Air at 20 ◦ C flows inside a pipe 18-mm-ID having a uniform heat flux of 150 W/m 2 on the surface, the average flow velocity at entry being 1.0 m/s. The air pressure is 2 bar. Determine the value of convection coefficient. If the pipe is 2.5 m long, determine the air exit temperature and the wall temperature at the exit. Assume fully developed hydrodynamic boundary layer.

Air at 20 ◦ C flows inside a pipe 18-mm-ID having a uniform heat flux of 150 W/m 2 on the surface, the average flow velocity at entry being 1.0 m/s. The air pressure is 2 bar. Determine the value of convection coefficient. If the pipe is 2.5 m long, determine the air exit temperature and the wall temperature at the exit. Assume fully developed hydrodynamic boundary layer.

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 7.34P

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