New Semester Started Get 50% OFF Study Help! --h --m --s Claim Now

Question Answers

Textbooks

Find textbooks, questions and answers

Oops, something went wrong!

Change your search query and then try again

Result Not Found

Books FREE
Study Help
Tutors
AI Study Planner NEW
Sell Books

Search
Sign In
Register

study help
engineering
mechanical engineering

Fundamentals of Thermodynamics 6th edition Richard E. Sonntag, Claus Borgnakke, Gordon J. Van Wylen - Solutions

How are the combustion and exhaust processes modeled under the air-standard assumptions?
What are the air-standard assumptions?
What is the difference between the clearance volume and the displacement volume of reciprocating engines?
Define the compression ratio for reciprocating engines.
How is the mean effective pressure for reciprocating engines defined?
The single-stage compression process of an ideal Brayton cycle without regeneration is replaced by a multistage compression process with intercooling between the same pressure limits. As a result of this modification, (a) Does the compressor work increase, decrease, or remain the same? (b) Does
As a car gets older, will its compression ratio change? How about the mean effective pressure?
What is the difference between spark-ignition and compression-ignition engines?
Define the following terms related to reciprocating engines: stroke, bore, top dead center, and clearance volume.
An air-standard cycle with variable specific heats is executed in a closed system and is composed of the following four processes: 1-2 Isentropic compression from 100 kPa and 27°C to 800 kPa 2-3 v = constant heat addition to 1800 K 3-4 Isentropic expansion to 100 kPa 4-1 P = constant heat
Reconsider Problem 9–14. Using EES (or other) software, study the effect of varying the temperature after the constant-volume heat addition from 1500 K to 2500 K. Plot the net work output and thermal efficiency as a function of the maximum temperature of the cycle. Plot the T-s and P-v diagrams
An air-standard cycle is executed in a closed system and is composed of the following four processes: 1-2 Isentropic compression from 100 kPa and 27°C to 1 MPa 2-3 P = constant heat addition in amount of 2800 kJ/kg 3-4 v = constant heat rejection to 100 kPa 4-1 P = constant heat rejection to
An air-standard cycle with variable specific heats is executed in a closed system and is composed of the following four processes: 1-2 v = constant heat addition from 14.7 psia and 80°F in the amount of 300 Btu/lbm 2-3 P = constant heat addition to 3200 R 3-4 Isentropic expansion to 14.7
Repeat Problem 9–17E using constant specific heats at room temperature.
An air-standard cycle is executed in a closed system with 0.004 kg of air and consists of the following three processes: 1-2 Isentropic compression from 100 kPa and 27°C to 1 MPa 2-3 P = constant heat addition in the amount of 2.76 kJ 3-1 P = c1v + c2 heat rejection to initial state (c1 and c2
An air-standard cycle with variable specific heats is executed in a closed system with 0.003 kg of air and consists of the following three processes: 1-2 v = constant heat addition from 95 kPa and 17°C to 380 kPa 2-3 Isentropic expansion to 95 kPa 3-1 P = constant heat rejection to initial
Repeat Problem 9–20 using constant specific heats at room temperature.
Consider a Carnot cycle executed in a closed system with 0.003 kg of air. The temperature limits of the cycle are 300 and 900 K, and the minimum and maximum pressures that occur during the cycle are 20 and 2000 kPa. Assuming constant specific heats, determine the net work output per cycle.
An air-standard Carnot cycle is executed in a closed system between the temperature limits of 350 and 1200 K. The pressures before and after the isothermal compression are 150 and 300 kPa, respectively. If the net work output per cycle is 0.5 kJ, determine (a) The maximum pressure in the cycle,
Repeat Problem 9–23 using helium as the working fluid.
Consider a Carnot cycle executed in a closed system with air as the working fluid. The maximum pressure in the cycle is 800 kPa while the maximum temperature is 750 K. If the entropy increase during the isothermal heat rejection process is 0.25 kJ/kg K and the net work output is 100 kJ/kg,
What four processes make up the ideal Otto cycle?
How do the efficiencies of the ideal Otto cycle and the Carnot cycle compare for the same temperature limits? Explain.
How is the rpm (revolutions per minute) of an actual four-stroke gasoline engine related to the number of thermodynamic cycles? What would your answer be for a two-stroke engine?
Are the processes that make up the Otto cycle analyzed as closed-system or steady-flow processes? Why?
How does the thermal efficiency of an ideal Otto cycle change with the compression ratio of the engine and the specific heat ratio of the working fluid?
Why are high compression ratios not used in spark ignition engines?
