Convection, conduction, and overall u. a gas at 450 k is flowing inside a 2-in. steel pipe, schedule 40. the pipe is insulated with 51 mm of lagging having a mean k = 0.0623 w/m · k. the convective heat-transfer coefficient of the gas inside the pipe is 30.7 w/m2 · k and the convective coefficient on the outside of the lagging is 10.8. the air is at a temperature of 300 k. calculate the heat loss per unit length of 1 m of pipe using resistances. repeat, using the overall u0 based on the outside area a0.