Thermodynamics: An Engineering Approach
9th Edition
ISBN: 9781260048766
Author: CENGEL
Publisher: MCG
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Chapter 9.12, Problem 117P
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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2. A freezer of 20 TR capacity has evaporator and condenser temperatures of 30°C and
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[Ans. 1.57 bar; 14.9% ; 4560 kW)
loss in combustion.
on (sat vapor) o, Py 0.14MPa @Ty Rizia (®) tig- 1340 =7 © ¥y =1 om/kg) (@ Ta= (©) Miomy ) Qo= @) BSvura =2 Comdenser) An adiabatic compressor works with R-134a as working fluid and 0.15 KW. The refrigerant enters compressor as saturated vapor at 0.14MPa. The refrigerant leaves compressor at 70°C and 1.2MPa and then enters condenser 10 be cooled at which pressure remains constant and leaves condenser at 40°C. If the surrounding temperature is 30° Find: (a) initial temperature (T1). (b) mass flow rate of R-134a, (¢) volumetric rate of R-1342 at entrance. of compressor ( ¥;). (@) T, . (¢) compressor efficiency, (1) rate of heat Tosses from condenser, and (g) fotal entropy generation in condenser and also show if the process is possible or not.
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 - Prob. 3PCh. 9.12 - How does the thermal efficiency of an ideal cycle,...Ch. 9.12 - How are the combustion and exhaust processes...Ch. 9.12 - What does the area enclosed by the cycle represent...Ch. 9.12 - Prob. 7PCh. 9.12 - Can the mean effective pressure of an automobile...Ch. 9.12 - What is the difference between spark-ignition and...Ch. 9.12 - Prob. 10P
Ch. 9.12 - Prob. 11PCh. 9.12 - Can any ideal gas power cycle have a thermal...Ch. 9.12 - Prob. 13PCh. 9.12 - Prob. 14PCh. 9.12 - Prob. 15PCh. 9.12 - Prob. 16PCh. 9.12 - Prob. 17PCh. 9.12 - Prob. 18PCh. 9.12 - Prob. 19PCh. 9.12 - Repeat Prob. 919 using helium as the working...Ch. 9.12 - The thermal energy reservoirs of an ideal gas...Ch. 9.12 - Consider a Carnot cycle executed in a closed...Ch. 9.12 - Consider a Carnot cycle executed in a closed...Ch. 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 - 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 - Determine the mean effective pressure of an ideal...Ch. 9.12 - Reconsider Prob. 932E. Determine the rate of heat...Ch. 9.12 - An ideal Otto cycle has a compression ratio of 8....Ch. 9.12 - Prob. 36PCh. 9.12 - A spark-ignition engine has a compression ratio of...Ch. 9.12 - An ideal Otto cycle has a compression ratio of 7....Ch. 9.12 - Prob. 39PCh. 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 - Someone has suggested that the air-standard Otto...Ch. 9.12 - Repeat Prob. 942 when isentropic processes are...Ch. 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 - Prob. 55PCh. 9.12 - Prob. 56PCh. 9.12 - Prob. 57PCh. 9.12 - Repeat Prob. 957, but replace the isentropic...Ch. 9.12 - Prob. 60PCh. 9.12 - Prob. 61PCh. 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. 65PCh. 9.12 - Prob. 66PCh. 9.12 - Prob. 67PCh. 9.12 - An air-standard cycle, called the dual cycle, with...Ch. 9.12 - Prob. 69PCh. 9.12 - Prob. 70PCh. 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. 75PCh. 9.12 - Prob. 76PCh. 9.12 - Prob. 77PCh. 9.12 - Prob. 78PCh. 9.12 - Prob. 79PCh. 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 stationary gas-turbine power plant operates on a...Ch. 9.12 - A gas-turbine power plant operates on the simple...Ch. 9.12 - Prob. 87PCh. 9.12 - Prob. 88PCh. 9.12 - Repeat Prob. 988 when the isentropic efficiency of...Ch. 9.12 - Repeat Prob. 988 when the isentropic efficiency of...Ch. 9.12 - Repeat Prob. 988 when the isentropic efficiencies...