An ideal Otto cycle with a specified compression ratio is executed using (a) air, (b) argon, and (c) ethane as the working fluid. For which case will the thermal efficiency be the highest? Why?
What is the difference between fuel-injected gasoline engines and diesel engines?
An ideal Otto cycle has a compression ratio of 8. At the beginning of the compression process, air is at 95 kPa and 27°C, and 750 kJ/kg of heat is transferred to air during the constant-volume heat-addition process. Taking into account the variation of specific heats with temperature,
Reconsider Problem 9–34. Using EES (or other) software, study the effect of varying the compression ratio from 5 to 10. Plot the net work output and thermal efficiency as a function of the compression ratio. Plot the T-s and P-v diagrams for the cycle when the compression ratio is 8.
Repeat Problem 9–34 using constant specific heats at room temperature.
The compression ratio of an air-standard Otto cycle is 9.5. Prior to the isentropic compression process, the air is at 100 kPa, 35°C, and 600 cm3. The temperature at the end of the isentropic expansion process is 800 K. Using specific heat values at room temperature determine (a) The highest
Repeat Problem 9–37, but replace the isentropic expansion process by a polytropic expansion process with the polytropic exponent n = 1.35.
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
Repeat Problem 9–39E using argon as the working fluid.
A four-cylinder, four-stroke, 2.2-L gasoline engine operates on the Otto cycle with a compression ratio of 10. The air is at 100 kPa and 60°C at the beginning of the compression process, and the maximum pressure in the cycle is 8 MPa. The compression and expansion processes may be modeled as
How does a diesel engine differ from a gasoline engine?
How does the ideal Diesel cycle differ from the ideal Otto cycle?
Do diesel or gasoline engines operate at higher compression ratios? Why?
What is the cutoff ratio? How does it affect the thermal efficiency of a Diesel cycle?
An air-standard Diesel cycle has a compression ratio of 16 and a cutoff ratio of 2. At the beginning of the compression process, air is at 95 kPa and 27°C. Accounting for the variation of specific heats with temperature, determine (a) The temperature after the heat-addition process, (b) The
Repeat Problem 9–47 using constant specific heats at room temperature.
An air-standard Diesel cycle has a compression ratio of 18.2. Air is at 80°F and 14.7 psia at the beginning of the compression process and at 3000 R at the end of the heat addition process. Accounting for the variation of specific heats with temperature, determine (a) The cutoff ratio, (b) The
Repeat Problem 9–49E using constant specific heats at room temperature.
An ideal diesel engine has a compression ratio of 20 and uses air as the working fluid. The state of air at the beginning of the compression process is 95 kPa and 20°C. If the maximum temperature in the cycle is not to exceed 2200VK, determine (a) The thermal efficiency and (b) The mean
Repeat Problem 9–51, but replace the isentropic expansion process by polytropic expansion process with the polytropic exponent n = 1.35.
Reconsider Problem 9–52. Using EES (or other) software, study the effect of varying the compression ratio from 14 to 24. Plot the net work output, mean effective pressure, and thermal efficiency as a function of the compression ratio. Plot the T-s and P-v diagrams for the cycle when the
A four-cylinder two-stroke 2.4-L diesel engine that operates on an ideal Diesel cycle has a compression ratio of 17 and a cutoff ratio of 2.2. Air is at 55°C and 97 kPa at the beginning of the compression process. Using the cold-air standard assumptions, determine how much power the engine will
Repeat Problem 9–54 using nitrogen as the working fluid.
The compression ratio of an ideal dual cycle is 14. Air is at 100 kPa and 300 K at the beginning of the compression process and at 2200 K at the end of the heat-addition process. Heat transfer to air takes place partly at constant volume and partly at constant pressure, and it amounts to 1520.4
Reconsider Problem 9–56. Using EES (or other) software, study the effect of varying the compression ratio from 10 to 18. For the compression ratio equal to 14, plot the T-s and P-v diagrams for the cycle.
Repeat Problem 9–56 using constant specific heats at room temperature. Is the constant specific heat assumption reasonable in this case?
A six-cylinder, four-stroke, 4.5-L compression-ignition engine operates on the ideal diesel cycle with a compression ratio of 17. The air is at 95 kPa and 55°C at the beginning of the compression process and the engine speed is 2000 rpm. The engine uses light diesel fuel with a heating value of
Consider the ideal Otto, Sterling, and Carnot cycles operating between the same temperature limits. How would you compare the thermal efficiencies of these three cycles?
