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A flow of air develops in a horizontal cylindrical duct, of diameter D = 15 in., following a well-rounded entrance. A turbulent boundary grows on the duct wall, but the flow is not yet fully developed. Assume that the velocity profile in the boundary layer is u/U = (y/δ)1/7. The inlet flow is U = 50 ft/s at section ①. At section ②, the boundary-layer thickness is δ2 = 4 in. Evaluate the static gage pressure at section ②, located at L = 20 ft. Find the average wall shear stress.
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Chapter 9 Solutions
Fox And Mcdonald's Introduction To Fluid Mechanics
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