A 50 m metal pipe, with a thermal conductivity of 60 W/(m. K), is carrying pasteurised orange juice with a temperature of 75 °C. The pipe has an inside diameter of 50 mm and a wall thickness of 15 mm. To keep the orange juice at as high a temperature as possible, a 50 mm thick layer of fibreglass insulation is added to the pipe. This fibreglass has a thermal conductivity of 0.05 W/(m. K). If the the temperature outside the pipe is 20 °C, how much heat will be lost from the pipe? Assume that the conditions are steady-state. What is the resistance to heat flow in the metal pipe?: What is the resistance to heat flow in the fibreglass insulation?: What is the overall rate of heat flow from this insulated pipe? K/W W K/W

A 50 m metal pipe, with a thermal conductivity of 60 W/(m. K), is carrying pasteurised orange juice with a temperature of 75 °C. The pipe has an inside diameter of 50 mm and a wall thickness of 15 mm. To keep the orange juice at as high a temperature as possible, a 50 mm thick layer of fibreglass insulation is added to the pipe. This fibreglass has a thermal conductivity of 0.05 W/(m. K). If the the temperature outside the pipe is 20 °C, how much heat will be lost from the pipe? Assume that the conditions are steady-state. What is the resistance to heat flow in the metal pipe?: What is the resistance to heat flow in the fibreglass insulation?: What is the overall rate of heat flow from this insulated pipe? K/W W K/W

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 7.50P

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