A composite insulating wall has a layer of red brick and another insulating brick held together by an aluminum rivet of 30mm diameter per 0.1m? of the surface. The red brick layer is 100 mm thick, with the hot surface at 225°C, and the insulating brick layer is 250 mm thick with the cold surface at 37°C. The thermal conductivities of the materials are: for the aluminum rivet = 203.6W/mK, for the red brick = 0.93W/mK and for the insulating brick %3D 0.116W/mK. Estimate the percentage increase in heat transfer rate due to rivets.

A composite insulating wall has a layer of red brick and another insulating brick held together by an aluminum rivet of 30mm diameter per 0.1m? of the surface. The red brick layer is 100 mm thick, with the hot surface at 225°C, and the insulating brick layer is 250 mm thick with the cold surface at 37°C. The thermal conductivities of the materials are: for the aluminum rivet = 203.6W/mK, for the red brick = 0.93W/mK and for the insulating brick %3D 0.116W/mK. Estimate the percentage increase in heat transfer rate due to rivets.

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 1.10P: 1.10 A heat flux meter at the outer (cold) wall of a concrete building indicates that the heat loss...

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