Fundamentals of Heat and Mass Transfer
7th Edition
ISBN: 9780470917855
Author: Bergman, Theodore L./
Publisher: John Wiley & Sons Inc
expand_more
expand_more
format_list_bulleted
Videos
Textbook Question
Chapter 1, Problem 1.20P
A wall has inner and outer surface temperatures of 16and 6°C, respectively. The interior and exterior air temperatures are 20 and 5°C, respectively. The inner andouter convection heal transfer coefficients are 5 and
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solution
Students have asked these similar questions
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).
The length of one side of a cube-shaped freezer cabinet is 11.8 m. your closetits base is perfectly insulated against heat transfer and the inner surface temperature is –5 °C, the outer surface temperatureand it is 59°C. To ensure that the thermal load of the cabinet is not less than 0.59 kWThe thickness of the styrofoam foam insulation (k=0.03 W/mK) to be applied to the upper and side surfacesWhat should be less?
Location of maximum temperature within the plate from its left face
Chapter 1 Solutions
Fundamentals of Heat and Mass 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 in long. 8...Ch. 1 - Consider Figure 1.3. The heat flux in the...Ch. 1 - The heal flux through a wood slab 50 mm thick,...Ch. 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 - A freezer compartment consists of a cubical cavity...
Ch. 1 - The heat flux that is applied to one face of a...Ch. 1 - An inexpensive food and beverage container is...Ch. 1 - What is the thickness required of a masonry wall...Ch. 1 - A wall is made from an inhomogeneous...Ch. 1 - The 5-mm-thick bottom of a 200-mm-diameter panmay...Ch. 1 - A square silicon chip (k=150W/mK) is of width...Ch. 1 - For a boiling process such as shown in Figure 1.5...Ch. 1 - You’ve experienced convection cooling if you’ve...Ch. 1 - Air at 40°C flows over a long, 25-mm-diameter...Ch. 1 - A wall has inner and outer surface temperatures of...Ch. 1 - An electric resistance heater is embedded in a...Ch. 1 - The free convection heat transfer coefficient on a...Ch. 1 - A transmission case measures W=0.30m on a sideand...Ch. 1 - A cartridge electrical heater is shaped as a...Ch. 1 - A common procedure for measuring the velocity of...Ch. 1 - A square isothermal chip is of width w=5mm on...Ch. 1 - The temperature controller for a clothes dryer...Ch. 1 - An overhead 25-m-long, uninsulated industrial...Ch. 1 - Under conditions for which the same room...Ch. 1 - A spherical interplanetary probe of 0.5-m diameter...Ch. 1 - An instrumentation package has a spherical outer...Ch. 1 - Consider the conditions of Problem 1.22. However,...Ch. 1 - If TsTsur in Equation 1.9, the radiation heat...Ch. 1 - A vacuum system, as used ¡n sputtering...Ch. 1 - An electrical resistor is connected to a battery,...Ch. 1 - Pressurized water (pin=10bar,Tin=110C) enters...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-...Ch. 1 - Chips of width L=15mm on a side are mounted to...Ch. 1 - Consider the transmission case of Problem 1...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 - Prob. 1.48PCh. 1 - Liquid oxygen, which has a boiling into of 90 K...Ch. 1 - The emissivity of galvanized steel sheet, a...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 ¡n semiconductor...Ch. 1 - In the thermal processing of semiconductor...Ch. 1 - A furnace tor processing semiconductor materials...Ch. 1 - Prob. 1.58PCh. 1 - Consider the wind turbine of Example 1.3. To...Ch. 1 - Consider the conducting rod of Example 1.4...Ch. 1 - A long bus bar (cylindrical rod used for making...Ch. 1 - A 50mm45mm20mm cell phone chargerhas a surface...Ch. 1 - A spherical, stainless steel (AISI 302) canister...Ch. 1 - A freezer compartment is covered with a...Ch. 1 - A vertical slab of Wood’s metal is joined to a...Ch. 1 - A photovoltaic panel of dimension 2m4m isinstalled...Ch. 1 - Following the hot vacuum forming of a...Ch. 1 - Prob. 1.69PCh. 1 - A computer consists of an array of five printed...Ch. 1 - Prob. 1.71PCh. 1 - The roof of a car in a parking lot absorbs a solar...Ch. 1 - Consider the conditions of Problem 1.22,but the...Ch. 1 - Most of the energy we consume as food ¡s converted...Ch. 1 - Prob. 1.75PCh. 1 - The wall of an oven used to cure plastic parts is...Ch. 1 - An experiment to determine the convection...Ch. 1 - A thin electrical heating element provides a...Ch. 1 - A rectangular forced