Fundamentals of Thermal-Fluid Sciences
5th Edition
ISBN: 9780078027680
Author: Yunus A. Cengel Dr., Robert H. Turner, John M. Cimbala
Publisher: McGraw-Hill Education
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Chapter 17, Problem 123RQ
(a)
To determine
The thermal resistance.
(b)
To determine
The steady rate of heat transfer.
(c)
To determine
The temperature difference across the insulation layer.
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Chapter 17 Solutions
Fundamentals of Thermal-Fluid Sciences
Ch. 17 - Prob. 1PCh. 17 - Consider heat conduction through a plane wall....Ch. 17 - What does the thermal resistance of a medium...Ch. 17 - Can we define the convection resistance for a unit...Ch. 17 - Consider steady heat transfer through the wall of...Ch. 17 - How is the combined heat transfer coefficient...Ch. 17 - Why are the convection and the radiation...Ch. 17 - Consider steady one-dimensional heat transfer...Ch. 17 - Someone comments that a microwave oven can be...Ch. 17 - Consider two cold canned drinks, one wrapped in a...
Ch. 17 - Consider a surface of area A at which the...Ch. 17 - How does the thermal resistance network associated...Ch. 17 - Consider steady one-dimensional heat transfer...Ch. 17 - Consider a window glass consisting of two...Ch. 17 - Prob. 15PCh. 17 - Prob. 16PCh. 17 - Prob. 17PCh. 17 - Prob. 18PCh. 17 - Prob. 19PCh. 17 - Consider a power transistor that dissipates 0.2 W...Ch. 17 - A 1.0 m × 1.5 m double-pane window consists of two...Ch. 17 - Consider a 1.2-m-high and 2-m-wide glass window...Ch. 17 - Prob. 23PCh. 17 - Prob. 24PCh. 17 - Prob. 26PCh. 17 - Prob. 27PCh. 17 - Prob. 28PCh. 17 - Prob. 29PCh. 17 - Prob. 30PCh. 17 - A 2-m × 1.5-m section of wall of an industrial...Ch. 17 - The wall of a refrigerator is constructed of...Ch. 17 - Prob. 34PCh. 17 - Prob. 35PCh. 17 - Prob. 36PCh. 17 - What is thermal contact resistance? How is it...Ch. 17 - Will the thermal contact resistance be greater for...Ch. 17 - Explain how the thermal contact resistance can be...Ch. 17 - A wall consists of two layers of insulation...Ch. 17 - A plate consists of two thin metal layers pressed...Ch. 17 - Consider two surfaces pressed against each other....Ch. 17 - Prob. 43PCh. 17 - Prob. 44PCh. 17 - Prob. 45PCh. 17 - Prob. 46PCh. 17 - Prob. 47PCh. 17 - Prob. 48PCh. 17 - Prob. 49PCh. 17 - Prob. 50PCh. 17 - Prob. 51PCh. 17 - Prob. 52PCh. 17 - Prob. 53PCh. 17 - When plotting the thermal resistance network...Ch. 17 - Prob. 55PCh. 17 - Prob. 56PCh. 17 - Prob. 57PCh. 17 - A typical section of a building wall is shown in...Ch. 17 - Prob. 59PCh. 17 - Prob. 61PCh. 17 - Prob. 62PCh. 17 - Prob. 63PCh. 17 - In an experiment to measure convection heat...Ch. 17 - What is an infinitely long cylinder? When is it...Ch. 17 - Can the thermal resistance concept be used for a...Ch. 17 - Consider a short cylinder whose top and bottom...Ch. 17 - Prob. 68PCh. 17 - 50-m-long section of a steam pipe whose outer...Ch. 17 - Superheated steam at an average temperature 200°C...Ch. 17 - Steam exiting the turbine of a steam power plant...Ch. 17 - Repeat Prob. 17–72E, assuming that a 0.01-in-thick...Ch. 17 - A 2.2-mm-diameter and 10-m-long electric wire is...Ch. 17 - Prob. 76PCh. 17 - Chilled water enters a thin-shelled 5-cm-diameter,...Ch. 17 - Steam at 450°F is flowing through a steel pipe (k...Ch. 17 - Prob. 79PCh. 17 - Prob. 80PCh. 17 - An 8-m-internal-diameter spherical tank made of...Ch. 17 - What is the critical radius of insulation? How is...Ch. 17 - Consider an insulated pipe exposed to the...Ch. 17 - A pipe is insulated to reduce the heat loss from...Ch. 17 - Prob. 86PCh. 17 - Prob. 87PCh. 17 - A 0.083-in-diameter electrical wire at 90°F is...Ch. 17 - Prob. 89PCh. 17 - Prob. 90PCh. 17 - Prob. 92PCh. 17 - What is the reason for the widespread use of fins...Ch. 17 - What is the difference between the fin...Ch. 17 - The fins attached to a surface are determined to...Ch. 17 - Explain how the fins enhance heat transfer from a...Ch. 17 - How does the overall effectiveness of a finned...Ch. 17 - Hot water is to be cooled as it flows through the...Ch. 17 - Consider two finned surfaces that are identical...Ch. 17 - The heat transfer surface area of a fin is equal...Ch. 17 - Prob. 101PCh. 17 - Prob. 102PCh. 17 - Two plate fins of constant rectangular cross...Ch. 17 - Two finned surfaces are identical, except that the...Ch. 17 - A 4-mm-diameter and 10-cm-long aluminum fin (k =...Ch. 17 - Consider a very long rectangular fin attached to a...Ch. 17 - Consider a stainless steel spoon (k = 8.7...Ch. 17 - A DC motor delivers mechanical power to a rotating...Ch. 17 - A plane wall with surface temperature of 350°C is...Ch. 17 - Prob. 111PCh. 17 - Steam in a heating system flows through tubes...Ch. 17 - Prob. 113PCh. 17 - A hot surface at 100°C is to be cooled by...Ch. 17 - Prob. 116PCh. 17 - A 40-W power transistor is to be cooled by...Ch. 17 - Prob. 118PCh. 17 - Prob. 119RQCh. 17 - Cold conditioned air at 12°C is flowing inside a...Ch. 17 - Prob. 121RQCh. 17 - Prob. 122RQCh. 17 - Prob. 123RQCh. 17 - Prob. 124RQCh. 17 - Prob. 125RQCh. 17 - Prob. 126RQCh. 17 - Prob. 127RQCh. 17 - Prob. 128RQCh. 17 - Prob. 129RQCh. 17 - Prob. 130RQCh. 17 - Prob. 131RQ
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