Fundamentals of Heat and Mass Transfer
Fundamentals of Heat and Mass Transfer
7th Edition
ISBN: 9780470917855
Author: Bergman, Theodore L./
Publisher: John Wiley & Sons Inc
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Chapter 13, Problem 13.59P

Heat transfer by radiation occurs between two large parallel plates, which are maintained at temperatures T1and T2, with T 1 > T 2 . To reduce the rate of heat transfer between the plates, it is proposed that they be separated by a thin shield that has different emissivities on opposite surfaces. In particular, one surface has the emissivity ε s < 0.5 , while the opposite surface has an emissivity of 2 ε s .
(a) How should the shield be oriented to provide the larger reduction in heat transfer between the plates? That is, should the surface of emissivity ε s or that of emissivity 2 ε s be oriented toward the plate at T1?
(b) What orientation will result in the larger value of the shield temperature Ts?

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Chapter 13 Solutions

Fundamentals of Heat and Mass Transfer

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