The directional total emissivity of nonmetallic materials may be approximated as , n, cos , where n, is the normal emissivity Show that the total hemispherical emissivity for such materials is 2 3 of the normal emissivity ...

KNOWN The total directional emissivity of nonmetallic materials may be approximated as En cos ...

The directional total emissivity of nonmetallic materials may be approximated as , = n, cos , where

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The directional total emissivity of nonmetallic materials may be approximated as εθ, = εn, cos θ, where εn, is the normal emissivity. Show that the total hemispherical emissivity for such materials is 2/3 of the normal emissivity.

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Fundamentals of Heat and Mass Transfer

ISBN: 978-0471457282

6th Edition

Authors: Incropera, Dewitt, Bergman, Lavine

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Question Posted: Mar 02, 2011 12:59 AM

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The directional total emissivity of nonmetallic materials may be approximated as , = n, cos , where

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Fundamentals of Heat and Mass Transfer

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