Fox and McDonald's Introduction to Fluid Mechanics
9th Edition
ISBN: 9781118912652
Author: Philip J. Pritchard, John W. Mitchell
Publisher: WILEY
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Textbook Question
Chapter 9, Problem 20P
A flow of 68°F air develops in a flat horizontal duct following a well-rounded entrance section. The duct height is H = 1 ft. Turbulent boundary layers grow on the duct walls, but the flow is not yet fully developed. Assume that the velocity profile in each boundary layer is u/U = (y/δ)1/7. The inlet flow is uniform at V = 40 ft/s at section ①. At section ②, the boundary-layer thickness on each wall of the channel is δ2 = 4 in. Show that, for this flow, δ* = δ/8. Evaluate the static gage pressure at section ①. Find the average wall shear stress between the entrance and section ②, located at L = 20 ft.
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Chapter 9 Solutions
Fox and McDonald's Introduction to Fluid Mechanics
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