A cubic approximate velocity profile was used in Problem 5.12 to model flow in a laminar incompressible boundary layer on a flat plate. For this profile, obtain an expression for the x and y components of acceleration of a fluid particle in the boundary layer. Plot ax and ay at location x = 3ft, where δ = 0.04 in., for a flow with U = 20 ft/s. Find the maxima of ax at this x location.
5.12 A useful approximation for the x component of velocity in an incompressible laminar boundary layer is a cubic variation from u = 0 at the surface (y = 0) to the freestream velocity, U. at the edge of the boundary layer (y = δ). The equation for the profile is u/U =
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Fox and McDonald's Introduction to Fluid Mechanics
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