Thermodynamics: An Engineering Approach ( 9th International Edition ) ISBN:9781260092684
9th Edition
ISBN: 9781260048667
Author: Yunus A. Cengel Dr.; Michael A. Boles
Publisher: McGraw-Hill Education
expand_more
expand_more
format_list_bulleted
Textbook Question
Chapter 7.13, Problem 222RP
Consider a three-stage isentropic compressor with two intercoolers that cool the gas to the initial temperature between the stages. Determine the two intermediate pressures (Px and Py) in terms of inlet and exit pressures (P1 and P2) that will minimize the work input to the compressor.
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solutionStudents have asked these similar questions
An ideal compressor pressurizes air at 100 kPa and 300 K to 1000 kPa. If the compressor has a mass flow rate of 0.042 kg/s, assuming variable specific heats what is the final temperature of the air leaving the compressor and how much power does the compressor use?
Refrigerant 22 at a pressure of 1500 kPa leaves the condenser and rises vertically11 m to the expansion valve. The pressure drop due to friction in the liquid line is21 kPa. In order to have no vapor in the refrigerant entering the expansion valve,what is the maximum allowable temperature at that point?
A commercial airliner is flying at an altitude where the temperature and pressure of
the air are -50°C and 26.5 kPa. An engine-driven compressor will take this air at
T₁ = -50°C, P₁ = 26.5 kPa and compress it to P₂ = P₂ = 85.0 kPa to pressurize the
cabin. The air will be very hot when it exits the compressor, so a heat exchanger will be
used to cool the air to T, = 20°C before it enters the cabin. Cold air at T₁ = -50°C will
be used in the heat exchanger to cool the cabin air, and this air will exit the heat
exchanger at T = 20°C (this air will be used to heat the cargo bay). The mass flow rate
of the air delivered to the cabin is 0.80 kg/s and the compressor efficiency is 75%.
Model the air as an ideal gas having variable specific heat, using values from Cengel's
tables posted on Canvas.
a) Find the actual temperature of the air exiting the compressor and the power input
to the compressor (answers: 67.9°C and 94.7 kW).
b) Find the rate of heat transfer in the heat exchanger and the…
Chapter 7 Solutions
Thermodynamics: An Engineering Approach ( 9th International Edition ) ISBN:9781260092684
Ch. 7.13 - Does a cycle for which Q 0 violate the Clausius...Ch. 7.13 - Does the cyclic integral of heat have to be zero...Ch. 7.13 - Is a quantity whose cyclic integral is zero...Ch. 7.13 - Prob. 4PCh. 7.13 - Prob. 5PCh. 7.13 - How do the values of the integral 12Q/T compare...Ch. 7.13 - Prob. 7PCh. 7.13 - The entropy of a hot baked potato decreases as it...Ch. 7.13 - When a system is adiabatic, what can be said about...Ch. 7.13 - Prob. 10P
