Thermodynamics: An Engineering Approach
9th Edition
ISBN: 9781259822674
Author: Yunus A. Cengel Dr., Michael A. Boles
Publisher: McGraw-Hill Education
expand_more
expand_more
format_list_bulleted
Textbook Question
Chapter 10.9, Problem 119RP
A solar collector system delivers heat to a power plant. It is well known that the thermal collection efficiency ηsc of a solar collector diminishes with increasing solar collection output temperature TH, or ηsc = A – BTH where A and B are known constants. The thermal efficiency of the power plant ηth is a fixed fraction of the Carnot thermal efficiency, such that ηth = F(1 – TL/TH) where F is a known constant assumed here independent of temperatures and TL is the condenser temperature, also constant for this problem. Here, the solar collection temperature TH is also taken to be the source temperature for the power plant.
- (a) At what temperature TH should the solar collector be operated to obtain the maximum overall system efficiency?
- (b) Develop an expression for the maximum overall system efficiency.
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solutionStudents have asked these similar questions
A cycle has a qin=350Btu/lbm, and a thermal efficiency of 74%. In this case, the network produced by the cycle is most likely:
320 Btu/lbm
90 Btu/lbm
260 Btu/lbm
350 Btu/lbm
5. A 2000-KW diesel engine unit uses 1 US barrel (bbl) of oil per 525 kW-h produced. Oil is 25°API. Efficiency of generator is 93%
and mechanical efficiency is 80%. The thermal efficiency based on indicated power is %.
1. In an analysis, a heat engine based on the Carnot cycle operating between 1000 0C and 300 0C. The heat rejected from this engine to the sink was at a rate of 800 kJ/min. Determine the thermal efficiency (in %) and power output (in kW) of the engin
2.You found out that the power output of your dream car is the same as the sum of each digits of your student number (in kW) with a percentage thermal efficiency the same as the first four digit of your student number divided by 100. The calorific value of the fuel available has a calorific value of 40 000 kJ/kg. Assuming a constant power output from the car, calculate the heat transfer rate (in kW) and the fuel consumption rate (in kg/h)
Chapter 10 Solutions
Thermodynamics: An Engineering Approach
Ch. 10.9 - Why is the Carnot cycle not a realistic model for...Ch. 10.9 - Why is excessive moisture in steam undesirable in...Ch. 10.9 - A steady-flow Carnot cycle uses water as the...Ch. 10.9 - A steady-flow Carnot cycle uses water as the...Ch. 10.9 - Consider a steady-flow Carnot cycle with water as...Ch. 10.9 - Water enters the boiler of a steady-flow Carnot...Ch. 10.9 - What four processes make up the simple ideal...Ch. 10.9 - Consider a simple ideal Rankine cycle with fixed...Ch. 10.9 - Consider a simple ideal Rankine cycle with fixed...Ch. 10.9 - Consider a simple ideal Rankine cycle with fixed...
Ch. 10.9 - How do actual vapor power cycles differ from...Ch. 10.9 - Compare the pressures at the inlet and the exit of...Ch. 10.9 - The entropy of steam increases in actual steam...Ch. 10.9 - Is it possible to maintain a pressure of 10 kPa in...Ch. 10.9 - A simple ideal Rankine cycle with water as the...Ch. 10.9 - A simple ideal Rankine cycle with water as the...Ch. 10.9 - A simple ideal Rankine cycle which uses water as...Ch. 10.9 - Consider a solar-pond power plant that operates on...Ch. 10.9 - Consider a 210-MW steam power plant that operates...Ch. 10.9 - Consider a 210-MW steam power plant that operates...Ch. 10.9 - A simple ideal Rankine cycle with water as the...Ch. 10.9 - A simple ideal Rankine cycle with water as the...Ch. 10.9 - A steam Rankine cycle operates between the...Ch. 10.9 - A steam Rankine cycle operates between the...Ch. 10.9 - A simple Rankine cycle uses water as the working...Ch. 10.9 - The net work output and the thermal efficiency for...Ch. 10.9 - A binary geothermal power plant uses geothermal...Ch. 10.9 - Consider a coal-fired steam power plant that...Ch. 10.9 - Show the ideal Rankine cycle with three stages of...Ch. 10.9 - Is there an optimal pressure for reheating the...Ch. 10.9 - How do the following quantities change when a...Ch. 10.9 - Consider a simple ideal Rankine cycle and an ideal...Ch. 10.9 - Consider a steam power plant that operates on the...Ch. 10.9 - Consider a steam power plant that operates