A house has a composite wall of wood, fiberglass insulation, and plaster board, as indicated in the sketch. On a cold winter day, the convection heat transfer coefficients are ho = 60 W/m².K and h; = 20 W/m2.K. The total wall surface area is 500 m². The plaster board thickness is Lp = 10 mm, the glass fiber thickness is L = 100 mm, and the plywood siding thickness is Ls = 20 mm. The temperature inside is T; = 20°C and the temperature outside is T, = -15°C. Determine the total heat loss through the wall. Plaster board, k Inside h;, Too, i 111 Glass fiber blanket (28 kg/m³), kb Lp -Plywood siding, k Outside hos Too, o 111

A house has a composite wall of wood, fiberglass insulation, and plaster board, as indicated in the sketch. On a cold winter day, the convection heat transfer coefficients are ho = 60 W/m².K and h; = 20 W/m2.K. The total wall surface area is 500 m². The plaster board thickness is Lp = 10 mm, the glass fiber thickness is L = 100 mm, and the plywood siding thickness is Ls = 20 mm. The temperature inside is T; = 20°C and the temperature outside is T, = -15°C. Determine the total heat loss through the wall. Plaster board, k Inside h;, Too, i 111 Glass fiber blanket (28 kg/m³), kb Lp -Plywood siding, k Outside hos Too, o 111

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 1.40P: As a designer working for a major electric appliance manufacturer, you are required to estimate the...

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