Problem 1. A smooth plate with length L = 3.0 m and width b = 0.90 m moves through still air at STP at a velocity of U = 4.5 m/s that is aligned with L. Calculate the following for a boundary layer that stays laminar and for one that trips to turbulent at the leading edge: (a) boundary layer disturbance thickness, 8, at æ = 0.5, 1.0, 1.5, 2.0, 2.5, and 3.0 m from the leading edge of the plate, (b) wall shear stress, Tw, at those æ- locations, and (c) friction drag, Fp,f, on one side of plate. (d) Calculate percent decrease in drag for laminar versus turbulent boundary layer.

Problem 1. A smooth plate with length L = 3.0 m and width b = 0.90 m moves through still air at STP at a velocity of U = 4.5 m/s that is aligned with L. Calculate the following for a boundary layer that stays laminar and for one that trips to turbulent at the leading edge: (a) boundary layer disturbance thickness, 8, at æ = 0.5, 1.0, 1.5, 2.0, 2.5, and 3.0 m from the leading edge of the plate, (b) wall shear stress, Tw, at those æ- locations, and (c) friction drag, Fp,f, on one side of plate. (d) Calculate percent decrease in drag for laminar versus turbulent 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.

Chapter5: Analysis Of Convection Heat Transfer

Section: Chapter Questions

Problem 5.49P

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