on the...Ch. 10.9 - An ideal reheat Rankine cycle with water as the...Ch. 10.9 - Steam enters the high-pressure turbine of a steam...Ch. 10.9 - An ideal reheat Rankine cycle with water as the...Ch. 10.9 - A steam power plant operates on an ideal reheat...Ch. 10.9 - Consider a steam power plant that operates on a...Ch. 10.9 - Repeat Prob. 1041 assuming both the pump and the...Ch. 10.9 - Prob. 43PCh. 10.9 - Prob. 44PCh. 10.9 - How do open feedwater heaters differ from closed...Ch. 10.9 - How do the following quantities change when the...Ch. 10.9 - Cold feedwater enters a 200-kPa open feedwater...Ch. 10.9 - In a regenerative Rankine cycle. the closed...Ch. 10.9 - A steam power plant operates on an ideal...Ch. 10.9 - A steam power plant operates on an ideal...Ch. 10.9 - A steam power plant operates on an ideal...Ch. 10.9 - Consider an ideal steam regenerative Rankine cycle...Ch. 10.9 - Consider a steam power plant that operates on the...Ch. 10.9 - Consider a steam power plant that operates on the...Ch. 10.9 - Consider a steam power plant that operates on the...Ch. 10.9 - A steam power plant operates on an ideal...Ch. 10.9 - Repeat Prob. 1060, but replace the open feedwater...Ch. 10.9 - A steam power plant operates on an ideal...Ch. 10.9 - A simple ideal Rankine cycle with water as the...Ch. 10.9 - Prob. 64PCh. 10.9 - An ideal reheat Rankine cycle with water as the...Ch. 10.9 - Consider a steam power plant that operates on a...Ch. 10.9 - Prob. 67PCh. 10.9 - A steam power plant operates on an ideal...Ch. 10.9 - The schematic of a single-flash geothermal power...Ch. 10.9 - What is the difference between cogeneration and...Ch. 10.9 - Prob. 71PCh. 10.9 - Prob. 72PCh. 10.9 - Consider a cogeneration plant for which the...Ch. 10.9 - Steam is generated in the boiler of a cogeneration...Ch. 10.9 - A large food-processing plant requires 1.5 lbm/s...Ch. 10.9 - An ideal cogeneration steam plant is to generate...Ch. 10.9 - Steam is generated in the boiler of a cogeneration...Ch. 10.9 - Consider a cogeneration power plant modified with...Ch. 10.9 - Prob. 80PCh. 10.9 - Why is the combined gassteam cycle more efficient...Ch. 10.9 - The gas-turbine portion of a combined gassteam...Ch. 10.9 - A combined gassteam power cycle uses a simple gas...Ch. 10.9 - Reconsider Prob. 1083. An ideal regenerator is...Ch. 10.9 - Reconsider Prob. 1083. Determine which components...Ch. 10.9 - Consider a combined gassteam power plant that has...Ch. 10.9 - Prob. 89PCh. 10.9 - What is the difference between the binary vapor...Ch. 10.9 - Why is mercury a suitable working fluid for the...Ch. 10.9 - Why is steam not an ideal working fluid for vapor...Ch. 10.9 - By writing an energy balance on the heat exchanger...Ch. 10.9 - Prob. 94RPCh. 10.9 - Steam enters the turbine of a steam power plant...Ch. 10.9 - Consider a steam power plant operating on the...Ch. 10.9 - A steam power plant operates on an ideal Rankine...Ch. 10.9 - Consider a steam power plant that operates on a...Ch. 10.9 - Repeat Prob. 1098 assuming both the pump and the...Ch. 10.9 - Consider an ideal reheatregenerative Rankine cycle...Ch. 10.9 - Prob. 101RPCh. 10.9 - A textile plant requires 4 kg/s of saturated steam...Ch. 10.9 - Consider a cogeneration power plant that is...Ch. 10.9 - Prob. 104RPCh. 10.9 - Prob. 105RPCh. 10.9 - Reconsider Prob. 10105E. It has been suggested...Ch. 10.9 - Reconsider Prob. 10106E. During winter, the system...Ch. 10.9 - Prob. 108RPCh. 10.9 - Prob. 109RPCh. 10.9 - A steam power plant operates on an ideal...Ch. 10.9 - A Rankine steam cycle modified for reheat, a...Ch. 10.9 - Show that the thermal efficiency of a combined...Ch. 10.9 - Prob. 118RPCh. 10.9 - A solar collector system delivers heat to a power...Ch. 10.9 - Starting with Eq. 1020, show that the exergy...Ch. 10.9 - Consider a simple ideal Rankine cycle with fixed...Ch. 10.9 - Consider a simple ideal Rankine cycle. If the...Ch. 10.9 - Consider a simple ideal Rankine cycle with fixed...Ch. 10.9 - Consider a simple ideal Rankine cycle with fixed...Ch. 10.9 - Consider a steady-flow Carnot cycle with water as...Ch. 10.9 - Prob. 126FEPCh. 10.9 - Prob. 127FEPCh. 10.9 - A simple ideal Rankine cycle operates between the...Ch. 10.9 - Pressurized feedwater in a steam power plant is to...Ch. 10.9 - Consider a steam power plant that operates on the...Ch. 10.9 - Consider a combined gas-steam power plant. Water...
