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 6.11, Problem 17P
A steam power plant receives heat from a furnace at a rate of 280 GJ/h. Heat losses to the surrounding air from the steam as it passes through the pipes and other components are estimated to be about 8 GJ/h. If the waste heat is transferred to the cooling water at a rate of 165 GJ/h, determine (a) net power output and (b) the thermal efficiency of this power plant.
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solutionStudents have asked these similar questions
A power transistor with three 0.8 mm diameter leads of a copper-silver alloy (k = 400 W/m-K) dissipates 3.5 Watts of
power. The printed circuit board (PCB) on which the transistor is mounted is maintained at 30 C. The air temperature is
20 C and the heat transfer coefficient for the leads is 60 W/m² K. The length of the leads from the transistor to printed
circuit board is 9.0 mm.
(a) Determine the maximum lead temperature neglecting all convection effects.
(b) Determine the maximum lead temperature if convection is present.
T=20C
h = 60 W/m²K
Air
Power
Transistor
Lead
k = 400 W/m K
TPCB = 30 C
9 mm
A window in a tall building experiences a horizontal wind flow parallel to the surface at a velocity of 8 m/s. The window
measures 2 m high, 1.5 m wide and 6.5 mm thick. The transition from the building wall to the window glass surface is
not smooth. The window casement that surrounds the edge of glass pane is raised 10 mm above the surface of the glass
and adjacent wall structure. Inside the building, the air temperature and heat transfer coefficient for the interior surface
are 21 °C and 9 W/m² K respectively. The window has a uniform thermal conductivity of 1.4 W/m K. If the outdoor air
temperature is 5 °C, determine the rate of convective heat loss from the window. Develop a thermal resistance network
for the window system. Please state and justify all assumptions. Neglect any conduction through the casement.
Assume the following air properties: kair =0.0248 W/m K, v= 14.20 x 106 m²/s, Pr = 0.712.
Outside Air
u=8m/s
T=5°C
casement
glass
Inside
2 m
T=21°C
h=9W/m² K
6.5 mm
1.5 m…
A thin electrical heater that dissipates 2 kW of thermal energy is position between two plane walls. The thickness of
each wall is shown in the figure below. The thermal conductivities of sections A and B are 3 W/m C and 0.8 W/m C
respectively. The electrical heater is assumed to be highly conductive (k=200 W/m C). The exterior surface of each wall
experiences convective conditions as summarized below.
(a) Construct the thermal circuit representing the steady state heat transfer for the system. Label all nodes, resistances
and relevant terms.
(b) Determine the temperate of the electrical heater.
T = 50 C
h = 200 W/m² C
A
10 cm
6 cm
B
Electrical
Heater
T_ = 20 C
h = 50 W/m² C
K₁ = 3 W/m²K
0.05 cm
k₁ = 0.08 W/m² K
Chapter 6 Solutions
Thermodynamics: An Engineering Approach
Ch. 6.11 - A mechanic claims to have developed a car engine...Ch. 6.11 - Describe an imaginary process that violates both...Ch. 6.11 - Describe an imaginary process that satisfies the...Ch. 6.11 - Describe an imaginary process that satisfies the...Ch. 6.11 - An experimentalist claims to have raised the...Ch. 6.11 - Consider the process of baking potatoes in a...Ch. 6.11 - Prob. 7PCh. 6.11 - What are the characteristics of all heat engines?Ch. 6.11 - What is the KelvinPlanck expression of the second...Ch. 6.11 - Is it possible for a heat engine to operate...
