Introduction to Heat Transfer
6th Edition
ISBN: 9780470501962
Author: Frank P. Incropera, David P. DeWitt, Theodore L. Bergman, Adrienne S. Lavine
Publisher: Wiley, John & Sons, Incorporated
expand_more
expand_more
format_list_bulleted
Videos
Textbook Question
Chapter 1, Problem 1.20P
A wall has inner and outer surface temperatures of 16 and
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solution
Students have asked these similar questions
A flat wall is exposed to an environmental temperature of 38 oC. The wall is covered with a layer of insulation 2.5 cm thick whose thermal conductivity is 1.4 W/m oC, and the temperature of the wall on the inside of the insulation is 315 oC. The wall loses heat to the environment by convection. Compute the value of the convection heat-transfer coefficient that must be maintained on the outer surface of the insulation to ensure that the outer-surface temperature does not exceed 41oC.
The building is in an environment of 30 ° C. The walls are covered with an insulating layer of 4 cm thickness whose thermal conductivity is 1.8 W / (m K), and the temperature of the inner wall of the insulation is 320 ° C. Wall heat loss to the environment occurs by convection. Calculate the convection heat transfer coefficient value on the outer surface of the insulation to ensure that the outer surface temperature does not exceed 40 ° C.
Convection coefficient = AnswerW / m² ° C.
The inside surface of an insulation layer is maintained at 350oC and the outside surface dissipates heat by convection and radiation to air and wall, respectively. The temperatures of air and wall are 15 oC. The insulation layer has a thickness of 10 cm and a thermal conductivity of 15 W/m.K. What is the value of the heat transfer coefficient at the outside surface of the layer, if the temperature at the outside surface should not exceed 225 oC? (The emissivity and the width of the surface are 0.3 and 1 m., respectively. =5.67x10-8 W/m2K4).
Chapter 1 Solutions
Introduction to Heat Transfer
Ch. 1 - The thermal conductivity of a sheet of rigid,...Ch. 1 - The heat flux that is applied to the left face of...Ch. 1 - A concrete wall, which has a surface area of 20m2...Ch. 1 - The concrete slab of a basement is 11 m long, 8 m...Ch. 1 - Consider Figure 1.3. The heat flux in the...Ch. 1 - Prob. 1.6PCh. 1 - The inner and outer surface temperatures of a...Ch. 1 - A thermodynamic analysis of a proposed Brayton...Ch. 1 - A glass window of width W=1m and height H=2m is 5...Ch. 1 - Prob. 1.10P
Ch. 1 - The heat flux that is applied to one face of a...Ch. 1 - Prob. 1.12PCh. 1 - Prob. 1.13PCh. 1 - Prob. 1.14PCh. 1 - The 5-mm-thick bottom of a 200-mm-diameter pan may...Ch. 1 - Prob. 1.16PCh. 1 - For a boiling process such as shown in Figure...Ch. 1 - You've experienced convection cooling if you've...Ch. 1 - Prob. 1.19PCh. 1 - A wall has inner and outer surface temperatures of...Ch. 1 - An electric resistance heater is embedded in a...Ch. 1 - Prob. 1.22PCh. 1 - A transmission case measures W=0.30m on a side and...Ch. 1 - Prob. 1.24PCh. 1 - A common procedure for measuring the velocity of...Ch. 1 - Prob. 1.26PCh. 1 - Prob. 1.27PCh. 1 - Prob. 1.28PCh. 1 - Prob. 1.29PCh. 1 - Prob. 1.30PCh. 1 - Prob. 1.31PCh. 1 - Prob. 1.32PCh. 1 - Prob. 1.33PCh. 1 - Prob. 1.34PCh. 1 - An electrical resistor is connected to a battery,...Ch. 1 - Pressurized water pin=10bar,Tin=110C enters the...Ch. 1 - Consider the tube and inlet conditions of Problem...Ch. 1 - An internally reversible refrigerator has a...Ch. 1 - A household refrigerator operates with cold- and...Ch. 1 - Chips of width L=15mm on a side are mounted to a...Ch. 1 - Consider the transmission case of Problem 1.23,...Ch. 1 - One method for growing thin silicon sheets for...Ch. 1 - Heat is transferred by radiation and convection...Ch. 