Heat and Mass Transfer: Fundamentals and Applications
5th Edition
ISBN: 9780073398181
Author: Yunus A. Cengel Dr., Afshin J. Ghajar
Publisher: McGraw-Hill Education
expand_more
expand_more
format_list_bulleted
Videos
Textbook Question
Chapter 4, Problem 139P
A long roll of 2-m-wide and 0.5-cm-thick 1-Mn manganese steel plate coming off a furnace at 820°C is to be quenched in an oil bath
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solution
Students have asked these similar questions
4- Carbon steel balls 8 mm in diameter are annealed by heating them first to 900°C in a
furnace and then allowing them to cool slowly to 100°C in ambient air at 35°C. If the
average heat transfer coefficient is 75 W/m -°C, determine how long the annealing process
will take. If 2500 balls are to be annealed per hour
Given:
Carbon steel [k = 54 W/m.°C, p = 7833 kg/m, and C,= 0.465 kJ/kg. °C. and a= 1.474x 10* m²/s]
Air, 35°C
Fumace
Steel ball 100°C
900°C
Awatermelon initially at 35°C s to be cooled by dropping it into a lake at 15 °C. After 4 h and 40 min of cooling, the center temperature of watermelon is measured to be 20°C. Treating the watermelon as a 20-cm-diameter sphere and using the properties k= 0.618 W/m-K, a = 0.15 x 10-6 m2/s, p = 995 ka/m3, and cp= 4.18 kJ/kg'K, determine the average heat transfer coefficient and the surface temperature of watermelon at the end of the cooling period.
A fabricated food, in the form of small spherical pellets, is to be frozen in an air-blast freezer. The air-blast freezer isoperating with air at -40°C. The initial product temperatureis 25°C. The pellets have a diameter of 0.5 cm, and the density of the product is 980 kg/m3. The initial freezing temperature is -2.5°C. The latent heat of fusion for this product is 280 kJ/kg. The thermal conductivity of the frozen productis 1.9 W/(m°C). The convective heat transfer coefficient is 50 W/(m2 °C). Calculate the freezing time.
Chapter 4 Solutions
Heat and Mass Transfer: Fundamentals and Applications
Ch. 4 - What is the physical significance of the Biot...Ch. 4 - What is lumped system analysis? When is it...Ch. 4 - In what medium is the lumped system analysis more...Ch. 4 - For which solid is the lumped system analysis more...Ch. 4 - For which kinds of bodies made of the same...Ch. 4 - Consider heat transfer between two identical hot...Ch. 4 - Consider heat transfer between two identical hot...Ch. 4 - Consider a hot baked potato on a plate. The...Ch. 4 - Consider a potato being baked in an oven that is...Ch. 4 - Consider two identical 4-kg pieces of roast beef....
Ch. 4 - Consider a sphere and a cylinder of equal volume...Ch. 4 - Obtain relations for the characteristic lengths of...Ch. 4 - Obtain a relation for the time required for a...Ch. 4 - A brick of 20310257mm in dimension is being burned...Ch. 4 - Prob. 15PCh. 4 - Prob. 16PCh. 4 - Metal plates...Ch. 4 - Prob. 18PCh. 4 - Prob. 19PCh. 4 - A 6-mm-thick stainless steel strip...Ch. 4 - After heat treatment, the 2-cm-thick metal plates...Ch. 4 - A long copper rod of diameter 2.0 cm is initially...Ch. 4 - Prob. 23PCh. 4 - Steel rods...Ch. 4 - To warm up some milk for a baby, a mother pours...Ch. 4 - A person is found dead at 5 p.m. in a room whose...Ch. 4 - Prob. 27PCh. 4 - In an experiment, the temperature of a hot gas...Ch. 4 - Prob. 29PCh. 4 - Pulverized coal particles are used in oxy-fuel...Ch. 4 - Oxy-fuel combustion power plants use pulverized...Ch. 4 - Plasma spraying is a