Air flows hydrodynamically and thermally fully developed at an average speed of 0.5 m/s through a thin-walled pipe with a diameter of 2.5 cm. Air can be heated in two different ways. In the first, the air can be heated at a constant surface temperature by means of a steam from the outside of the pipe, and in the second with an electric heater (thus providing a constant heat flux). Calculate the heat convection coefficients for both heating methods. According to this; Given: Properties of air at 350°K: υ= 20.76.10-6 m2/s, k =0.03 W/mK, Pr=0.70

Air flows hydrodynamically and thermally fully developed at an average speed of 0.5 m/s through a thin-walled pipe with a diameter of 2.5 cm. Air can be heated in two different ways. In the first, the air can be heated at a constant surface temperature by means of a steam from the outside of the pipe, and in the second with an electric heater (thus providing a constant heat flux). Calculate the heat convection coefficients for both heating methods. According to this; Given: Properties of air at 350°K: υ= 20.76.10-6 m2/s, k =0.03 W/mK, Pr=0.70

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 7.4P

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