Consider the ideal Diesel, Ericsson, and Carnot cycles operating between the same temperature limits. How would you compare the thermal efficiencies of these three cycles?
How does the ideal Ericsson cycle differ from the Carnot cycle?
An ideal Ericsson engine using helium as the working fluid operates between temperature limits of 550 and 3000 R and pressure limits of 25 and 200 psia. Assuming a mass flow rate of 14 lbm/s determine (a) The thermal efficiency of the cycle, (b) The heat transfer rate in the regenerator, and
Consider an ideal Ericsson cycle with air as the working fluid executed in a steady-flow system. Air is at 27°C and 120 kPa at the beginning of the isothermal compression process, during which 150 kJ/kg of heat is rejected. Heat transfer to air occurs at 1200 K. Determine (a) The maximum
An ideal Sterling engine using helium as the working fluid operates between temperature limits of 300 and 2000 K and pressure limits of 150 kPa and 3 MPa. Assuming the mass of the helium used in the cycle is 0.12 kg, determine (a) The thermal efficiency of the cycle, (b) The amount of heat
Why are the back work ratios relatively high in gas turbine engines?
What four processes make up the simple ideal Brayton cycle?
For fixed maximum and minimum temperatures, what is the effect of the pressure ratio on (a) The thermal efficiency and (b) The net work output of a simple ideal Brayton cycle?
What is the back work ratio? What are typical back work ratio values for gas-turbine engines?
How do the inefficiencies of the turbine and the compressor affect (a) The back work ratio and (b) The thermal efficiency of a gas-turbine engine?
A simple ideal Brayton cycle with air as the working fluid has a pressure ratio of 10. The air enters the compressor at 520 R and the turbine at 2000 R. Accounting for the variation of specific heats with temperature, determine (a) The air temperature at the compressor exit, (b) The back work
A simple Brayton cycle using air as the working fluid has a pressure ratio of 8. The minimum and maximum temperatures in the cycle are 310 and 1160 K. Assuming an isentropic efficiency of 75 percent for the compressor and 82 percent for the turbine determine (a) The air temperature at the turbine
Reconsider Problem 9–73. Using EES (or other) software, allow the mass flow rate, pressure ratio, turbine inlet temperature, and the isentropic efficiencies of the turbine and compressor to vary. Assume the compressor inlet pressure is 100 kPa. Develop a general solution for the problem by taking
Repeat Problem 9–73 using constant specific heats at room temperature.
Air is used as the working fluid in a simple ideal Brayton cycle that has a pressure ratio of 12, a compressor inlet temperature of 300 K, and a turbine inlet temperature of 1000 K. Determine the required mass flow rate of air for a net power output of 70 MW, assuming both the compressor and the
A stationary gas-turbine power plant operates on a simple ideal Brayton cycle with air as the working fluid. The air enters the compressor at 95 kPa and 290 K and the turbine at 760 kPa and 1100 K. Heat is transferred to air at a rate of 35,000 kJ/s. Determine the power delivered by this plant
Air enters the compressor of a gas-turbine engine at 300 K and 100 kPa, where it is compressed to 700 kPa and 580 K. Heat is transferred to air in the amount of 950 kJ/kg before it enters the turbine. For a turbine efficiency of 86 percent, determine (a) The fraction of the turbine work output
Repeat Problem 9–78 using constant specific heats at room temperature.
A gas-turbine power plant operates on a simple Brayton cycle with air as the working fluid. The air enters the turbine at 120 psia and 2000 R and leaves at 15 psia and 1200 R. Heat is rejected to the surroundings at a rate of 6400 Btu/s, and air flows through the cycle at a rate of 40 lbm/s.
For what compressor efficiency will the gas-turbine power plant in Problem 9–80E produce zero net work?
A gas-turbine power plant operates on the simple Brayton cycle with air as the working fluid and delivers 32 MW of power. The minimum and maximum temperatures in the cycle are 310 and 900 K, and the pressure of air at the compressor exit is 8 times the value at the compressor inlet. Assuming an
Repeat Problem 9–82 using constant specific heats at room temperature.
A gas-turbine power plant operates on the simple Brayton cycle between the pressure limits of 100 and 1200 kPa. The working fluid is air, which enters the compressor at 30°C at a rate of 150 m3/min and leaves the turbine at 500°C. Using variable specific heats for air and assuming a
How does regeneration affect the efficiency of a Brayton cycle, and how does it accomplish it?
Somebody claims that at very high pressure ratios, the use of regeneration actually decreases the thermal efficiency of a gas-turbine engine. Is there any truth in this claim? Explain.
Define the effectiveness of a regenerator used in gas-turbine cycles.
In an ideal regenerator, is the air leaving the compressor heated to the temperature at (a) turbine inlet, (b) turbine exit, (c) slightly above turbine exit?
