Heat and Mass Transfer: Fundamentals and Applications
5th Edition
ISBN: 9780073398181
Author: Yunus A. Cengel Dr., Afshin J. Ghajar
Publisher: McGraw-Hill Education
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Textbook Question
Chapter 3, Problem 207P
A room at 20°C air temperature is losing heat to the outdoor air at 0°C at a rate of 1000 W through a 2.5-m-high and 4-m-long wall. Now the wall is insulated with 2-cm-thick insulation with a conductivity of 0.02 W/m⋅K. Detenuine the rate of heat loss from the room through this vall after insulation. Assume the heat transfer coefficients on the inner and outer surfaces of the wall, the room air temperature, and the outdoor air temperature remain unchanged. Also, disregard radiation.
(a) 20 W
(b) 561 W
(c) 388 W
(d) 167W
(e) 200 W
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Chapter 3 Solutions
Heat and Mass Transfer: Fundamentals and Applications
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