Fundamentals of Heat and Mass Transfer
Fundamentals of Heat and Mass Transfer
7th Edition
ISBN: 9780470501979
Author: Frank P. Incropera, David P. DeWitt, Theodore L. Bergman, Adrienne S. Lavine
Publisher: Wiley, John & Sons, Incorporated
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Chapter 12, Problem 12.12P

During radiant heat treatment of a thin-film material, its shape, which may be hemispherical (a) or spherical (b), is maintained by a relatively low air pressure (as in the case of a rubber balloon). Irradiation on the film is due to emission from a radiant heater of area A h = 0.0052   m 2 , which emits diffusely with an intensity of I e , h = 169 , 000 W / m 2 · s r .
Chapter 12, Problem 12.12P, During radiant heat treatment of a thin-film material, its shape, which may be hemispherical (a) or
(a) Obtain an expression for the irradiation on the film as a function of the zenith angle θ .
(b) Based on the expressions derived in part (a), which shape provides the more uniform irradiation G and hence provides better quality control for the treatment process?

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Chapter 12 Solutions

Fundamentals of Heat and Mass Transfer

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