A tlat plate of length L and height d is placed at a wall and is parallel to an approaching boundary layer, as in Fig. .Assume that the flow over the plate is fully turbulent and that the approaching flow is a one-seventh-power law: и(у) — U Using strip theory, derive a formula for the drag coefficient of this plate. Compare this result with the drag of the same plate immersed in a uniform stream U,. -L- y = 6 / и(у)

A tlat plate of length L and height d is placed at a wall and is parallel to an approaching boundary layer, as in Fig. .Assume that the flow over the plate is fully turbulent and that the approaching flow is a one-seventh-power law: и(у) — U Using strip theory, derive a formula for the drag coefficient of this plate. Compare this result with the drag of the same plate immersed in a uniform stream U,. -L- y = 6 / и(у)

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.

Chapter5: Analysis Of Convection Heat Transfer

Section: Chapter Questions

Problem 5.24P: Engine oil at 100C flows over and parallel to a flat surface at a velocity of 3 m/s. Calculate the...

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Prob.7. A smooth flat plate of length 5 m and width 2 m is moving with a velocity of 4 m/s in stationary air of density 1.25 kg/m and kinematic viscosity 1.5 x 10-5 m2/s. Determine thickness of the boundary layer at the trailing edge of the smooth plate. Find the total drag on one side of the plate assuming that the boundary layer is turbulent from the very beginning.
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A square flat plate with sides of length L 2m and a negligible thickness (out of the page) is held stationary in a stream of air that is moving steadily at standard conditions past the plate with a speed U = 10 m/s that is uniform except for the boundary layers. Assume the plate is oriented so that only friction drag is important. Determine the drag coefficient for this plate. Answer: CD, ≈ 0.003 = U L-
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