Introduction to Heat Transfer
6th Edition
ISBN: 9780470501962
Author: Frank P. Incropera, David P. DeWitt, Theodore L. Bergman, Adrienne S. Lavine
Publisher: Wiley, John & Sons, Incorporated
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Chapter 3, Problem 3.59P
a.
To determine
heat loss per unit length from the bare pipe (no insulation)
b.
To determine
Number of years needed to pay back the initial investment in insulation
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A furnace must be built with an inner layer of refractory brick (conductivity 1.27 Kcal/h mºC). This layer must be coated with a layer of insulating brick (conductivity 0.134 Kcal/hm ºC) 22 cm thick, in turn covered with a 15 cm layer of building brick (conductivity 0.75 Kcal/ hm°C). The inner surface of the refractory wall will operate at 1150ºC and the outside at 65ºC. How many centimeters of refractory brick would be required for the insulation not to exceed 930ºC (safety limit of the material in question).
A radiator plate of 0.2-m (wide) x 0.4-m (height) is in a room of 22°C.
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Chapter 3 Solutions
Introduction to Heat Transfer
Ch. 3 - Consider the plane wall of Figure 3.1, separating...Ch. 3 - A new building to be located in a cold climate is...Ch. 3 - The rear window of an automobile is defogged by...Ch. 3 - The rear window of an automobile is defogged by...Ch. 3 - A dormitory at a large university, built 50 years...Ch. 3 - In a manufacturing process, a transparent film is...Ch. 3 - Prob. 3.7PCh. 3 - A t=10-mm-thick horizontal layer of water has a...Ch. 3 - Prob. 3.9PCh. 3 - The wind chill, which is experienced on a cold,...
Ch. 3 - Prob. 3.11PCh. 3 - A thermopane window consists of two pieces of...Ch. 3 - A house has a composite wall of wood, fiberglass...Ch. 3 - Prob. 3.14PCh. 3 - Prob. 3.15PCh. 3 - Work Problem 3.15 assuming surfaces parallel to...Ch. 3 - Consider the oven of Problem 1.54. 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