Practice question

Question

An evaporator is insulated using glass wool material of 0.15 m thickness. The inner most surface and the outer surface of the insulation are at 700 ⁰ C and 80 ⁰ C respectively. The mean thermal conductivity of the glass wool under these conditions is 0.29 W.m ⁻¹ .K ⁻ ¹ . The rate of heat loss (in W ) through 1.2 m ² of the evaporator wall surface (rounded off to the nearest integer) is __________.