n a thermal power plant a hot furnace consisting of three layers of wall in which first layer is made up of insulation brick of 15 cm thickness and conductivity 0.45 W/mK. The inner surface of the...

n a thermal power plant a hot furnace consisting of three layers of wall in which first layer is made up of insulation brick of 15 cm thickness and conductivity 0.45 W/mK. The inner surface of the furnace wall is exposed to hot gases at 900°C with a convection coefficient of 85 W/m²K. This layer is backed by a 15 cm layer of firebrick of conductivity 0.85 W/mK. The third layer is the plate backing of 10 mm thickness of conductivity 35 W/mK.. The plate is exposed to air at 30°C with a convection coefficient of 15 W/m²K. Determine the heat flow, the intermediate surface temperatures and the overall heat transfer coefficient. Also draw the equivalent circuit diagram.