Mild steel nails were driven through a solid wood wall consisting of two layers, each 15 mm thick, for reinforcement. If the total cross- sectional area of the nails is 0.75% of the wall area, determine the unit thermal conductance of the composite wall, total heat flow, heat flow through the nail alone and the percent of the total heat flow that passes through the nails when the temperature difference across the wall is 35°C. Neglect contact resistance between the wood layers. Wood (Pine) (kyw) = 0.15 W/(m K); Mild steel (1% C) (kg) = 43 W/(m K)

Mild steel nails were driven through a solid wood wall consisting of two layers, each 15 mm thick, for reinforcement. If the total cross- sectional area of the nails is 0.75% of the wall area, determine the unit thermal conductance of the composite wall, total heat flow, heat flow through the nail alone and the percent of the total heat flow that passes through the nails when the temperature difference across the wall is 35°C. Neglect contact resistance between the wood layers. Wood (Pine) (kyw) = 0.15 W/(m K); Mild steel (1% C) (kg) = 43 W/(m K)

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 1.37P: 1.37 Mild steel nails were driven through a solid wood wall consisting of two layers, each 2.5-cm...

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