Ch. 7.13 - A pistoncylinder device contains helium gas....Ch. 7.13 - A pistoncylinder device contains nitrogen gas....Ch. 7.13 - A pistoncylinder device contains superheated...Ch. 7.13 - The entropy of steam will (increase, decrease,...Ch. 7.13 - During a heat transfer process, the entropy of a...Ch. 7.13 - Steam is accelerated as it flows through an actual...Ch. 7.13 - Heat is transferred at a rate of 2 kW from a hot...Ch. 7.13 - A completely reversible air conditioner provides...Ch. 7.13 - Heat in the amount of 100 kJ is transferred...Ch. 7.13 - In Prob. 719, assume that the heat is transferred...Ch. 7.13 - During the isothermal heat addition process of a...Ch. 7.13 - Prob. 22PCh. 7.13 - During the isothermal heat rejection process of a...Ch. 7.13 - Air is compressed by a 40-kW compressor from P1 to...Ch. 7.13 - Refrigerant-134a enters the coils of the...Ch. 7.13 - A rigid tank contains an ideal gas at 40C that is...Ch. 7.13 - A rigid vessel is filled with a fluid from a...Ch. 7.13 - A rigid vessel filled with a fluid is allowed to...Ch. 7.13 - Prob. 29PCh. 7.13 - One lbm of R-134a is expanded isentropically in a...Ch. 7.13 - Two lbm of water at 300 psia fill a weighted...Ch. 7.13 - A well-insulated rigid tank contains 3 kg of a...Ch. 7.13 - Using the relation ds = (Q/T)int rev for the...Ch. 7.13 - The radiator of a steam heating system has a...Ch. 7.13 - A rigid tank is divided into two equal parts by a...Ch. 7.13 - Prob. 36PCh. 7.13 - An insulated pistoncylinder device contains 5 L of...Ch. 7.13 - Onekg of R-134a initially at 600 kPa and 25C...Ch. 7.13 - Refrigerant-134a is expanded isentropically from...Ch. 7.13 - Refrigerant-134a at 320 kPa and 40C undergoes an...Ch. 7.13 - A rigid tank contains 5 kg of saturated vapor...Ch. 7.13 - A 0.5-m3 rigid tank contains refrigerant-134a...Ch. 7.13 - Steam enters a steady-flow adiabatic nozzle with a...Ch. 7.13 - Steam enters an adiabatic diffuser at 150 kPa and...Ch. 7.13 - R-134a vapor enters into a turbine at 250 psia and...Ch. 7.13 - Refrigerant-134a enters an adiabatic compressor as...Ch. 7.13 - The compressor in a refrigerator compresses...Ch. 7.13 - An isentropic steam turbine processes 2 kg/s of...Ch. 7.13 - Prob. 52PCh. 7.13 - Twokg of saturated water vapor at 600 kPa are...Ch. 7.13 - A pistoncylinder device contains 5 kg of steam at...Ch. 7.13 - Prob. 55PCh. 7.13 - In Prob. 755, the water is stirred at the same...Ch. 7.13 - Prob. 57PCh. 7.13 - Prob. 58PCh. 7.13 - Determine the total heat transfer for the...Ch. 7.13 - Calculate the heat transfer, in kJ/kg. for the...Ch. 7.13 - Prob. 61PCh. 7.13 - An adiabatic pump is to be used to compress...Ch. 7.13 - Prob. 63PCh. 7.13 - Prob. 64PCh. 7.13 - A 30-kg aluminum block initially at 140C is...Ch. 7.13 - A 50-kg copper block initially at 140C is dropped...Ch. 7.13 - A 30-kg iron block and a 40-kg copper block, both...Ch. 7.13 - Prob. 69PCh. 7.13 - Prob. 70PCh. 7.13 - Can the entropy of an ideal gas change during an...Ch. 7.13 - An ideal gas undergoes a process between two...Ch. 7.13 - Prob. 73PCh. 7.13 - Air is expanded from 200 psia and 500F to 100 psia...Ch. 7.13 - Prob. 75PCh. 7.13 - Air is expanded isentropically from 100 psia and...Ch. 7.13 - Which of the two gaseshelium or nitrogenhas the...Ch. 7.13 - Which of the two gasesneon or airhas the lower...Ch. 7.13 - A 1.5-m3 insulated rigid tank contains 2.7 kg of...Ch. 7.13 - An insulated pistoncylinder device initially...Ch. 7.13 - A pistoncylinder device contains 0.75 kg of...Ch. 7.13 - A mass of 25 lbm of helium undergoes a process...Ch. 7.13 - One kg of air at 200 kPa and 127C is contained in...Ch. 7.13 - An insulated rigid tank is divided into two equal...Ch. 7.13 - Air at 27C and 100 kPa is contained in a...Ch. 7.13 - Air at 3.5 MPa and 500C is expanded in