5. The wall of an oven consists of a 0.25-inch-thick layer of steel with a thermal conductivity of 8.7 Btu/(h-ft-°R) and a layer of brick with a thermal conductivity of 0.42 Btu/(h-ft-°R). At steady state, a temperature decrease of 1.2°F occurs over the steel layer. The inner temperature of the steel layer is 540°F. If the temperature of the outer surface of the brick must be no greater than 105°F, determine the minimum thickness of the brick, in inches, that ensures that this limit is met. T₁ = 540°F Steel AT -1.2°F- Brick -To ≤ 105°F

5. The wall of an oven consists of a 0.25-inch-thick layer of steel with a thermal conductivity of 8.7 Btu/(h-ft-°R) and a layer of brick with a thermal conductivity of 0.42 Btu/(h-ft-°R). At steady state, a temperature decrease of 1.2°F occurs over the steel layer. The inner temperature of the steel layer is 540°F. If the temperature of the outer surface of the brick must be no greater than 105°F, determine the minimum thickness of the brick, in inches, that ensures that this limit is met. T₁ = 540°F Steel AT -1.2°F- Brick -To ≤ 105°F

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 2.4P: A plane wall 15 cm thick has a thermal conductivity given by the relation k=2.0+0.0005T[W/mK] where...

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