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
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Chapter 2, Problem 2.11P
Consider steady-state conditions for one-dimensional conduction in a plane wall having a thermal conductivity
Determine the heat flux and the unknown quantity for each case and sketch the temperature distribution, indicating the direction of the heat flux.
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Students have asked these similar questions
(A) Consider a plane wall of thickness L and thermal conductivity k. The two sides of the
wall are maintained at constant temperatures of T1 and T2 respectively. Show that the
temperature distribution through the wall is represented as
Т, - Т,
T =
- x +
x+T|
L
Assume one dimensional steady state heat conduction
Problems
within the wall is T(x) = a(L- ) +b where
a = 10°C/m2 and b 30°C, what is the thermal con-
ductivity of the wall? What is the value of the convec-
tion heat transfer coefficient, h?
2.11 Consider steady-state conditions for one-dimensional
conduction in a plane wall having a thermal conductiv-
ity k 50 W/m K and a thickness L = 0.25 m, with no
internal heat generation.
2.
T2
T1
L
Determine the heat flux and the unknown quantity for
each case and sketch the temperature distribution, indi-
cating the direction of the heat flux.
2
Case
TC)
dTldx (K/m)
T2(°C)
1
50
-20
2
-30
- 10
3
70
160
4
40
-80
5
30
200
Q1: Consider one-dimensional conduction in a plane composite wall (Im x Im) as shown in
the figure below. The outer surfaces are exposed to a fluid at 25°C and a convection heat transfer
coefficient of 1000 W/m K. The middle wall B experiences uniform heat generation dg, while
there is no generation in walls A and C. The temperatures at the interfaces are T=261°C and T;
-211°C. Assuming negligible contact resistance at the interfaces:
A) Determine the outside surface temperature of walls A and C?
B) Compute the value of dg?
(20 M)
A
B.
ーム
k= 25 Wim-K
A = 50 W/m-K
L = 30 mm
Le= 30 mm
L = 20 mm
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Chapter 2 Solutions
Introduction to Heat Transfer
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