Hot oil flows at a temperature of 165 oC through a steel pipe with an outer diameter of 38.0mm and a wall thickness of 3.0mm. Since the heat conduction coefficient of the pipe material is 40W / m oC, the inner and outer surface heat transfer coefficients of the pipe are 4000 and 15W / m2 oC, respectively, and the outdoor temperature is 22 oC a) The insulation material on the pipe is removed, that is, when the bare pipe is a total of 50 (m) Find the total heat flux from the long pipe to the outside. b) If the pipe surface is covered with an insulation material with a thickness of 5 cm and a heat transfer coefficient of 0.065W / moC, how many% decrease in heat loss?

Hot oil flows at a temperature of 165 oC through a steel pipe with an outer diameter of 38.0mm and a wall thickness of 3.0mm. Since the heat conduction coefficient of the pipe material is 40W / m oC, the inner and outer surface heat transfer coefficients of the pipe are 4000 and 15W / m2 oC, respectively, and the outdoor temperature is 22 oC a) The insulation material on the pipe is removed, that is, when the bare pipe is a total of 50 (m) Find the total heat flux from the long pipe to the outside. b) If the pipe surface is covered with an insulation material with a thickness of 5 cm and a heat transfer coefficient of 0.065W / moC, how many% decrease in heat loss?

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.

Chapter2: Steady Heat Conduction

Section: Chapter Questions

Problem 2.18P: Estimate the rate of heat loss per unit length from a 5-cm ID, 6-cm OD steel pipe covered with...

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