Water is to be heated from 35 °C to 65 °C in a rough tube with a relative roughness of 0.001. The tube has an electric heater provides a constant heat flux such that the tube average wall temperature is 20 °C above the average water bulk temperature. The Reynolds number used for calculating the heat-transfer coefficient is 100,000. Calculate the length of tube required for heating, expressed in meters, if the tube has a diameter of 1 cm.

Water is to be heated from 35 °C to 65 °C in a rough tube with a relative roughness of 0.001. The tube has an electric heater provides a constant heat flux such that the tube average wall temperature is 20 °C above the average water bulk temperature. The Reynolds number used for calculating the heat-transfer coefficient is 100,000. Calculate the length of tube required for heating, expressed in meters, if the tube has a diameter of 1 cm.

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.

Chapter6: Forced Convection Over Exterior Surfaces

Section: Chapter Questions

Problem 6.19P

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