A steel tube (K = 43.26 W/mK) of 5.08 cm inner diameter and 7.62 cm outer diameter is covered with 2.5 cm layer of insulation (K = 0.208 W/mK) the inside surface of the tube receivers heat from a hot gas at the temperature of 316oC with heat transfer co-efficient of 28 W/m2K.
While the outer surface exposed to the ambient air at 30oC with heat transfer co-efficient of 17 W/m2K. Calculate heat loss for 3 m length of the tube.