A cold storage room is constructed of an inner layer of 12.7 mm of pine, a middle layer of 101.6 mm of cork board, and an outer layer of 76.2 mm of concrete. The wall surface temperature is 255.4 K inside the cold room and 297.1 K at the outside surface of the concrete. The conductivities for pine, for cork board and for concrete are 0.151 W/m.K, 0.0433 W/m.K, 0.762 W/m.K respectively. Calculate the heat loss in W for 1 m2 and the temperature at the interface between the wood and cork board.

A cold storage room is constructed of an inner layer of 12.7 mm of pine, a middle layer of 101.6 mm of cork board, and an outer layer of 76.2 mm of concrete. The wall surface temperature is 255.4 K inside the cold room and 297.1 K at the outside surface of the concrete. The conductivities for pine, for cork board and for concrete are 0.151 W/m.K, 0.0433 W/m.K, 0.762 W/m.K respectively. Calculate the heat loss in W for 1 m2 and the temperature at the interface between the wood and cork board.

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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A cold storage room is constructed of an inner layer of 12.7mm of pine, a middle inner of 101.6mm of cork board, and an outer layer of 76.2mm of concrete. The wall surface temperature is 255.4 K inside the cold room and 297.1 k at the outside surface of the concrete. Thermal conductivity of pine is 0.151; corkboard 0.0433; concrete 0.762W/m-K. Calculate the heat loss in W for 1m^2 surface area.
A food cold storage room is to be constructed of an inner layer of 19.1 mm of pine wood, a middle layer of cork board, and an outer layer of 50.8 mm of concrete. The inside wall surface temperature is -17.8°C and the outside surface temperature is 29.4 °C at the outer concrete surface. The mean conductivities are for pine, 0.151; cork, 0.0433; and concrete, 0.762 W/m·K. The total inside surface area of the room to use in the calculation is approximately 39 m2 (neglecting corner and end effects). What thickness of cork board is needed to keep the heat loss to 586 W?
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