Ch. 6.11 - Does a heat engine that has a thermal efficiency...Ch. 6.11 - In the absence of any friction and other...Ch. 6.11 - Are the efficiencies of all the work-producing...Ch. 6.11 - Baseboard heaters are basically electric...Ch. 6.11 - Consider a pan of water being heated (a) by...Ch. 6.11 - A heat engine has a total heat input of 1.3 kJ and...Ch. 6.11 - A steam power plant receives heat from a furnace...Ch. 6.11 - A heat engine has a heat input of 3 104 Btu/h and...Ch. 6.11 - A 600-MW steam power plant, which is cooled by a...Ch. 6.11 - A heat engine with a thermal efficiency of 45...Ch. 6.11 - A heat engine that propels a ship produces 500...Ch. 6.11 - A steam power plant with a power output of 150 MW...Ch. 6.11 - An automobile engine consumes fuel at a rate of 22...Ch. 6.11 - Solar energy stored in large bodies of water,...Ch. 6.11 - A coal-burning steam power plant produces a net...Ch. 6.11 - An Ocean Thermal Energy Conversion (OTEC) power...Ch. 6.11 - Prob. 27PCh. 6.11 - Prob. 29PCh. 6.11 - What is the difference between a refrigerator and...Ch. 6.11 - Prob. 31PCh. 6.11 - Define the coefficient of performance of a...Ch. 6.11 - Define the coefficient of performance of a heat...Ch. 6.11 - Prob. 34PCh. 6.11 - A refrigerator has a COP of 1.5. That is, the...Ch. 6.11 - In a refrigerator, heat is transferred from a...Ch. 6.11 - A heat pump is a device that absorbs energy from...Ch. 6.11 - What is the Clausius expression of the second law...Ch. 6.11 - Show that the KelvinPlanck and the Clausius...Ch. 6.11 - The coefficient of performance of a residential...Ch. 6.11 - A food freezer is to produce a 5-kW cooling...Ch. 6.11 - An automotive air conditioner produces a 1-kW...Ch. 6.11 - A food refrigerator is to provide a 15,000-kJ/h...Ch. 6.11 - Prob. 44PCh. 6.11 - Determine the COP of a heat pump that supplies...Ch. 6.11 - Prob. 46PCh. 6.11 - A heat pump with a COP of 1.4 is to produce a...Ch. 6.11 - An air conditioner removes heat steadily from a...Ch. 6.11 - A household refrigerator that has a power input of...Ch. 6.11 - When a man returns to his well-sealed house on a...Ch. 6.11 - Water enters an ice machine at 55F and leaves as...Ch. 6.11 - A refrigerator is used to cool water from 23 to 5C...Ch. 6.11 - A household refrigerator runs one-fourth of the...Ch. 6.11 - Consider an office room that is being cooled...Ch. 6.11 - A house that was heated by electric resistance...Ch. 6.11 - Refrigerant-134a enters the condenser of a...Ch. 6.11 - Refrigerant-134a enters the evaporator coils...Ch. 6.11 - An inventor claims to have developed a resistance...Ch. 6.11 - Prob. 60PCh. 6.11 - Why are engineers interested in reversible...Ch. 6.11 - A cold canned drink is left in a warmer room where...Ch. 6.11 - A block slides down an inclined plane with...Ch. 6.11 - Prob. 64PCh. 6.11 - Prob. 65PCh. 6.11 - Show that processes that use work for mixing are...Ch. 6.11 - Why does a nonquasi-equilibrium compression...Ch. 6.11 - Prob. 68PCh. 6.11 - Prob. 69PCh. 6.11 - What are the four processes that make up the...Ch. 6.11 - Prob. 71PCh. 6.11 - Prob. 72PCh. 6.11 - Prob. 73PCh. 6.11 - Somebody claims to have developed a new reversible...Ch. 6.11 - Is there any way to increase the efficiency of a...Ch. 6.11 - Consider two actual power plants operating with...Ch. 6.11 - You are an engineer in an electric-generation...Ch. 6.11 - Prob. 78PCh. 6.11 - A thermodynamicist claims to have developed a heat...Ch. 6.11 - A heat engine is operating on a Carnot cycle and...Ch. 6.11 - A completely reversible heat engine operates with...Ch. 6.11 - An inventor claims to have developed a heat engine...Ch. 6.11 - A Carnot heat engine operates between a source at...Ch. 6.11 - A heat engine is operating on a Carnot cycle and...Ch. 6.11 - A heat engine