Heat transfer Air flows through a smooth thin-walled rectangular duct of height, a= 0.3 m and width, b=1 m. The air is heated by the duct walls at a uniform heat flux of 250 W/m2 . At some location inside the duct, the mean velocity and temperature of air was measured to be um = 0.05 m/s and Tm = 350 K, respectively. (a) What is the hydraulic diameter of the duct? (b) What is the Reynolds number for the flow in the duct? (c) Is the flow laminar or turbulent? (d) Assuming fully developed flow, what is the heat transfer coefficient (h) at this location?

Heat transfer Air flows through a smooth thin-walled rectangular duct of height, a= 0.3 m and width, b=1 m. The air is heated by the duct walls at a uniform heat flux of 250 W/m2 . At some location inside the duct, the mean velocity and temperature of air was measured to be um = 0.05 m/s and Tm = 350 K, respectively. (a) What is the hydraulic diameter of the duct? (b) What is the Reynolds number for the flow in the duct? (c) Is the flow laminar or turbulent? (d) Assuming fully developed flow, what is the heat transfer coefficient (h) at this location?

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 7.8P

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