Heat and Mass Transfer: Fundamentals and Applications
6th Edition
ISBN: 9781260440058
Author: CENGEL, Yunus
Publisher: MCGRAW-HILL HIGHER EDUCATION
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Textbook Question
Chapter 3, Problem 219P
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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