operates between a source at 477C...Ch. 6.11 - An experimentalist claims that, based on his...Ch. 6.11 - In tropical climates, the water near the surface...Ch. 6.11 - Prob. 89PCh. 6.11 - Prob. 90PCh. 6.11 - Prob. 91PCh. 6.11 - Prob. 92PCh. 6.11 - How can we increase the COP of a Carnot...Ch. 6.11 - In an effort to conserve energy in a heat-engine...Ch. 6.11 - Prob. 95PCh. 6.11 - Prob. 96PCh. 6.11 - A thermodynamicist claims to have developed a heat...Ch. 6.11 - Determine the minimum work per unit of heat...Ch. 6.11 - Prob. 99PCh. 6.11 - An air-conditioning system operating on the...Ch. 6.11 - A heat pump operates on a Carnot heat pump cycle...Ch. 6.11 - An air-conditioning system is used to maintain a...Ch. 6.11 - A Carnot refrigerator absorbs heat from a space at...Ch. 6.11 - Prob. 104PCh. 6.11 - A Carnot refrigerator operates in a room in which...Ch. 6.11 - Prob. 106PCh. 6.11 - A commercial refrigerator with refrigerant-134a as...Ch. 6.11 - Prob. 108PCh. 6.11 - A heat pump is to be used for heating a house in...Ch. 6.11 - A completely reversible heat pump has a COP of 1.6...Ch. 6.11 - A Carnot heat pump is to be used to heat a house...Ch. 6.11 - A Carnot heat engine receives heat from a...Ch. 6.11 - Prob. 113PCh. 6.11 - Derive an expression for the COP of a completely...Ch. 6.11 - Calculate and plot the COP of a completely...Ch. 6.11 - Prob. 116PCh. 6.11 - Prob. 117PCh. 6.11 - Prob. 118PCh. 6.11 - Someone proposes that the entire...Ch. 6.11 - Prob. 120PCh. 6.11 - Prob. 121PCh. 6.11 - Prob. 122PCh. 6.11 - It is commonly recommended that hot foods be...Ch. 6.11 - It is often stated that the refrigerator door...Ch. 6.11 - Prob. 125RPCh. 6.11 - Prob. 126RPCh. 6.11 - Prob. 127RPCh. 6.11 - A Carnot heat pump is used to heat and maintain a...Ch. 6.11 - A refrigeration system uses a water-cooled...Ch. 6.11 - A refrigeration system is to cool bread loaves...Ch. 6.11 - A heat pump with a COP of 2.8 is used to heat an...Ch. 6.11 - Prob. 132RPCh. 6.11 - Consider a Carnot heat-engine cycle executed in a...Ch. 6.11 - Prob. 134RPCh. 6.11 - Consider a Carnot refrigeration cycle executed in...Ch. 6.11 - Prob. 137RPCh. 6.11 - Consider two Carnot heat engines operating in...Ch. 6.11 - A heat engine operates between two reservoirs at...Ch. 6.11 - An old gas turbine has an efficiency of 21 percent...Ch. 6.11 - Prob. 141RPCh. 6.11 - Prob. 142RPCh. 6.11 - Prob. 143RPCh. 6.11 - The drinking water needs of a production facility...Ch. 6.11 - Prob. 145RPCh. 6.11 - Prob. 147RPCh. 6.11 - Prob. 148RPCh. 6.11 - Prob. 149RPCh. 6.11 - Prob. 150RPCh. 6.11 - Prob. 151RPCh. 6.11 - A heat pump with refrigerant-134a as the working...Ch. 6.11 - Prob. 153RPCh. 6.11 - Prob. 155RPCh. 6.11 - Prob. 156RPCh. 6.11 - Prob. 157RPCh. 6.11 - Prove that a refrigerators COP cannot exceed that...Ch. 6.11 - Consider a Carnot refrigerator and a Carnot heat...Ch. 6.11 - A 2.4-m-high 200-m2 house is maintained at 22C by...Ch. 6.11 - A window air conditioner that consumes 1 kW of...Ch. 6.11 - The drinking water needs of an office are met by...Ch. 6.11 - The label on a washing machine indicates that the...Ch. 6.11 - A heat pump is absorbing heat from the cold...Ch. 6.11 - A heat engine cycle is executed with steam in the...Ch. 6.11 - A heat pump cycle is executed with R134a under the...Ch. 6.11 - A refrigeration cycle is executed with R-134a...Ch. 6.11 - A heat pump with a COP of 3.2 is used to heat a...Ch. 6.11 - A heat engine cycle is executed with steam in the...Ch. 6.11 - A heat engine receives heat from a source at 1000C...Ch. 6.11 - An air-conditioning system operating on the...Ch. 6.11 - A refrigerator is removing heat from a cold medium...Ch. 6.11 - Two Carnot heat engines are operating in series...Ch. 6.11 - A typical new household refrigerator consumes...