an...Ch. 7.13 - Air is compressed in a pistoncylinder device from...Ch. 7.13 - Helium gas is compressed from 90 kPa and 30C to...Ch. 7.13 - Nitrogen at 120 kPa and 30C is compressed to 600...Ch. 7.13 - Five kg of air at 427C and 600 kPa are contained...Ch. 7.13 - Prob. 92PCh. 7.13 - Prob. 93PCh. 7.13 - Prob. 94PCh. 7.13 - The well-insulated container shown in Fig. P 795E...Ch. 7.13 - An insulated rigid tank contains 4 kg of argon gas...Ch. 7.13 - Prob. 97PCh. 7.13 - Prob. 98PCh. 7.13 - Prob. 99PCh. 7.13 - It is well known that the power consumed by a...Ch. 7.13 - Calculate the work produced, in kJ/kg, for the...Ch. 7.13 - Prob. 102PCh. 7.13 - Prob. 103PCh. 7.13 - Saturated water vapor at 150C is compressed in a...Ch. 7.13 - Liquid water at 120 kPa enters a 7-kW pump where...Ch. 7.13 - Water enters the pump of a steam power plant as...Ch. 7.13 - Consider a steam power plant that operates between...Ch. 7.13 - Saturated refrigerant-134a vapor at 15 psia is...Ch. 7.13 - Helium gas is compressed from 16 psia and 85F to...Ch. 7.13 - Nitrogen gas is compressed from 80 kPa and 27C to...Ch. 7.13 - Describe the ideal process for an (a) adiabatic...Ch. 7.13 - Is the isentropic process a suitable model for...Ch. 7.13 - On a T-s diagram, does the actual exit state...Ch. 7.13 - Argon gas enters an adiabatic turbine at 800C and...Ch. 7.13 - Steam at 100 psia and 650F is expanded...Ch. 7.13 - Combustion gases enter an adiabatic gas turbine at...Ch. 7.13 - Steam at 4 MPa and 350C is expanded in an...Ch. 7.13 - Prob. 120PCh. 7.13 - Prob. 121PCh. 7.13 - Refrigerant-134a enters an adiabatic compressor as...Ch. 7.13 - The adiabatic compressor of a refrigeration system...Ch. 7.13 - Prob. 125PCh. 7.13 - Argon gas enters an adiabatic compressor at 14...Ch. 7.13 - Prob. 127PCh. 7.13 - Air enters an adiabatic nozzle at 45 psia and 940F...Ch. 7.13 - An adiabatic diffuser at the inlet of a jet engine...Ch. 7.13 - Hot combustion gases enter the nozzle of a...Ch. 7.13 - The exhaust nozzle of a jet engine expands air at...Ch. 7.13 - Prob. 133PCh. 7.13 - Refrigerant-134a is expanded adiabatically from...Ch. 7.13 - A frictionless pistoncylinder device contains...Ch. 7.13 - Prob. 136PCh. 7.13 - Steam enters an adiabatic turbine steadily at 7...Ch. 7.13 - Prob. 138PCh. 7.13 - Oxygen enters an insulated 12-cm-diameter pipe...Ch. 7.13 - Water at 20 psia and 50F enters a mixing chamber...Ch. 7.13 - Prob. 141PCh. 7.13 - Prob. 142PCh. 7.13 - In a dairy plant, milk at 4C is pasteurized...Ch. 7.13 - Steam is to be condensed in the condenser of a...Ch. 7.13 - An ordinary egg can be approximated as a...Ch. 7.13 - Prob. 146PCh. 7.13 - In a production facility, 1.2-in-thick, 2-ft 2-ft...Ch. 7.13 - Prob. 148PCh. 7.13 - Prob. 149PCh. 7.13 - Prob. 150PCh. 7.13 - Prob. 151PCh. 7.13 - Prob. 152PCh. 7.13 - Prob. 153PCh. 7.13 - Liquid water at 200 kPa and 15C is heated in a...Ch. 7.13 - Prob. 155PCh. 7.13 - Prob. 157PCh. 7.13 - Prob. 158PCh. 7.13 - Prob. 159PCh. 7.13 - Prob. 160PCh. 7.13 - The compressed-air requirements of a plant are met...Ch. 7.13 - Prob. 162PCh. 7.13 - The space heating of a facility is accomplished by...Ch. 7.13 - Prob. 164PCh. 7.13 - Prob. 165PCh. 7.13 - Prob. 166PCh. 7.13 - Prob. 167RPCh. 7.13 - A refrigerator with a coefficient of performance...Ch. 7.13 - What