1 - Radioactive wastes are packed in a long,...Ch. 1 - An aluminum plate 4 mm thick is mounted in a...Ch. 1 - A blood warmer is to be used during the...Ch. 1 - Consider a carton of milk that is refrigerated at...Ch. 1 - The energy consumption associated with a home...Ch. 1 - Liquid oxygen, which hems a boiling point of 90 K...Ch. 1 - The emissivity of galvanized steel sheet, a common...Ch. 1 - Three electric resistance heaters of length...Ch. 1 - A hair dryer may be idealized as a circular duct...Ch. 1 - In one stage of an annealing process, 304...Ch. 1 - Convection ovens operate on the principle of...Ch. 1 - Annealing, an important step in semiconductor...Ch. 1 - In the thermal processing of semiconductor...Ch. 1 - A furnace for processing semiconductor materials...Ch. 1 - Single fuel cells such as the one of Example 1.5...Ch. 1 - Prob. 1.59PCh. 1 - Prob. 1.60PCh. 1 - Prob. 1.61PCh. 1 - A small sphere of reference-grade iron with a...Ch. 1 - A 50mm45mm20mm cell phone charger has a surface...Ch. 1 - A spherical, stainless steel (AISI 302) canister...Ch. 1 - Prob. 1.65PCh. 1 - Prob. 1.66PCh. 1 - A photovoltaic panel of dimension 2m4m is...Ch. 1 - Following the hot vacuum forming of a paper-pulp...Ch. 1 - Prob. 1.69PCh. 1 - Prob. 1.70PCh. 1 - Prob. 1.71PCh. 1 - The roof of a car in a parking lot absorbs a solar...Ch. 1 - Prob. 1.73PCh. 1 - Prob. 1.74PCh. 1 - Consider Problem 1.1. If the exposed cold surface...Ch. 1 - Prob. 1.76PCh. 1 - Prob. 1.77PCh. 1 - A thin electrical heating element provides a...Ch. 1 - Prob. 1.79PCh. 1 - Prob. 1.80PCh. 1 - Prob. 1.81PCh. 1 - The curing process of Example 1.9 involves...Ch. 1 - The diameter and surface emissivity of an...Ch. 1 - Bus bars proposed for use in a power transmission...Ch. 1 - A solar flux of 700W/m2 is incident on a...Ch. 1 - In considering the following problems involving...
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
- 3.16 A large, 2.54-cm.-thick copper plate is placed between two air streams. The heat transfer coefficient on one side is and on the other side is . If the temperature of both streams is suddenly changed from 38°C to 93°C, determine how long it takes for the copper plate to reach a temperature of 82°C.arrow_forward1.19 A cryogenic fluid is stored in a 0.3-m-diameter spherical container is still air. If the convection heat transfer coefficient between the outer surface of the container and the air is 6.8 , the temperature of the air is 27°C, and the temperature of the surface of the sphere is –183°C, determine the rate of heat transfer by convection.arrow_forwardA cooling system is to be designed for a food storage warehouse for keeping perishable foods cool prior to transportation to grocery stores. The warehouse has an effective surface area of 1860 m2 exposed to an ambient air temperature of 32C. The warehouse wall insulation (k=0.17W/(mK)) is 7.5 cm thick. Determine the rate at which heat must be removed (W) from the warehouse to maintain the food at 4C.arrow_forward
- 1.60 Two electric resistance heaters with a 20 cm length and a 2 cm diameter are inserted into a well-insulated 40-L tank of water that is initially at 300 K. If each heater dissipates 500 W, what is the time required for bringing the water temperature in the tank to 340 K? State your assumption for your analysis.arrow_forward1.39 On a cold winter day, the outside wall of a home is exposed to an air temperature of when the inside temperature of the room is at . As a result of this temperature gradient, there is heat loss through the wall to the outside. Consider the convective heat transfer coefficients for the air inside the room and at the outside wall surface to be, respectively, 12.0 and . If the composite room wall is modeled as a plane wall with a thermal resistance per unit area of , determine