1. The wall of a cold room consists of a layer of cork sandwiched between the outer and inner walls of wood, the wood walls being each 30 mm thick. The inside atmosphere of the room is maintained at -20°C when the external atmospheric temperature is 25°C, and the heat loss through the wall is 42 W/m². Taking the thermal conductivity of wood and cork as 0.20 W/m-K and 0.05 W/m-K respectively, and the rate of heat transfer between each exposed wood surface and their respective atmospheres as 15 W/m²-K. Calculate the thickness of the cork in mm.

1. The wall of a cold room consists of a layer of cork sandwiched between the outer and inner walls of wood, the wood walls being each 30 mm thick. The inside atmosphere of the room is maintained at -20°C when the external atmospheric temperature is 25°C, and the heat loss through the wall is 42 W/m². Taking the thermal conductivity of wood and cork as 0.20 W/m-K and 0.05 W/m-K respectively, and the rate of heat transfer between each exposed wood surface and their respective atmospheres as 15 W/m²-K. Calculate the thickness of the cork in mm.

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 1.1P: 1.1 On a cold winter day, the outer surface of a 0.2-m-thick concrete wall of a warehouse is exposed...

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