is the minimum internal energy that steam can...Ch. 7.13 - Prob. 170RPCh. 7.13 - What is the maximum volume that 3 kg of oxygen at...Ch. 7.13 - A 100-lbm block of a solid material whose specific...Ch. 7.13 - Prob. 173RPCh. 7.13 - A pistoncylinder device initially contains 15 ft3...Ch. 7.13 - A pistoncylinder device contains steam that...Ch. 7.13 - Prob. 176RPCh. 7.13 - Prob. 177RPCh. 7.13 - Prob. 178RPCh. 7.13 - A 0.8-m3 rigid tank contains carbon dioxide (CO2)...Ch. 7.13 - Air enters the evaporator section of a window air...Ch. 7.13 - Prob. 181RPCh. 7.13 - Prob. 182RPCh. 7.13 - Prob. 183RPCh. 7.13 - Prob. 184RPCh. 7.13 - Helium gas is throttled steadily from 400 kPa and...Ch. 7.13 - Determine the work input and entropy generation...Ch. 7.13 - Prob. 187RPCh. 7.13 - Reconsider Prob. 7187. Determine the change in the...Ch. 7.13 - Prob. 189RPCh. 7.13 - Air enters a two-stage compressor at 100 kPa and...Ch. 7.13 - Three kg of helium gas at 100 kPa and 27C are...Ch. 7.13 - Steam at 6 MPa and 500C enters a two-stage...Ch. 7.13 - Prob. 193RPCh. 7.13 - Prob. 194RPCh. 7.13 - Refrigerant-134a enters a compressor as a...Ch. 7.13 - Prob. 196RPCh. 7.13 - Prob. 197RPCh. 7.13 - Prob. 198RPCh. 7.13 - Prob. 199RPCh. 7.13 - Prob. 200RPCh. 7.13 - Prob. 201RPCh. 7.13 - Prob. 202RPCh. 7.13 - Prob. 203RPCh. 7.13 - Prob. 204RPCh. 7.13 - Prob. 205RPCh. 7.13 - Prob. 206RPCh. 7.13 - Prob. 207RPCh. 7.13 - Prob. 208RPCh. 7.13 - (a) Water flows through a shower head steadily at...Ch. 7.13 - Prob. 211RPCh. 7.13 - Prob. 212RPCh. 7.13 - Prob. 213RPCh. 7.13 - Consider the turbocharger of an internal...Ch. 7.13 - Prob. 215RPCh. 7.13 - Prob. 216RPCh. 7.13 - A 5-ft3 rigid tank initially contains...Ch. 7.13 - Prob. 218RPCh. 7.13 - Show that the difference between the reversible...Ch. 7.13 - Demonstrate the validity of the Clausius...Ch. 7.13 - Consider two bodies of identical mass m and...Ch. 7.13 - Consider a three-stage isentropic compressor with...Ch. 7.13 - Prob. 223RPCh. 7.13 - Prob. 224RPCh. 7.13 - Prob. 225RPCh. 7.13 - The polytropic or small stage efficiency of a...Ch. 7.13 - Steam is condensed at a constant temperature of...Ch. 7.13 - Steam is compressed from 6 MPa and 300C to 10 MPa...Ch. 7.13 - An apple with a mass of 0.12 kg and average...Ch. 7.13 - A pistoncylinder device contains 5 kg of saturated...Ch. 7.13 - Argon gas expands in an adiabatic turbine from 3...Ch. 7.13 - A unit mass of a substance undergoes an...Ch. 7.13 - A unit mass of an ideal gas at temperature T...Ch. 7.13 - Heat is lost through a plane wall steadily at a...Ch. 7.13 - Air is compressed steadily and adiabatically from...Ch. 7.13 - Argon gas expands in an adiabatic turbine steadily...Ch. 7.13 - Water enters a pump steadily at 100 kPa at a rate...Ch. 7.13 - Air is to be compressed steadily and...Ch. 7.13 - Helium gas enters an adiabatic nozzle steadily at...Ch. 7.13 - Combustion gases with a specific heat ratio of 1.3...Ch. 7.13 - Steam enters an adiabatic turbine steadily at 400C...Ch. 7.13 - Liquid water enters an adiabatic piping system at...Ch. 7.13 - Liquid water is to be compressed by a pump whose...Ch. 7.13 - Steam enters an adiabatic turbine at 8 MPa and...Ch. 7.13 - Helium gas is compressed steadily from 90 kPa and...Ch. 7.13 - Helium gas is compressed from 1 atm and 25C to a...