the temperature at the outer surface of the wall as well as the rate of heat flow through the wall per unit area. If the homeowner were to consider using a fiberglass insulation layer on the inside wall surface for reducing this heat loss by 50%, what is the required thickness of this layer and the outside wall temperature for this case?arrow_forwardThe heat transfer rate from hot air by convection at 100C flowing over one side of a flat plate with dimensions 0.1m0.5m is determined to be 125 W when the surface of the plate is kept at 30C. What is the average convection heat transfer coefficient between the plate and the air?arrow_forward
- A slab 0.2 m thick with thermal conductivity of 45 W/mK receives heat from a furnace at 500 K both by convection and radiation. The convection coefficient has a value of 50 W/m2K. The surface temperature is 400 K on this side. The heat is transferred to surroundings at T∞2 both by convection and radiation. The convection coefficient on this side being 60 W/m2K. Determine the surrounding temperature. Assume F = 1 for radiationarrow_forwardQUESTION 3: Warm air is blown over the inner surface of the windshield of an automobile to defrost ice accumulated on the outer surface. The windshield has a thickness of 5 mm and thermal conductivity of 1.4 W/m-K. The outside ambient temperature is -10°C and the convection heat transfer coefficient is 200 W/m²-K, while the ambient temperature inside the automobile is 25°C. Determine the value of the convection heat transfer coefficient for the warm air blowing over the inner surface of the windshield necessary to cause the accumulated ice to begin melting.arrow_forwardA large plate of aluminum 5.0 cm thick and initially at 200◦C is suddenly exposed to the convection environment of 70◦C with heat-transfer coefficient of 525 W/m2 · ◦C. Calculate the temperature at a depth of 1.25 cm from one of the faces1 min after the plate has been exposed to the environment. How much energy has been removed per unit area from the plate in this time?arrow_forward
- A metal cube of 0.1 m sides is being cooled down uniformly from 300°C to 30°C by placing it in cold water at 10°C. The convection coefficient of water around the cube is 40 W/m².K. The properties of the cube material are as follows - thermal conductivity: 137 W/m-K, density: 1600 kg/m³; specific heat: 800 J/kg.K. Neglect radiation. Find the time required for coo cooling. 1426-2arrow_forwardThe rate of heat flow through a hallow sphere of inner radius 0.25 m and outer radius 0.35m, whose thermal conductivity is 5 W/mK, maintained at temperatures of 400°C and 300°C respectively equal toarrow_forwardSteam at 180 0C flows in a circular pipe, which is composed of 3 different materials (A, B and C). The pipe is located in a room at 20 0C. Convection heat transfer coefficient between the steam and the inner surface of the wall is 27.777 W/m2K. Convection and radiation heat transfer coefficient between the outer surface of the pipe and the air are 7 and 3 W/m2K, respectively. Thermal resistances of the layers are RA=0.02 0C/W, RB=0.03 0C/W and RC=0.08 0C/W. The inner and the outer surface area of the pipe are A1=1.8 and A4=2 m2, respectively. What is the temperature at interface 3? a. 142 0C b. 124 0C c. 138 0C d. 134 0C e. 130 0Carrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
Principles of Heat Transfer (Activate Learning wi...Mechanical EngineeringISBN:9781305387102Author:Kreith, Frank; Manglik, Raj M.Publisher:Cengage Learning
Principles of Heat Transfer (Activate Learning wi...
Mechanical Engineering
ISBN:9781305387102
Author:Kreith, Frank; Manglik, Raj M.
Publisher:Cengage Learning
Heat Transfer – Conduction, Convection and Radiation; Author: NG Science;https://www.youtube.com/watch?v=Me60Ti0E_rY;License: Standard youtube license