. 156RPCh. 9.12 - Prob. 157RPCh. 9.12 - Prob. 159RPCh. 9.12 - Prob. 161RPCh. 9.12 - Prob. 162RPCh. 9.12 - Prob. 163RPCh. 9.12 - Consider a simple ideal Brayton cycle with air as...Ch. 9.12 - Prob. 165RPCh. 9.12 - Helium is used as the working fluid in a Brayton...Ch. 9.12 - Consider an ideal gas-turbine cycle with one stage...Ch. 9.12 - Prob. 169RPCh. 9.12 - Prob. 170RPCh. 9.12 - Prob. 173RPCh. 9.12 - Prob. 174RPCh. 9.12 - Prob. 184FEPCh. 9.12 - For specified limits for the maximum and minimum...Ch. 9.12 - Prob. 186FEPCh. 9.12 - Prob. 187FEPCh. 9.12 - Helium gas in an ideal Otto cycle is compressed...Ch. 9.12 - Prob. 189FEPCh. 9.12 - Prob. 190FEPCh. 9.12 - Consider an ideal Brayton cycle executed between...Ch. 9.12 - An ideal Brayton cycle has a net work output of...Ch. 9.12 - In an ideal Brayton cycle, air is compressed from...Ch. 9.12 - In an ideal Brayton cycle with regeneration, argon...Ch. 9.12 - In an ideal Brayton cycle with regeneration, air...Ch. 9.12 - Consider a gas turbine that has a pressure ratio...Ch. 9.12 - An ideal gas turbine cycle with many stages of...Ch. 9.12 - Prob. 198FEP
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