Knowledge Booster
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, mechanical-engineering and related others by exploring similar questions and additional content below.Similar questions
- Air with mass flow rate of 1 kg/s enters the first stage of a compressor at 100 kPa and 300 K and exit the second stage of the compressor at 2677 kPa. If the compressed air outgoing from the first stage of the compressor passes through an intercooler, then enters the second stage of the compressor at temperature 353 K. What is the indicated isothermal efficiency for the compressor assuming ideal compression process with polytropica index n = 1.3 for both stages, no pressure loss in the intercooler, and the pressure ratio across the first and the second stage of the compressor are equal?arrow_forwardIn Otto Cycle, air at 18oC is first compressed to one- eight of its original volume. If the heat input to the cycle is 460 KJ/Kg of air, determine The temperature of the remaining points in the cycle. The ratio of the maximum and minimum pressure in the cycle.arrow_forwardIn a refrigerator the pressure in the evaporator us 2.72 kg/cm sq. and the refrigerant entry is 0.12 dry while at the exit 0.91 dry. During the compression, the work done per kg is 17,033 kg-m/kg. Calculate the COP. The rate of refrigerant circulation is 5.64 kg/min. The given latent heat and specific volume at 2.72 kg/cm sq are 320 kcal/kg ang 0.436 cu m/kg.arrow_forward
- A commercial airliner is flying at an altitude where the temperature and pressure of the air are -50°C and 26.5 kPa. An engine-driven compressor will take this air at T= -50°C, P₁ = 26.5 kPa and compress it to P₂ = P₂ = 85.0 kPa to pressurize the cabin. The air will be very hot when it exits the compressor, so a heat exchanger will be used to cool the air to T, = 20°C before it enters the cabin. Cold air at T₁ = -50°C will be used in the heat exchanger to cool the cabin air, and this air will exit the heat exchanger at T = 20°C (this air will be used to heat the cargo bay). The mass flow rate of the air delivered to the cabin is 0.80 kg/s and the compressor efficiency is 75%. Model the air as an ideal gas having constant specific heat, using 300 K values from Cengel's tables posted on Canvas. a) Find the actual temperature of the air exiting the compressor and the power input to the compressor (answers: 67.6°C and 94.5 kW). b) Find the rate of heat transfer in the heat exchanger and…arrow_forwardIn an ammonia refrigerator , the pressure in the evaporator is 267. 58 KPa and the ammonia at is 0.14 dry while at the exit is 0.86 dry . During compression the work done per kg of ammonia is 20 ,000 kg .m . Calculate volume of the vapor entering the compressor per minute if the rate of ammonia circulation is 6.54 kg. The compressor has a volumetric efficiency of 90% and it runs at 150 rpm .The ratio of stroke to bore is 1 .Latent enthalpy of ammonia at based on its evaporating pressure is 320 Kcal per kg and its latent specific volume of ammonia based on its evaporating pressure is 0.436 m3 per kg .Specific volume of ammonia WITH PH DIAGRAMarrow_forwardRefrigerant-134a is throttled from the saturated liquid state at 800 kPa to a temperature of -20°C. a. Determine the pressure of the refrigerant at the final state. b. Determine the quality of the refrigerant at the final state.arrow_forward