air healing duct is suspended...Ch. 1 - Consider the steam pipe of Example 1.2. The...Ch. 1 - During its manufacture, plate glass at 600°C is...Ch. 1 - The curing press of Example 1.9 involves exposure...Ch. 1 - The diameter and surface emissivity of an...Ch. 1 - Prob. 1.84PCh. 1 - A solar flux of 700W/m2K 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_forward2.38 The addition of aluminum fins has been suggested to increase the rate of heat dissipation from one side of an electronic device 1 m wide and 1 m tall. The fins are to be rectangular in cross section, 2.5 cm long and 0.25 cm thick, as shown in the figure. There are to be 100 fins per meter. The convection heat transfer coefficient, both for the wall and the fins, is estimated to be K. With this information determine the percent increase in the rate of heat transfer of the finned wall compared to the bare wall.arrow_forward2.9 In a large chemical factory, hot gases at 2273 K are cooled by a liquid at 373 K with gas-side and liquid-side convection heat transfer coefficients of 50 and , respectively. The wall that separates the gas and liquid streams is composed of a 2-cm thick oxide layer on the gas side and a 4-cm thick slab of stainless steel on the liquid side. There is a contact resistance between the oxide layer and the steel of . Determine the rate of heat loss from hot gases through the composite wall to the liquid.arrow_forward
- The air-conditioning system in a Chevrolet van for use in desert climates is to be sized. The system is to maintain an interior temperature of 20C when the van travels at 100 km/h through dry air at 30C at night. If the top of the van is idealized as a flat plate 6 m long and 2 m wide and the sides as flat plates 3 m tall and 6 m long, estimate the rate at which heat must be removed from the interior to maintain the specifiedarrow_forwardThe interior wall of a large, commercial walk-in type meat freezer is covered under normal operating conditions with a 2-cm thick layer of ice. One day, a power outage cuts electricity to the refrigeration system of the freezer. Estimate the time required to melt this layer of ice if it has a mass density of 700kg/m3 and a latent heat of fusion of 334 kJ/kg. Consider the air temperature inside the freezer to be 20C with a heat transfer coefficient of 2W/m2K for convection from the freezer surface to air, and clearly state the assumptions made in your calculations.arrow_forward3.10 A spherical shell satellite (3-m-OD, 1.25-cm-thick stainless steel walls) re-enters the atmosphere from outer space. If its original temperature is 38°C, the effective average temperature of the atmosphere is 1093°C, and the effective heat transfer coefficient is , estimate the temperature of the shell after reentry, assuming the time of reentry is 10 min and the interior of the shell is evacuated.arrow_forward
- 1.19 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_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_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
- 1.1 On a cold winter day, the outer surface of a 0.2-m-thick concrete wall of a warehouse is exposed to temperature of –5°C, while the inner surface is kept at 20°C. The thermal conductivity of the concrete is 1.2 W/m K. Determine the heat loss through the wall, which is 10-m long and 3-m high. Problem 1.1arrow_forward2 A vertical furnace wall is made up of an inner of firebrick 20 cm thick followed by insulating brick 15 cm thick and an outer wall of steel 1 cm thick. The surface temperature of the wall adjacent to the combustion chamber is 1,200°C while that the outer surface of steel is 50°C. The thermal conductivities of the wall material in W/m-K are: firebrick, 10; insulating brick, 0.26; and steel, 45. Neglecting the film resistances and contact resistance joints, determine the heat loss per sq. m. of wall area.arrow_forwardA spherical ball (15 cm in diameter) with a density of 1000 kg/m³, specific heat capacity of 4180 J/kg-K and thermal conductivity of 0.62 W/m-K is removed from an oven at a uniform temperature of 150 °C. The ball is then left to cool down in steady air at 10 °C. Calculate the heat transfer coefficient for this process and the time for the surface of the ball to drop to 20 °C. Use the following equation to solve this problem (characteristic dimension of the sphere is the diameter). 0.589 . Ra* Nu = 2+ 0.469 16 Prarrow_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