EBK THERMODYNAMICS: AN ENGINEERING APPR
8th Edition
ISBN: 9780100257054
Author: CENGEL
Publisher: YUZU
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Chapter 9.12, Problem 113P
To determine
State the reason why the multistage compression reduces the compression work as a result of inter-cooling and the multistage expansion increases the turbine work as a result of reheating for a specified pressure ratio.
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For a specified pressure ratio, why does multistage compression with intercooling decrease the compressor work, and multistage expansion with reheating increase the turbine work?
2. A freezer of 20 TR capacity has evaporator and condenser temperatures of 30°C and
25°C respectively. The refrigerant R-12 is sub-cooled by 4°C before it enters the expansion
valve and is superheated by 5°C before leaving the evaporator. The compression is
isentropic and the valve throttling and clearance are to be neglected. If a six-cylinder, single
acting compressor with stroke equal to bore running at 1000 r.p.m. is used, determine:
A- C.O.P. of the refrigerating system,
B- Mass of refrigerant to be circulated per min,
C- Theoretical piston displacement per minute and
D- Theoretical bore and stroke of the compressor.
28. In a marine gas turbine unit a high-pressure stage turbine drives the compressor, and a low-pressure stage
turbine drives the propeller through suitable gearing. The overall pressure ratio is 4: 1, and the maximum
temperature is 650°C. The isentropic efficiencies of the compressor, H.P. turbine, and L.P. turbine are 0.8,
0.83, and 0.85 respectively, and the mechanical efficiency of both shafts is 98%. Calculate the pressure
between turbine stages when the air intake conditions are 1.01 bar and 25°C. Calculate also the thermal
efficiency and the shaft power when the mass flow is 60 kg/s. Neglect kinetic energy changes, and pressure
[Ans. 1.57 bar; 14.9% ; 4560 kW)
loss in combustion.
Chapter 9 Solutions
EBK THERMODYNAMICS: AN ENGINEERING APPR
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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