In 1903, Aegidius Elling of Norway designed and built an 11-hp gas turbine that used steam injection between the combustion chamber and the turbine to cool the combustion gases to a safe temperature for the materials available at the time. Currently there are several gas-turbine power plants that
The idea of using gas turbines to power automobiles was conceived in the 1930s, and considerable research was done in the 1940s and 1950s to develop automotive gas turbines by major automobile manufacturers such as the Chrysler and Ford corporations in the United States and Rover in the United
The 7FA gas turbine manufactured by General Electric is reported to have an efficiency of 35.9 percent in the simple-cycle mode and to produce 159 MW of net power. The pressure ratio is 14.7 and the turbine inlet temperature is 1288°C. The mass flow rate through the turbine is 1,536,000 kg/h,
Reconsider Problem 9–91. Using EES (or other) software, develop a solution that allows different isentropic efficiencies for the compressor and turbine and study the effect of the isentropic efficiencies on net work done and the heat supplied to the cycle. Plot the T-s diagram for the cycle.
An ideal Brayton cycle with regeneration has a pressure ratio of 10. Air enters the compressor at 300 K and the turbine at 1200 K. If the effectiveness of the regenerator is 100 percent, determine the net work output and the thermal efficiency of the cycle. Account for the variation of specific
Reconsider Problem 9–93. Using EES (or other) software, study the effects of varying the isentropic efficiencies for the compressor and turbine and regenerator effectiveness on net work done and the heat supplied to the cycle for the variable specific heat case. Plot the T-s diagram for the cycle.
Repeat Problem 9–93 using constant specific heats at room temperature.
A Brayton cycle with regeneration using air as the working fluid has a pressure ratio of 7. The minimum and maximum temperatures in the cycle are 310 and 1150 K. Assuming an isentropic efficiency of 75 percent for the compressor and 82 percent for the turbine and an effectiveness of 65 percent for
A stationary gas-turbine power plant operates on an ideal regenerative Brayton cycle (P = 100 percent) with air as the working fluid. Air enters the compressor at 95 kPa and 290 K and the turbine at 760 kPa and 1100 K. Heat is transferred to air from an external source at a rate of 75,000 kJ/s,
Air enters the compressor of a regenerative gas-turbine engine at 300 K and 100 kPa, where it is compressed to 800 kPa and 580 K. The regenerator has an effectiveness of 72 percent, and the air enters the turbine at 1200 K. For a turbine efficiency of 86 percent, determine (a) The amount of heat
Repeat Problem 9–98 using constant specific heats at room temperature.
Repeat Problem 9–98 for a regenerator effectiveness of 70 percent.
Under what modifications will the ideal simple gas-turbine cycle approach the Ericsson cycle?
The single-stage expansion process of an ideal Brayton cycle without regeneration is replaced by a multistage expansion process with reheating between the same pressure limits. As a result of this modification, (a) Does the turbine work increase, decrease, or remain the same? (b) Does the back
A simple ideal Brayton cycle without regeneration is modified to incorporate multistage compression with inter-cooling and multistage expansion with reheating, without changing the pressure or temperature limits of the cycle. As a result of these two modifications, (a) Does the net work output
A simple ideal Brayton cycle is modified to incorporate multistage compression with intercooling, multistage expansion with reheating, and regeneration without changing the pressure limits of the cycle. As a result of these modifications, (a) Does the net work output increase, decrease, or remain
For a specified pressure ratio, why does multistage compression with inter cooling decrease the compressor work, and multistage expansion with reheating increase the turbine work?
Consider an ideal gas-turbine cycle with two stages of compression and two stages of expansion. The pressure ratio across each stage of the compressor and turbine is 3. The air enters each stage of the compressor at 300 K and each stage of the turbine at 1200 K. Determine the back work ratio and

Showing 4300 - 4400 of 18200

First
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
Last

Step by Step Answers

Services

Sitemap
Fun
Definitions
Become Tutor
Used Textbooks
Study Help Categories
Recent Questions
Expert Questions
Campus Wear
Sell Your Books

Company Info

Security
Copyrights
Privacy Policy
Terms & Conditions
SolutionInn Fee
Scholarship
Online Quiz
Give Feedback, Get Rewards

Get In Touch

About Us
Contact Us
Career
Jobs
FAQ
Student Discount
Campus Ambassador

Secure Payment

Download Our App

© 2026 SolutionInn. All Rights Reserved