Consider a plane composite wall that is composed of two materials of thermal conductivities ka 0.1 w/mk and kb 0.04 w/mk and thicknesses la 10 mm and lb 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 2.5 meters high by 2 meters side?
b)what is the temperature at the exposed surface of material a?
c)what is the temperature at the exposed surface of material b?
d)sketch the temperature distribution.