Discuss the following:
Q: A stainless steel (AISI 304) tube used to transport a chilled pharmaceutical has an inner diameter of 36 mm and a wall thickness of 2 mm. The pharmaceutical and ambient air are at temperatures of 6°C and 23°C, respectively, while the corresponding inner and outer convection coefficients are 400 W/m2 · K and 6 W/m2 · K respectively.
(a) What is the heat gain per unit tube length?
(b) What is the heat gain per unit length if a 10-mm-thick layer of calcium silicate insulation (kins = 0.050 W/m · K) is applied to the tube?