Consider a plane composite wall that is composed of two materials of thermal conductivities k_A = 0.1 W/m ∙ K and k_B = 0.04 W/m ∙ K and thicknesses L_A = 10 mm and L_B = 20 mm. The contact resistance at the interface between the two materials is known to be 0.30 m² ∙ K/W. Material A adjoins a fluid at 200°C for which h = 10 W/m² ∙ K, and material B adjoins a fluid at 40°C for which h = 20 W/m² ∙ K.

(a) What is the rate of heat transfer through a wall that is 2 m high by 2.5 m wide?

(b) Sketch the temperature distribution.