One insulated wall of a cold-storage compartment is 8 m long by 2.5 m high and consists of an outer steel plate 18 mm thick. An inner wood wall is 22.5 m thick. The steel and wood are 90 mm apart to form a cavity which is filled with cork. If the temperature drop across the extreme faces of the composite wall is 15°C. Calculate the HEAT TRANSFER PER HOUR through the wall and the TEMPERATURE DROP across the thickness of the cork. Take the coefficients of thermal conductivity for steel, cork and wood as 45 W/m-K, 0.045 W/m-K, and 0.18 W/m-K respectively.

One insulated wall of a cold-storage compartment is 8 m long by 2.5 m high and consists of an outer steel plate 18 mm thick. An inner wood wall is 22.5 m thick. The steel and wood are 90 mm apart to form a cavity which is filled with cork. If the temperature drop across the extreme faces of the composite wall is 15°C. Calculate the HEAT TRANSFER PER HOUR through the wall and the TEMPERATURE DROP across the thickness of the cork. Take the coefficients of thermal conductivity for steel, cork and wood as 45 W/m-K, 0.045 W/m-K, and 0.18 W/m-K respectively.

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 1.35P: A section of a composite wall with the dimensions shown below has uniform temperatures of 200C and...

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