A 12 m long and 5 m high wall is constructed of two layers of 1 cm thick sheetrock (& = 0.17 W/m. °C) spaced 16 cm by wood studs & = 0.11 W/m °C) whose cross section is 16 cm x 5 cm. The studs are placed vertically 60 cm apart, and the space between them is filled with fiberglass insulation (* = 0.034 W/m. °C). The house is maintained at 20°C and the ambient temperature outside is -9°C. Taking the heat transfer coefficients at the inner and outer surfaces of the house to be 8.3 and 34 W/m?. °C respectively, determine (a) The thermal resistance of the wall considering a representative section of it (b) The rate of heat transfer through the wall

A 12 m long and 5 m high wall is constructed of two layers of 1 cm thick sheetrock (& = 0.17 W/m. °C) spaced 16 cm by wood studs & = 0.11 W/m °C) whose cross section is 16 cm x 5 cm. The studs are placed vertically 60 cm apart, and the space between them is filled with fiberglass insulation (* = 0.034 W/m. °C). The house is maintained at 20°C and the ambient temperature outside is -9°C. Taking the heat transfer coefficients at the inner and outer surfaces of the house to be 8.3 and 34 W/m?. °C respectively, determine (a) The thermal resistance of the wall considering a representative section of it (b) The rate of heat transfer through the wall

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.

Chapter2: Steady Heat Conduction

Section: Chapter Questions

Problem 2.1DP

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