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served Problem 07.135- Surface Temperature of Stainless Steel Steam Pipe Steam at 250°C flows in a stainless steel pipe (k= 15 W/m-K) whose inner and outer diameters are 4 cm and 4.6 cm, respectively. The pipe is covered with 3.5-cm thick glass wool insulation (k= 0.038 W/m-K) whose outer surface has an emissivity of 0.3. Heat is lost to the surrounding air and surfaces at 3°C by convection and radiation. Taking the heat transfer coefficient inside the pipe to be 80 W/m2.K, determine the surface temperature, when the length of the pipe is 1.2 m and when air is flowing across the pipe at 5 m/s. Evaluate the air properties at a film temperature of 10°C and 1 atm. Assuming a film temperature of 10°C and the properties of air based on this temperature are k= 0.02439 W/m 'C, v=1.426 x 10-5 m2/s, Pr=0.7336. The surface temperature is Help