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
- I need answer with diagram and not from AIarrow_forwardOne -1/x²-10.5x+1Z 84.5 11 2x2 +212 +382 2 2 -23.500 81 4th Year 24. (i) Derive a mathematical model for the mechanical system represented below, where the input Automation and Control is the Force F, and the output is the displacement x. (ii)Determine the general transfer function of the system given that the input is an impulsive force of 10N and the following constants (iii\Determine the output as a F(s) (iii) What is the output x as a function of time? EX Rnd 0 COM 7 4 Ran# Ra 25 (N/m) 5 kg 30 (N.s/m) Ans(i) ref notes 2 2 s² + 6s+5 25. A control system has a forward path transfer function of (111) (iii) x(t) = 0.5(e-t-e-5t) 2 and a negative feedback loop four S+2 with a transfer function 4. What will be the (time) response of the system to a unit step input? Ans: 0.2(1-e-10) 10 26. A control system has a forward path transfer function of and a negative feedback loop S+3 with a transfer function 5. What will be the (time) response of the system to a (a) unit impulsive input? (b) a…arrow_forwardfour One -H = 2x2 +212 +382 2 x² -23.5x + x37 84 x -10.5x+h 84.5 Automation and Control 4th Year 24. (i) Derive a mathematical model for the mechanical system represented below, where the input is the Force F, and the output is the displacement x. (ii)Determine the general transfer function of the system given that the input is an impulsive force of 10N and the following constants (iii\Determine the output as a F(s) (iii) What is the output x as a function of time? 25 (N/m) F 5 kg 30 (N.s/m) 2 Ans(i) ref notes (iii) (iii) x(t) = 0.5(e-t-e-st) 2 and a negative feedback loop S+2 s² + 6s+5 25. A control system has a forward path transfer function of with a transfer function 4. What will be the (time) response of the system to a unit step input? CON 4 1 Rnd Rane R 0 EL SALVADOR Ans: 0.2(1-e-10) 10 s+3 and a negative feedback loop 26. A control system has a forward path transfer function of with a transfer function 5. What will be the (time) response of the system to a (a) unit impulsive…arrow_forward
- find the temperature distribution of the beam shown below, take &=o.!! and L-1m- of C" loko -10C" 30 со h2 5 Kwlm²-ko T = 250° q=30twarrow_forwardQ1/Create an estimated (S-N) diagram and define its equation for an axial fully reversed loaded steel bar. Its cross section shown in figure (1). Determine the life in cycle that can be expected if the alternating stress is (127Mpa). The bar surface finch is hot rolled. The operating temperature is (506 Co) and (du-577 Mpa). 120 mm. 4arrow_forwardQ4/ Find using a proper design theory the safety factor (N) based on point A for the circular cantilever rod of a diameter (94 mm) shown in figure 3. Knowing that the rod is made of Stainless Steel Type 304-cold rolled, Which is subjected to a force (F= 6.4 kN) inclined with y-axis by 0-72° and to a torque (T= 265π N. m). Fig.3 L1=3.2 cm L2= 3.6 cm F Z Y X (15 Marks) Q5/ Create an estimated S-N diagram and define its equation for an aluminum rectangular bar, shown in figure 4 below, with a (out=342Mpa). The bar is loaded in a fully reversed bending and the bar radius is 12 mm. Determine also the corrected fatigue strength at (N=2.3* 107 cycles). Knowing that the bar surface finch is ground, the operating temperature is 155 C°, and Take a 99.99% reliability factor. Fig. 4 h=5.6 cm Head of the Department: Dr. Deyaa Hassan Jawad Al-Jashami b=4 cm *** Best of Luck *** (15 Marks) Examiner: Ass. Lect. Ahmed A. Tomanarrow_forward
