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 1, Problem 1.11P
The heat flux that is applied to one face of a plane wall is
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A thermal system having a cylindrical form contains a sequence of cylindrical layers is used to cool hot gases. The thermal properties of the
system materials are as follows : k = 231 W/m.K, c = 1033 J/kg.K and the density = 2702 kg/m^3. The gases to be cooled has a temperature
equals to 500 C. Determine the temperature of the system that corresponds to 10 % of the maximum possible heat transfer between the
gas and the system. Consider that the system has a characteristic length equals to 0.03 m. The heat convective coefficient is equal to 50
W/m^2.K. The initial temperature of the system is equal to 20 C.
Select one:
О а. 370 К
O b. 489 K
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=
Consider a large plane wall of thickness L=0.3 m, thermal conductivity k = 2.5 W/m.K,
and surface area A = 12 m². The left side of the wall at x=0 is subjected to a net heat
flux of ɖo = 700 W/m² while the temperature at that surface is measured to be T₁ =
80°C. Assuming constant thermal conductivity and no heat generation in the wall, (a)
express the differential equation and the boundary equations for steady one-
dimensional heat conduction through the wall, (b) obtain a relation for the variation of
the temperature in the wall by solving the differential equation, and (c) evaluate the
temperature of the right surface of the wall at x=L.
Ti
до
L
X
The temperature distribution across a wall 0.3 m thick at a certain instant of time is T(x) = a+ b+cx?, where T is
in degrees Celsius and x is in meters, a = 200°C,b = -200°, and c =
conductivity of 1 W /m · K.
30°C/m² . The wall has a thermal
(a) On a unit surface area basis, determine the rate of heat transfer into and out of the wall and the rate of change of
energy stored by the wall.
(b) If the cold surface is exposed to a fluid at 100°C, what is the convection coefficient?
k=1W/m•k
T(x) =200-200x + 30x²
200°C-
ĖST
142.7°C
q"out
| Fluid
Too = 100°C,h
9"in
|L-0.3m
Chapter 1 Solutions
Introduction to Heat Transfer
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