Hot water at an average temperature of 80°C and an average velocity of 1.5 m/s is flowing through a 25-m section of a pipe that has an outer diameter of 5 cm. The pipe extends 2 m in the ambient air above the ground, dips into the ground (k= 1.5 W/m-°C) vertically for 3 m, and continues horizontally at this depth for 20 m more before it enters the next building. The first section of the pipe is exposed to the ambient air at 8°C with a heat transfer coefficient of 22 W/m2.°C. If the surface of the ground is covered with snow at 0°C, determine: (a) Heat loss from the part of the tube that is on the ground. (b) Heat loss for vertical part of the tube. The shape factor, and the rate of heat loss on the horizontal part that is in the ground.

Hot water at an average temperature of 80°C and an average velocity of 1.5 m/s is flowing through a 25-m section of a pipe that has an outer diameter of 5 cm. The pipe extends 2 m in the ambient air above the ground, dips into the ground (k= 1.5 W/m-°C) vertically for 3 m, and continues horizontally at this depth for 20 m more before it enters the next building. The first section of the pipe is exposed to the ambient air at 8°C with a heat transfer coefficient of 22 W/m2.°C. If the surface of the ground is covered with snow at 0°C, determine: (a) Heat loss from the part of the tube that is on the ground. (b) Heat loss for vertical part of the tube. The shape factor, and the rate of heat loss on the horizontal part that is in the ground.

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 7.27P

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