- University of Babylon Collage of Engineering\Al-Musayab Department of Automobile Engineering Under Grad/Third stage Notes: 1-Attempt Four Questions. 2- Q4 Must be Answered 3-Assume any missing data. 4 تسلم الأسئلة بعد الامتحان مع الدفتر Subject: Mechanical Element Design I Date: 2022\01\25 2022-2023 Time: Three Hours Course 1 Attempt 1 Q1/ Design a thin cylindrical pressure tank (pressure vessel) with hemispherical ends to the automotive industry, shown in figure I below. Design for an infinite life by finding the appropriate thickness of the vessel to carry a sinusoidal pressure varied from {(-0.1) to (6) Mpa}. The vessel is made from Stainless Steel Alloy-Type 316 sheet annealed. The operating temperature is 80 C° and the dimeter of the cylinder is 36 cm. use a safety factor of 1.8. Fig. 1 (15 Marks) Q2/ Answer the following: 1- Derive the design equation for the direct evaluation of the diameter of a shaft to a desired fatigue safety factor, if the shaft subjected to both fluctuated…arrow_forwardwhat is the scientific interpetation of all of what comes: 1- axial loading 2- Direct shear loading 3- Torsional loading 4. Bending load 4- Explain it in detail and how to use it to solve mechanical design Problemsarrow_forwardConsider the magnetic levitation system shown in Figure 1. An electromagnet is located at the upper part of the experimental system. Using the electromagnetic force f, you want to suspend the iron ball. Assume that the state variables are x₁ = x, x2 = x, and x3 =i. The electromagnet has an inductance L = 0.508H and a resistance R = 23.2. Use a Taylor series approximation for the electromagnetic force. The current is i₁ = 10 + i, where I = 1.06A is the operating point and i is the variable. The mass m is equal to 1.75kg. The gap is x = x + x, where x = 4.36mm is the operating point and x is the variable. The electromagnetic force is f = k(₁₁/xg)², where k = 2.9 × 10-4 Nm²/A². a) Determine the state matrix differential equation. b) Find the equivalent transfer function X(s)/V(s). Note: v(t) (+ Electromagnet i₁(t) Iron ball Force f(t) x(t) mg Gap sensor Figure 1 The magnetic levitation system is essentially unworkable. Hence, feedback control is crucial. A standard induction probe of the…arrow_forward
- Q3/ a steel plate shown in figure (3): Su689 Mpa, reliability is 90%, factor of safety is 2, the size factor is 0.87. machined surface. Determine the plate thickness (t) for infinite life. Note: All dimensions are in mm. P= ± 50 kN 100 Fig. 3 177 5r P = ± 50 kN 540 50arrow_forwardQ2/A cantilever beam, shown in figure (2), is to be made from [Wrought-Aluminum Alloys- 3003- cold rolled]. If the desired design factor is (N-2.5), (P-4kN), and (F-6kN). Using a suitable failure theory, find the appropriate beam thickness h. T D=15cm d=100mm r=20mm L= 25 cm Karrow_forwardSolve full assignment with steps pleasearrow_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
Thermodynamic Availability, What is?; Author: MechanicaLEi;https://www.youtube.com/watch?v=-04oxjgS99w;License: Standard Youtube License