- Problem # 1 An isolated cylinder-piston system is connected to a supply line through a valve. The supply line conditions are P= 600 kPa and T= 100 C. Initially, the cylinder contains 0.1 m of air at 150 kPa and 30 C. when the valve is opened, air enters the cylinder and the piston is slowly pushed upwards until the final volume is twice the initial volume. If the specific heats are taken as constant, determine: a. Final temperature in the cylinder b. Mass of air that entered the cylinder.arrow_forwardA schematic of a steam power plant is shown in the figure. The boiler volume is 50 liter and contains 90% liquid and 10% steam at 100kPa. The boiler is heated and when the pressure at the boiler reaches 700kPa, the pressure valve is switched on to maintain a constant pressure of 700kPa. At this pressure, saturated steam moves to an adiabatic turbine. The saturated steam leaves the turbine at 100kPa to the atmosphere. When all the liquid at the boiler evaporator, the heating stops automatically. Calculate the amount of work obtained by the turbine and the amount of heat to be provided to the boiler over one cycle.arrow_forwardAir at the rate of 25 kg/min is compressed in a centrifugal compressor from 1 bar to 2 bar. The temperature increases from 15°C to 105°C during compression. Determine actual and minimum power required to run the compressor. The surrounding air temperature is 15°C. Neglect the changes in K.E. and P.E.arrow_forward
- Air (R = 0.3074 psia.cf/lbm.R) is compressed from 14.7 psia and 60°F to a pressure of 150 psia while heat loss rate during the steady compression is 10 Btu/lbm. The volume flow rate of the air at the inlet is 5,000 ft'/min and the power input to the compressor is 700 hp. Determine the temperature at the compressor exit in °F. (1hp = 0.7068 Btu/s) AIR %3D 10 Bru Ibmarrow_forward2. 26 tons of ice from and at 0°C is produced per day in an ammonia refrigerator. The temperature range in the compressor is from 26°C to -15°C. The vapour is dry and saturated at the end of compression. Assuming actual COP is 62% of theoretical, calculate the power required to drive the compressor. Take latent heat of ice 335 kJ/kg.arrow_forwardthe compressor and expander have to be assumed to have an actual efficiency that is less than ideal. Suppose the air cooled to room temperature before expanding it. Considering that the adiabatic efficiency of the compressor is 78% and the efficiency of the expander (a turbine) is 82%, how efficient will the system be as an energy store?arrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
- Elements Of ElectromagneticsMechanical EngineeringISBN:9780190698614Author:Sadiku, Matthew N. O.Publisher:Oxford University PressMechanics of Materials (10th Edition)Mechanical EngineeringISBN:9780134319650Author:Russell C. HibbelerPublisher:PEARSONThermodynamics: An Engineering ApproachMechanical EngineeringISBN:9781259822674Author:Yunus A. Cengel Dr., Michael A. BolesPublisher:McGraw-Hill Education
- Control Systems EngineeringMechanical EngineeringISBN:9781118170519Author:Norman S. NisePublisher:WILEYMechanics of Materials (MindTap Course List)Mechanical EngineeringISBN:9781337093347Author:Barry J. Goodno, James M. GerePublisher:Cengage LearningEngineering Mechanics: StaticsMechanical EngineeringISBN:9781118807330Author:James L. Meriam, L. G. Kraige, J. N. BoltonPublisher:WILEY
Elements Of Electromagnetics
Mechanical Engineering
ISBN:9780190698614
Author:Sadiku, Matthew N. O.
Publisher:Oxford University Press
Mechanics of Materials (10th Edition)
Mechanical Engineering
ISBN:9780134319650
Author:Russell C. Hibbeler
Publisher:PEARSON
Thermodynamics: An Engineering Approach
Mechanical Engineering
ISBN:9781259822674
Author:Yunus A. Cengel Dr., Michael A. Boles
Publisher:McGraw-Hill Education
Control Systems Engineering
Mechanical Engineering
ISBN:9781118170519
Author:Norman S. Nise
Publisher:WILEY
Mechanics of Materials (MindTap Course List)
Mechanical Engineering
ISBN:9781337093347
Author:Barry J. Goodno, James M. Gere
Publisher:Cengage Learning
Engineering Mechanics: Statics
Mechanical Engineering
ISBN:9781118807330
Author:James L. Meriam, L. G. Kraige, J. N. Bolton
Publisher:WILEY
Power Plant Explained | Working Principles; Author: RealPars;https://www.youtube.com/watch?v=HGVDu1z5YQ8;License: Standard YouTube License, CC-BY