-:) Given a tank wall with a thickness of 0.01 m and a thermal conductivity of 0.2 W/m-K. The convective coefficient is 100 and 10 W/m² K for inner and outer surfaces, respectively. An insulation layer with a thermal conductivity of 0.06 W/m-K is used to reduce the heat flux by 90%, If all the parameters are assumed to remain the same, what is the thickness of the insulation layer? (in meter) (c) 0.128 (a) 0.052 (d) 0.086 (b) 0.012 (e) 0.043

Q5B) A steel pipe of 170 mm inner diameter and 190 mm outer diameter with thermal conductivity 55 W/m. K is covered with two layers of insulation. The thickness of first layer is 25 mm (k = 0.1 W/m. K) and second layer thickness is 40 mm (k = 0.18 W/m.K). The temperature of steam and inner surface of steam pipe is 320 °C and outer surface of insulation is 80 °C. Ambient air temperature is 25 °C. The surface coefficient for inside and outside surfaces are 230 W/m². K and 6 W/m². K respectively. Determine the heat loss per meter length of steam pipe and layer of contact temperatures and also calculate overall heat transfer coefficient.

Steel pipe (outer diameter 100 mm) is covered with two layers of insulation. The inner layer, 40 mm thick, has a thermal conductivity of 0.07 W / (m K). The outer layer, 20 mm thick, has a thermal conductivity of 0.15 W / (m K). Pipes are used to deliver steam with a pressure of 600 kPa. The temperature on the outer insulation surface is 24 ° C. If the pipe is 8 m long, determine the following: (assuming that the conduction heat transfer resistance of the steel pipe and the vapor convection resistance are negligible). a. Heat loss per hour. = kJ / hour. b. Temperature between insulation layers. = ° C

As shown in the sketh below, a steam pipe of 0.12-m inside diameter is insulated with a layer of calcium silicate. "2. Ta2} 1. Ta,1} Steam Insulation (a) If the insulation is 10 mm thick and its inner and outer surfaces are maintained at T, = 800 K and Ta = 490 K. respectively,. what is the rate of heat loss per unit length (q) of the pipe, in W/m? (b) Determine the rate of heat loss per unit length (d), in W/m, and outer surface temperature T,2, in K, for the steam pipe with the Inner surface temperature fixed at T = 800 K, inner radius = 0.06 m, and outer radius n = 0.18 m. The outer surface is exposed to an airflow (T 25°C) that maintains a convection coefficient of h = 25 W/m2-K and to large surroundings for which Tur = T, = 25°C. The surface emissivity of calcium silicate is approximately 0.8.