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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Textbook Question

Chapter 12, Problem 12.126P

The exposed surface of a power amplifier for an earth satellite receiver of area 130 m m x 130mm has a diffuse, gray, opaque coating with an emissivity of 0.5. For typical amplifier operating conditions, the surface temperature is 58 ∘ C under the following environmental conditions: air temperature, T ∞ = 27 ∘ C ; sky temperature, T s k y = 20 ∘ C ; convection coefficient, 15 W/m 2 ⋅ K ; and solar irradiation, G s = 800 W/m 2 . (a) For the above conditions, determine the electrical power being generated within the amplifier. (b) It is desired to reduce the surface temperature by applying one of the diffuse coatings (A, B, C) shown as follows.
Chapter 12, Problem 12.126P, The exposed surface of a power amplifier for an earth satellite receiver of area 130mmx130mm has a
Which coating will result in the coolest surface temperature for the same amplifier operating and environmental conditions?

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Chapter 12, Problem 12.125P

Chapter 12, Problem 12.127P

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Chapter 12 Solutions

Fundamentals of Heat and Mass Transfer

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Solution Summary: The author explains that the electrical power generated within the amplifier is 4.88 W. The coating results in coolest surface temperature.

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