Elements Of Electromagnetics
7th Edition
ISBN: 9780190698614
Author: Sadiku, Matthew N. O.
Publisher: Oxford University Press
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Steel pipe (outer diameter 100 mm) is covered with two layers of insulation. The inner layer, 40 mm thick, has a thermal conductivity of 0.07 W / (m K). The outer layer, 20 mm thick, has a thermal conductivity of 0.15 W / (m K). Pipes are used to delivering steam with a pressure of 600 kPa. The temperature on the outer insulation surface is 24 ° C. If the pipe is 10 m long, determine the following: (assuming that the conduction heat transfer resistance of the steel pipe and the vapor convection resistance are negligible).
a. Hourly heat loss ... (kj / hr)
b. temperature between insulation layers ... (° C.)
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