A stainless steel tube (k = 14,2 W / m.K) 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) e 6 W / (m2.K), respectively. a) Sketch and explain in detail the heat download process in the above situation. (b) What is the heat gain per unit tube length? (c) What is the heat gain per unit length if a 20-mm-thick layer of calcium silicate insulation (kins=0.050W/m⋅K) is placed on the outer surface of the tube?

A stainless steel tube (k = 14,2 W / m.K) 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) e 6 W / (m2.K), respectively. a) Sketch and explain in detail the heat download process in the above situation. (b) What is the heat gain per unit tube length? (c) What is the heat gain per unit length if a 20-mm-thick layer of calcium silicate insulation (kins=0.050W/m⋅K) is placed on the outer surface of the tube?

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter6: Forced Convection Over Exterior Surfaces

Section: Chapter Questions

Problem 6.36P

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