Question #2 (a) Calculate the total thermal resistance per unit length of tube for a 10 mm diameter thin tube having the following insulation thicknesses: 0, 2, 5, 10, 20 and 40mm. The insulation is composed of Cellular Glass (k=0.055 W/m K). The outer surface convection coefficient is 5 W/m²K. Neglect the resistance of the metal tube. (b) Determine the critical radius re of the system and the corresponding insulation thickness.

Question #2 (a) Calculate the total thermal resistance per unit length of tube for a 10 mm diameter thin tube having the following insulation thicknesses: 0, 2, 5, 10, 20 and 40mm. The insulation is composed of Cellular Glass (k=0.055 W/m K). The outer surface convection coefficient is 5 W/m²K. Neglect the resistance of the metal tube. (b) Determine the critical radius re of the system and the corresponding insulation thickness.

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.

Chapter7: Forced Convection Inside Tubes And Ducts

Section: Chapter Questions

Problem 7.48P

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