Question

It is a question about the thermal heat transfer problem.

A wall consists of 2 layers in parallel: A=3m^2 and B=7m^2. The indoor air temperature and outdoor air temperature are 20C and 10C, respectively. The rate of heat flow through the whole wall is not to exceed 50W by adding a thermal insulation on the wall ( on both A and B), What is the required thickness of the thermal insulation layer? The thermal conductivity of the thermal insulation layer is 0.05W/(m.K)

Answer #1

Here, H = rate of heat flow

A = area of crossection

Th - Tl = temperature difference

k = thermal conductivity

Here, H = k * A * [(Th - Tl)/x]

=> 50 = 0.05 * 10 * [(20 - 10)/x]

=> x = 0.1 m

Thus, the required thickness of the thermal insulation layer = 0.1 m

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