3.13 Consider a composite wall of overall height H = 20 mm and thickness L = 30 mm. Section A has thickness LA = 10 mm, and sections B and C each have height HB = 10 mm and thickness LB = 20 mm. The temperatures of the left and right faces of the composite wall are T1 = 50°C and T2 = 20°C, respectively. If the top and bottom of the wall are insulated, determine the heat rate per unit wall depth for each of the following three cases. Which case yields the largest heat rate per unit depth? Which yields the smallest heat rate per unit depth? Case kĄ(W/m • K) kB(W/m · K) kc(W/m · K) 1 2 3 3 1 3 3 1. A B H. T2

3.13 Consider a composite wall of overall height H = 20 mm and thickness L = 30 mm. Section A has thickness LA = 10 mm, and sections B and C each have height HB = 10 mm and thickness LB = 20 mm. The temperatures of the left and right faces of the composite wall are T1 = 50°C and T2 = 20°C, respectively. If the top and bottom of the wall are insulated, determine the heat rate per unit wall depth for each of the following three cases. Which case yields the largest heat rate per unit depth? Which yields the smallest heat rate per unit depth? Case kĄ(W/m • K) kB(W/m · K) kc(W/m · K) 1 2 3 3 1 3 3 1. A B H. T2

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.

Chapter2: Steady Heat Conduction

Section: Chapter Questions

Problem 2.24P

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