process used for coating a...Ch. 4 - Consider a spherical shell satellite with outer...Ch. 4 - Prob. 34PCh. 4 - Prob. 35PCh. 4 - Prob. 36EPCh. 4 - Consider a sphere of diameter 5 cm, a cube of side...Ch. 4 - Prob. 38PCh. 4 - An egg is to be cooked to a certain level of...Ch. 4 - What is an infinitely long cylinder? When is it...Ch. 4 - What is the physical significance of the Fourier...Ch. 4 - Prob. 42CPCh. 4 - Prob. 43CPCh. 4 - Prob. 44CPCh. 4 - The Biot number during a heat transfer process...Ch. 4 - A body at an initial temperature of Ti, is brought...Ch. 4 - Prob. 47PCh. 4 - In a meat processing plant, 2-cm-thick steaks...Ch. 4 - Prob. 49PCh. 4 - Prob. 50PCh. 4 - Prob. 51PCh. 4 - Layers of 23-cm-thick meat slabs...Ch. 4 - Prob. 53PCh. 4 - Prob. 54PCh. 4 - Prob. 55EPCh. 4 - Prob. 56PCh. 4 - Prob. 57EPCh. 4 - Prob. 58PCh. 4 - A 30-cm-diameter, 4-m-high cylindrical column of a...Ch. 4 - Prob. 60PCh. 4 - Prob. 61PCh. 4 - Prob. 62PCh. 4 - Prob. 63PCh. 4 - Prob. 64PCh. 4 - Prob. 65PCh. 4 - Prob. 66PCh. 4 - Prob. 67PCh. 4 - Prob. 68PCh. 4 - Prob. 69PCh. 4 - For heat transfer purposes, an egg can be...Ch. 4 - Citrus fruits are very susceptible to cold...Ch. 4 - Prob. 72PCh. 4 - Prob. 73PCh. 4 - A 9-cm-diameter potato...Ch. 4 - Chickens with an average mass of 1.7 kg...Ch. 4 - Prob. 76PCh. 4 - In Betty Crocker s Cookbook, it is stated that it...Ch. 4 - Prob. 78PCh. 4 - Prob. 79PCh. 4 - Oranges of 2.5-in-diameter...Ch. 4 - Prob. 81EPCh. 4 - Under what conditions can a plane wall be treated...Ch. 4 - What is a semi-infinite medium? Give examples of...Ch. 4 - Consider a hot semi-infinite solid at an initial...Ch. 4 - Prob. 85EPCh. 4 - Prob. 86PCh. 4 - In areas where the air temperature remains below...Ch. 4 - Prob. 88PCh. 4 - A highway made of asphalt is initially at a...Ch. 4 - A thick aluminum block initially at 20C is...Ch. 4 - Prob. 91PCh. 4 - A thick wall made of refractory bricks...Ch. 4 - Prob. 93PCh. 4 - Prob. 94PCh. 4 - A thick wood slab (k=0.17W/m.K,=1.2810-7m2/s) and...Ch. 4 - Prob. 96PCh. 4 - Prob. 97PCh. 4 - Prob. 98PCh. 4 - Prob. 99PCh. 4 - Prob. 100PCh. 4 - Prob. 101PCh. 4 - A barefooted person whose feet are at 32C steps on...Ch. 4 - What is the product solution method? How is it...Ch. 4 - How is the product solution used to determine the...Ch. 4 - Prob. 105CPCh. 4 - Consider a short cylinder whose top and bottom...Ch. 4 - Prob. 107PCh. 4 - Prob. 108PCh. 4 - A hot dog can be considered to be a cylinder 5 in...Ch. 4 - Prob. 110PCh. 4 - Prob. 111PCh. 4 - A 2-cm-high cylindrical ice block...Ch. 4 - Prob. 113PCh. 4 - Prob. 114PCh. 4 - Prob. 115PCh. 4 - Prob. 116PCh. 4 - Prob. 117PCh. 4 - Prob. 118PCh. 4 - Prob. 119CPCh. 4 - How does refrigeration prevent or delay the...Ch. 4 - What are the environmental factors that affect the...Ch. 4 - What is the effect of cooking on the...Ch. 4 - Prob. 123CPCh. 4 - Prob. 124CPCh. 4 - Prob. 125CPCh. 4 - Prob. 126CPCh. 4 - How does the rate of freezing affect the...Ch. 4 - Prob. 128CPCh. 4 - Prob. 129CPCh. 4 - Prob. 130CPCh. 4 - Prob. 131CPCh. 4 - Prob. 132CPCh. 4 - Prob. 133PCh. 4 - Prob. 134PCh. 4 - Chickens with an average mass of 2.2 kg and...Ch. 4 - Prob. 136EPCh. 4 - Prob. 137PCh. 4 - Prob. 138PCh. 4 - A long roll of 2-m-wide and 0.5-cm-thick 1-Mn...Ch. 4 - Prob. 140PCh. 4 - Prob. 141PCh. 4 - Prob. 142PCh. 4 - During a picnic on a hot summer day, the only...Ch. 4 - Two metal rods are being heated in an oven with...Ch. 4 - Stainless steel ball bearings...Ch. 