A steam pipe of 0.12-m outside diameter is insulated with a layer of calcium silicate. (a) If the insulation is 20 mm thick and its inner and outer surfaces are maintained at Ts,1 = 800 K and Ts,2 = 490 K, respectively, what is the rate of heat loss per unit length ′ of the pipe? (b) We wish to explore the effect of insulation thickness on the rate of heat loss q ′ and outer surface temperature Ts,2 , with the inner surface temperature fixed at Ts,1 = 800 K. The outer surface is exposed to an airflow (T[infinity] = 25°C) that maintains a convection coefficient of h = 25 W/m2 ·K and to large surroundings for which Tsur = T[infinity] = 25°C. The surface emissivity of calcium silicate is approximately 0.8. Compute and plot the temperature distribution in the insulation as a function of the dimensionless radial coordinate, (r − r1)/(r2 − r1), where r1 = 0.06 m and r2 is a variable (0.06 < r2 ≤ 0.20 m). Compute and plot the rate of heat loss as a function of the insulation thickness for 0 ≤ (r2 − r1) ≤ 0.14 m.