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 2.35P
To determine
The heat diffusion equation for cylindrical coordinates.
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Students have asked these similar questions
b) Using the heat diffusion equation which you have derived in part (a).
Let consider a one-dimensional plane wall that separate of two fluids which
is illustrated in Figure lb with constant properties (e.g. thermal
conductivity, k) and uniform internal generation (e.g. no heat generation)
and steady state condition (e.g no change in the amount of energy storage)
i) Find the expression of temperature distribution, T(x)
ii) and the expression of heat flow, q
Ts.
Cold fluid
T2 h2
Hot fluid
T2
T1. h
Lox
x = L
Figure 1b
Nuclear fuel rods. A typical nuclear fuel rod contains circular uranium oxide (UO2)
fuel pellets 10 mm in diameter and 5-mm thick stacked in a column to a length of
4 m inside a thin zirconium alloy tube, as shown below. The pellets generate heat
uniformly throughout their volume due to nuclear fission, with a power density a
(i.e., the heat power produced per unit volume of the pellet) that depends on their
235U enrichment. This heats up the water in the reactor to produce steam to drive
the turbine. Assuming that the rim of the fuel pellet is maintained at a constant
temperature Trim due to water cooling, show that the steady-state temperature
profile T(r), where r is the radial distance from the centre of the pellet and fuel rod,
4.
P(R? -r²;
is given by: T(r) = Tim +
4k
where k is the thermal conductivity of the
pellet and R is its radius.
partial stacked column
of fuel pellets in rod
2. Heat transfer coefficients can be difficult to measure, particularly for situations involving
fast-moving fluids. In some cases however, the magnitude of the heat transfer
coefficients can be estimated to a sufficient degree to enable further analysis of the larger
problem.
In a situation such as that described in the preceding paragraph, heat transfer occurs
through the planar wall shown in the figure below. Two thermal situations are to be
considered. In case I, the temperature of the fluid to the left of the wall is 130.5 °F and
the fluid on the right is at 71.3 °F. Both sides of the planar wall are washed by fast-
moving water. The exact values of the convective heat transfer coefficients are unknown.
The heat flux through the wall is measured to be 42.6 Btu/hr-ft².
2 inches
Tfl
h₁
T₁
T₂
T₁²
11₂
Chapter 2 Solutions
Introduction to Heat Transfer
Ch. 2 - Assume steady-state, one-dimensional heat...Ch. 2 - Assume steady-state, one-dimensional conduction in...Ch. 2 - A hot water pipe with outside radius r1 has a...Ch. 2 - A spherical shell with inner radius r1 and outer...Ch. 2 - Assume steady-state, one-dimensional heat...Ch. 2 - A composite rod consists of two different...Ch. 2 - A solid, truncated cone serves as a support for a...Ch. 2 - To determine the effect of the temperature...Ch. 2 - Prob. 2.9PCh. 2 - A one-dimensional plane wall of thickness 2L=100mm...
Ch. 2 - Consider steady-state conditions for...Ch. 2 - Consider a plane wall 100 mm thick and of thermal...Ch. 2 - Prob. 2.13PCh. 2 - In the two-dimensional body illustrated, the...Ch. 2 - Consider the geometry of Problem 2.14 for the case...Ch. 2 - Steady-state, one-dimensional conduction occurs in...Ch. 2 - Prob. 2.17PCh. 2 - Prob. 2.18PCh. 2 - Consider a 300mm300mm window in an aircraft. For a...Ch. 2 - Prob. 2.20PCh. 2 - Use IHT to perform the following tasks. Graph the...Ch. 2 - Calculate the thermal conductivity of air,...Ch. 2 - A method for determining the thermal conductivity...Ch. 2 - Prob. 2.24PCh. 2 - Prob. 2.25PCh. 2 - At a given instant of time, the temperature...Ch. 2 - Prob. 2.27PCh. 2 - Uniform internal heat generation at q.=5107W/m3 is...Ch. 2 - Prob. 2.29PCh. 2 - The steady-state temperature distribution in a...Ch. 2 - The temperature distribution across a wall 0.3 m...Ch. 2 - Prob. 2.32PCh. 2 - Prob. 2.33PCh. 2 - Prob. 2.34PCh. 2 - Prob. 2.35PCh. 2 - Prob. 2.36PCh. 2 - Prob. 2.37PCh. 2 - One-dimensional, steady-state conduction with no...Ch. 2 - One-dimensional, steady-state conduction with no...Ch. 2 - The steady-state temperature distribution in a...Ch. 2 - One-dimensional, steady-state conduction with no...Ch. 2 - Prob. 2.42PCh. 2 - Prob. 2.43PCh. 2 - Prob. 2.44PCh. 2 - Beginning with a differential control volume in...Ch. 2 - A steam pipe is wrapped with insulation of inner...Ch. 2 - Prob. 2.47PCh. 2 - Prob. 2.48PCh. 2 - Two-dimensional, steady-state conduction occurs in...Ch. 2 - Prob. 2.50PCh. 2 - Prob. 2.51PCh. 2 - A chemically reacting mixture is stored in a...Ch. 2 - A thin electrical heater dissipating 4000W/m2 is...Ch. 2 - The one-dimensional system of mass M with constant...Ch. 2 - Consider a one-dimensional plane wall of thickness...Ch. 2 - A large plate of thickness 2L is at a uniform...Ch. 2 - Prob. 2.57PCh. 2 - Prob. 2.58PCh. 2 - A plane wall has constant properties, no internal...Ch. 2 - A plane wall with constant properties is initially...Ch. 2 - Consider the conditions associated with Problem...Ch. 2 - Prob. 2.62PCh. 2 - A spherical particle of radius r1 experiences...Ch. 2 - Prob. 2.64PCh. 2 - A plane wall of thickness L=0.1m experiences...Ch. 2 - Prob. 2.66PCh. 2 - A composite one-dimensional plane wall is of...Ch. 2 - Prob. 2.68PCh. 2 - The steady-state temperature distribution in a...
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