4 - Prob. 146PCh. 4 - Prob. 147PCh. 4 - In Betty crockers Cookbook, it is stated that it...Ch. 4 - A watermelon initially at 35C is to be cooled by...Ch. 4 - Prob. 150PCh. 4 - Prob. 151PCh. 4 - Prob. 152PCh. 4 - Prob. 153PCh. 4 - Prob. 154PCh. 4 - Prob. 155PCh. 4 - Prob. 156PCh. 4 - Prob. 157PCh. 4 - Prob. 158PCh. 4 - Prob. 159PCh. 4 - Lumped system analysis of transient heat...Ch. 4 - Prob. 161PCh. 4 - Prob. 162PCh. 4 - An 18-cm-long, 16-cm-wide, and 12-cm-high hot iron...Ch. 4 - Prob. 164PCh. 4 - Prob. 165PCh. 4 - Prob. 166PCh. 4 - Prob. 167PCh. 4 - Prob. 168PCh. 4 - A long 18-cm-diameter bar made of hardwood...Ch. 4 - Consider a 7.6-cm-long and 3-cm-diameter...Ch. 4 - Consider a 7.6-cm-diameter cylindrical lamb meat...Ch. 4 - Prob. 172PCh. 4 - A small chicken (k=0.45W/m.K,=0.1510-6m2/s) and...Ch. 4 - A potato may be approximated as a 5.7-cm-diameter...Ch. 4 - When water, as in a pond or lake, is heated by...Ch. 4 - A large chunk of tissue at 35C with a thermal...Ch. 4 - Prob. 177PCh. 4 - Citrus trees are very susceptible to cold weather,...
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
- Example: 0.5 kg of water per minute is heated from 20° to 40°C when passed through a tube of 2.5 cm diameter steel pipe. The pipe surface temperature is maintained at 110°C by condensing steam on its surface. Find out the length of the pipe required. The properties of water at mean temperature of 70°C are given below: p = 978 kg/m² k= 0.575 W/m. K Cp = 4200 J/kg. K v = 0.415 x 10-6 m²/secarrow_forwardA 5-m·diameter spherical tank is filled with liquid oxygen (p = 1141 kg/m cp =1.71 kJ/kg-°C) at - 184°C. It is observed that the temperature of oxygen increases to – 183°C in a 144–hour period. The average rate of heat transfer to the tank is (a) 124W (b) 185 W (c) 246 W (d) 348 W (e) 421 Warrow_forwardA pipe in a manufacturing plant is transporting superheated vapor at a mass flow rate of 0.3 kg/s. The pipe is 10 m long, has an inner diameter of 5 cm and pipe wall thickness of 6 mm. The pipe has a thermal conductivity of 17 W/m.K, and the inner pipe surface is at a uniform temperature of 120 °C. The temperature drop between the inlet and the exit of the pipe is 7 °C, and the constant pressure specific heat of vapor is 2190 J/kg.°C. If the air temperature in the manufacturing plant is 25°C, determine the heat transfer coefficient as a result if convection between the outer pipe surface and the surrounding air. T(r) = 120°C Superheated Air, 25°C r2 vapor r1 0.3 kg/s L = 10 m Tin-Tout = 7°Carrow_forward
- Mechanical servicesarrow_forwardFor heat transfer purposes, an egg can be considered to be a 5.5-cm-diameter sphere having the properties of water. An egg that is initially at 8°C is dropped into the boiling water at 86°C. The heat transfer coefficient at the surface of the egg is estimated to be 800 W/m2-K. If the egg is considered cooked when its center temperature reaches 60°C, determine how long the egg should be kept in the boiling/water. Solve this problem using analytical one-term approximation method (not the Heisler charts). The length of/time for the egg to be kept in boiling water is determined to be min.arrow_forwardA cold aluminum-canned (ε=0.60) soda is initially at a uniform temperature of 6°C. The can is 12.27 cm high with diameter of 6.60 cm. If the convection heat transfer coefficient between the can and the surrounding air at 25°C is 4.85 W/(m²-ºC), determine how long it will take for the average temperature of the soda to rise to 10ºC. Solve this problem approximately by assuming a constant average temperature of the soda during the process. For the soda use the properties of water at room temperature, p 1000 kg/m³ and Cp = 4180 J/kg-°C. Consider both convective and radiative heat transfer. =arrow_forward
