A composite plane wall consists of a 3-in.-thick layer of insulation (ks = 0.029 Btu/h · ft · °R) and a 0.75-in.-thick layer of siding (ks = 0.058 Btu/h · ft · °R). The inner temperature of the insulation is 67°F. The outer temperature of the siding is 0°F. Determine at steady state (a) the temperature at the interface of the two layers, in °F, and (b) the rate of heat transfer through the wall in Btu/h-ft2 of surface area.

A composite plane wall consists of a 3-in.-thick layer of insulation (ks = 0.029 Btu/h · ft · °R) and a 0.75-in.-thick layer of siding (ks = 0.058 Btu/h · ft · °R). The inner temperature of the insulation is 67°F. The outer temperature of the siding is 0°F. Determine at steady state (a) the temperature at the interface of the two layers, in °F, and (b) the rate of heat transfer through the wall in Btu/h-ft2 of surface area.

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter1: Basic Modes Of Heat Transfer

Section: Chapter Questions

Problem 1.19P: 1.19 A cryogenic fluid is stored in a 0.3-m-diameter spherical container is still air. If the...

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