A composite wall made of two materials consists of a 10 cm thick layer of brick (kb=0.15 W/m/K) and a layer of insulation (k₁= 0.04 W/m/K). Knowing that the surface temperature of the brick is 35 °C and that the contact temperature between the brick and insulation material is 30 °C, determine a) the insulation thickness if the surface temperature of the insulation must be lower than 20 °C, b) the heat transfer value kW/m²

A composite wall made of two materials consists of a 10 cm thick layer of brick (kb=0.15 W/m/K) and a layer of insulation (k₁= 0.04 W/m/K). Knowing that the surface temperature of the brick is 35 °C and that the contact temperature between the brick and insulation material is 30 °C, determine a) the insulation thickness if the surface temperature of the insulation must be lower than 20 °C, b) the heat transfer value kW/m²

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 2.54P

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