In a mutlilayered rectangular walll, the thermal resistance of the fi rst layer is 0.005°C/W, the resistance of the second layer is 0.2°C/W, and for the third layer it is 0.1°C/W. The overall temperature gradient in the multilayered wall from one side to another is 70°C.
a. Determine the heat fl ux through the wall.
b. If the thermal resistance of the second layer is doubled to 0.4°C/W, what will be its infl uence in % on the heat fl ux, assuming the temperature gradient remains the same?