3. Steam at 320°C flows in a stainless-steel pipe (k = 15 W/m °C) whose inner and outer diameters are 5 cm and 5.5 cm, respectively. The pipe is covered with 3-cm-thick glass wool insulation (k = 0.038 W/m-°C). Heat is lost to the surroundings at 5 °C by natural convection and radiation, with a combined natural convection and radiation heat transfer coefficient of 15 W/m².°C. Taking the heat transfer coefficient inside the pipe to be 80 W/m².°C, determine the rate of heat loss from the steam per unit length of the pipe. Also determine the temperature drops across the pipe shell and the insulation.

3. Steam at 320°C flows in a stainless-steel pipe (k = 15 W/m °C) whose inner and outer diameters are 5 cm and 5.5 cm, respectively. The pipe is covered with 3-cm-thick glass wool insulation (k = 0.038 W/m-°C). Heat is lost to the surroundings at 5 °C by natural convection and radiation, with a combined natural convection and radiation heat transfer coefficient of 15 W/m².°C. Taking the heat transfer coefficient inside the pipe to be 80 W/m².°C, determine the rate of heat loss from the steam per unit length of the pipe. Also determine the temperature drops across the pipe shell and the insulation.

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 7.29P

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