Fundamentals of Heat and Mass Transfer
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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Chapter 1, Problem 1.71P
(a)
To determine
The case temperature when
(b)
To determine
To Plot: The maximum allowable heat dissipation for variation in
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A pipe transports refrigerant which goes at a temperature of -60 ° C,
it has 2 ”internal diameter and 2.3” external diameter with a thermal conductivity of K1= 389W / mK. Insulation of 30cm thick is placed on it with a thermal conductivity of k20.04W / mK the internal convection coefficient is 150 W / m2K. the air is moving at 10m / s on the external surface of the tube which is at a temperature of 20 ° C and the environment is at 40 ° C. Find the external convection coefficient and the total transfer rate of the system.
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k=215 W/moC
a= 8,4x10-5m2/s
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Chapter 1 Solutions
Fundamentals of Heat and Mass Transfer
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