Engineering, 26.02.2020 01:20 keeks11

Consider a composite wall consisting of 1 cm of plywood (on the inside) and 11 cm brick (on the outside) separated by 10 cm of glass fiber blanket (of density 40 kg/m?). The interior of the wall is exposed to 21°C air with a convection coefficient of 20 W/m²K and the exterior of the wall is exposed to -10°C air with a convection coefficient of 50 W/m²K. The surface area of the wall is 300 m². a. Find the total thermal resistance, overall heat transfer coefficient, and heat transfer rate from the inside air to the outside air. b. If the convection coefficient of the outside air on a windy day was 250 W/m² instead, by what percentage would the heat transfer rate be different? c. Would you expect that radiation would significantly affect your calculations? Why or why not?

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Consider a composite wall consisting of 1 cm of plywood (on the inside) and 11 cm brick (on the outs...

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