- Parvinbhaiarrow_forwardA pure copper cube 3 cm on each side is placed in a 15°C stream of water.If the initial temperature of the cube is initially at 215°C, how long does it take the cube to drop to 25°C? The convective heat transfer coefficient is 80W/m2∙K. Justify any assumptions.arrow_forwardA fabricated food, in the form of small spherical pellets, is to be frozen in an air-blast freezer. The air-blast freezer is operating with air at -30°C. The initial product temperature is 25°C. The pellets have a diameter of 1.2 cm, and the density of the product is 980 kg/m³ . The initial freezing temperature is -2.5°C. The latent heat of fusion for this product is 280 kJ/kg. The thermal conductivity of the frozen product is 1.9 W/(m°C). The convective heat transfer coefficient is 50 W/(m² °C). Calculate the freezing time (h)arrow_forward
- A fabricated food, in the form of small spherical pellets, is to be frozen in an air-blast freezer. The air-blast freezer is operating with air at -30°C. The initial product temperature is 25°C. The pellets have a diameter of 1.2 cm, and the density of the product is 980 kg/m3 . The initial freezing temperature is -2.5°C. The latent heat of fusion for this product is 280 kJ/kg. The thermal conductivity of the frozen product is 1.9 W/(m°C). The convective heat transfer coefficient is 50 W/(m2°C). Calculate the freezing time.arrow_forwardOil is flowing through a 50 mm-ID and 55 mm-OD pure iron pipe at 1 m/s. It is being heated by steam outside the pipe and steam film coefficient may be taken as 11 kW/m2°C. At a particular point along the pipe, the oil is at 50°C, its density is 880 kg/m³, its viscosity is 2.1 cP, its thermal conductivity is 0.135 W/m°C and its specific heat is 2.17 J/g°C. What is the overall heat transfer coefficient at this point, based on the inside area of the pipe? If the steam temperature is 130°C, what is the heat flux at this point, based on the outside area of the pipe?arrow_forwardAn ordinary egg can be approximated as a 5.5-cm-diameter sphere whose properties are roughly k=0.6 W/m.oC and a=0.14 x 10-6 m2/s. The egg is initially at a uniform temperature of 8 oC and is dropped into boiling water at 97 oC. Taking the convection heat transfer coefficient to be h=1400 W/m2.oC, determine how long it will take for the center of the egg to reach 70oC.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 Press
Mechanics of Materials (10th Edition)Mechanical EngineeringISBN:9780134319650Author:Russell C. HibbelerPublisher:PEARSON
Thermodynamics: An Engineering ApproachMechanical EngineeringISBN:9781259822674Author:Yunus A. Cengel Dr., Michael A. BolesPublisher:McGraw-Hill Education
Control Systems EngineeringMechanical EngineeringISBN:9781118170519Author:Norman S. NisePublisher:WILEY
Mechanics of Materials (MindTap Course List)Mechanical EngineeringISBN:9781337093347Author:Barry J. Goodno, James M. GerePublisher:Cengage Learning
Engineering 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
Heat Transfer – Conduction, Convection and Radiation; Author: NG Science;https://www.youtube.com/watch?v=Me60Ti0E_rY;License: Standard youtube license