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 - Repeat Prob. 993 for a pressure ratio of 15.Ch. 9.12 - A gas-turbine power plant operates on the simple...Ch. 9.12 - A simple ideal Brayton cycle uses argon as the...Ch. 9.12 - A gas-turbine power plant operates on a modified...Ch. 9.12 - A gas-turbine power plant operating on the simple...Ch. 9.12 - Prob. 99PCh. 9.12 - Prob. 100PCh. 9.12 - Prob. 101PCh. 9.12 - Prob. 102PCh. 9.12 - Prob. 103PCh. 9.12 - Prob. 104PCh. 9.12 - A gas turbine for an automobile is designed with a...Ch. 9.12 - Rework Prob. 9105 when the compressor isentropic...Ch. 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. 109PCh. 9.12 - Prob. 111PCh. 9.12 - A Brayton cycle with regeneration using air as the...Ch. 9.12 - Prob. 113PCh. 9.12 - Prob. 114PCh. 9.12 - Prob. 115PCh. 9.12 - Prob. 116PCh. 9.12 - Prob. 117PCh. 9.12 - Prob. 118PCh. 9.12 - Prob. 119PCh. 9.12 - Prob. 120PCh. 9.12 - A simple ideal Brayton cycle without regeneration...Ch. 9.12 - A simple ideal Brayton cycle is modified to...Ch. 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 - A gas turbine operates with a regenerator and two...Ch. 9.12 - Prob. 128PCh. 9.12 - Prob. 129PCh. 9.12 - Prob. 130PCh. 9.12 - Prob. 131PCh. 9.12 - Air at 7C enters a turbojet engine at a rate of 16...Ch. 9.12 - Prob. 133PCh. 9.12 - A turbojet is flying with a velocity of 900 ft/s...Ch. 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. 137PCh. 9.12 - Prob. 138PCh. 9.12 - Reconsider Prob. 9138E. How much change would...Ch. 9.12 - Consider an aircraft powered by a turbojet engine...Ch. 9.12 - An ideal Otto cycle has a compression ratio of 8....Ch. 9.12 - An air-standard Diesel cycle has a compression...Ch. 9.12 - Prob. 144PCh. 9.12 - Prob. 145PCh. 9.12 - Prob. 146PCh. 9.12 - Prob. 147PCh. 9.12 - A Brayton cycle with regeneration using air as the...Ch. 9.12 - Prob. 150PCh. 9.12 - A gas turbine operates with a regenerator and two...Ch. 9.12 - A gas-turbine power plant operates on the...Ch. 9.12 - Prob. 153PCh. 9.12 - An air-standard cycle with variable specific heats...Ch. 9.12 - Prob. 155RPCh. 9.12 - Prob. 156RPCh. 9.12 - Prob. 157RPCh. 9.12 - Prob. 158RPCh. 9.12 - Prob. 159RPCh. 9.12 - Prob. 160RPCh. 9.12 - Prob. 161RPCh. 9.12 - Consider an engine operating on the ideal Diesel...Ch. 9.12 - Repeat Prob. 9162 using argon as the working...Ch. 9.12 - Prob. 164RPCh. 9.12 - Prob. 165RPCh. 9.12 - Prob. 166RPCh. 9.12 - Prob. 167RPCh. 9.12 - Consider an ideal Stirling cycle using air as the...Ch. 9.12 - Prob. 169RPCh. 9.12 - Consider a simple ideal Brayton cycle with air as...Ch. 9.12 - Prob. 171RPCh. 9.12 - A Brayton cycle with a pressure ratio of 15...Ch. 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. 176RPCh. 9.12 - Prob. 177RPCh. 9.12 - Prob. 180RPCh. 9.12 - Prob. 181RPCh. 9.12 - Prob. 182RPCh. 9.12 - For specified limits for the maximum and minimum...Ch. 9.12 - A Carnot cycle operates between the temperature...Ch. 9.12 - Prob. 194FEPCh. 9.12 - Prob. 195FEPCh. 9.12 - Helium gas in an ideal Otto cycle is compressed...Ch. 9.12 - Prob. 197FEPCh. 9.12 - Prob. 198FEPCh. 9.12 - In an ideal Brayton cycle, air is compressed from...Ch. 9.12 - In an ideal Brayton cycle, air is compressed from...Ch. 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 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...
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