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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Radiation can be described as the energy in the form of a particular matter or electromagnetic waves traveling in the air and can be in the form of light, sound, and heat. Radiation can be detected through special instruments like X-rays. The radiation f…

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Textbook Question

Chapter 13, Problem 13.137P

A grain dryer consists of a long semicircular duct of radius R = 1 m . One-half of the base surface consists of an electrically heated plate of emissivity ε p = 0.8 , while the other half supports the grain to be dried, which has an emissivity of ε g = 0.9 . In a batch drying process for which the temperature of the grain is
T g = 330 K , 2.50 kg of Water are to be removed per meter of duct length over a 1-h period.
Chapter 13, Problem 13.137P, A grain dryer consists of a long semicircular duct of radius R=1m . One-half of the base surface
(a) Neglecting convection heat transfer, determine the required temperature T_pof the heater plate.
(b) If the water vapor is swept from the duct by the flow of dry air, what convection mass transfer coefficient h_mmust be maintained by the flow?
(c) If the air is at 300 K, is the assumption of negligible convection justified?

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Chapter 13, Problem 13.133P

Chapter 13, Problem 13.138P

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Solution Summary: The author explains the temperature of the heater required for specified drying rate.

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