A cooler wall is made up of 2 outer shell layers of plastic

A cooler wall is made up of 2 outer \"shell\" layers of plastic, each having a conductivity of 4k, and an inner layer of insulation having a conductivity of k (Fig. 1). The thickness of each shell is d, while the thickness of the insulation is 2d. Assuming one-dimensional, steady-state conduction and a temperature difference between the inner (cooler) surface and outer surface of Delta T, calculate the heat flux into the cooler.

Solution

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