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
- thermodynamicsarrow_forwardQuestion 5 A cyclic system exchanges heat with 3 reservoirs. The system receives 990 J from a reservoir at 1,236 Kand 542 J from a reservoir at 766 K. It rejects an unknown quantity of heat to a reservoir at 256 K. What is the maximum possible efficiency of the system? Give your answer as a percentage to 1 decimal place (e.g. 12.3% would be input as 12.3).arrow_forwardA group is considering installing a solar power station and has asked you for your recommendation if it should be a photovoltaic system or a solar thermal system. At this stage you are asked not to include cost factors. The single point design condition they have given you is for an incident solar radiation on the collector of 550 W/m2, a surrounding temperature of 18 C. The dead state for this problem should be taken as To = 291 K, Po = 1 bar. You can perform your analysis at steady state conditions. In addition to determining the power output and first law efficiency of the options, you have been requested to determine the exergy destroyed for each of them. The photovoltaic system has an efficiency of 0.15 defined as the power output/incident solar radiation. The basic photovoltaic collector is 1.1 m2 and losses heat from both the front and back surface. The edge area can be neglected. The convective heat transfer coefficient is 10 W/m2 K. The inverter and signal…arrow_forward
- A group is considering installing a solar power station and has asked you for your recommendation if it should be a photovoltaic system or a solar thermal system. At this stage you are asked not to include cost factors. The single point design condition they have given you is for an incident solar radiation on the collector of 550 W/m2, a surrounding temperature of 18 C. The dead state for this problem should be taken as To = 291 K, Po = 1 bar. You can perform your analysis at steady state conditions. In addition to determining the power output and first law efficiency of the options, you have been requested to determine the exergy destroyed for each of them. The photovoltaic system has an efficiency of 0.15 defined as the power output/incident solar radiation. The basic photovoltaic collector is 1.1 m2 and losses heat from both the front and back surface. The edge area can be neglected. The convective heat transfer coefficient is 10 W/m2 K. The inverter and signal conditioning…arrow_forwardAn electric home stove with 3 burners and microwave is used in preparing a meal as follows. Burner 1: 20 minutes Burner 2: 40 minutes Burner 3: 15 minutes . Microwave: 30 minutes. If each burner is rated at 1.2 kW and the oven at 1.8 kW, and electricity costs 1000 (IQ =Iraqi Dinar) per k Wh, calculate the cost of electricity used in preparing the meal?arrow_forwardThermodynamics 1arrow_forward
- Electrical Engineering Define the thermal efficiency of the reheat cycle shown in the T-S diagram below using the enthalpy at each point. 3 2 7. 5arrow_forwardThe number is 9 thermodynamicsarrow_forwardA cycle has a qin=350Btu/lbm, and a thermal efficiency of 74%. In this case, the expected heat rejected qout is most likely: 320 Btu/lbm 90 Btu/lbm 350 Btu/lbm 260 Btu/lbmarrow_forward
- I have been working on this problem for a while and keep getting wrong answers with many different meathods how do I solve for Q0 here?arrow_forwardA student buys a 5000 Btu window air conditioner for his apartment bedroom. He monitors it for one hour on a hot day and determines that it operates approximately 60 percent of the time (duty cycle = 60 percent) to keep the room at nearly constant temperature. (a) Showing all your work and using unity conversion ratios, calculate the rate of heat transfer into the bedroom through the walls, windows, etc. in units of Btu/h and in units of kW. (b) If the energy efficiency ratio (EER) of the air conditioner is 9.0 and electricity costs 7.5 cents per kilowatt-hr, calculate how much it costs (in cents) for him to run the air conditioner for one hour.arrow_forwardb) Refrigerators are systems that are used to remove heat from a cooled space then reject heat to a space of higher temperature. Consider a refrigerator operating at normal conditions, removing heat from a cool space at a rate of 150 kJ/min to ensure the refrigerated space is kept at -5 °C. If the surrounding air is at 27 °C and assuming that the refrigerator is operating as a Carnot cycle, determine: 1) The rate of heat being rejected to the surrounding in kJ/min The coefficient of performance of this refrigeration process 11) 111) The minimum required power on this process (give your answer in kW)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
The Refrigeration Cycle Explained - The Four Major Components; Author: HVAC Know It All;https://www.youtube.com/watch?v=zfciSvOZDUY;License: Standard YouTube License, CC-BY