Boundary Layer of a Flat Plate

This chapter derives flat plate frictional coefficients for laminar flow. A flat plate does not force the fluid to change course. Therefore, the exterior flow speed will be maintained everywhere outside the boundary layer. Based on his observations, Prandtl suggested that the basic shape of the velocity distribution remains approximately the same for increasing x-position along the boundary layer. It is simply stretched in y-direction. If a simple equation for the velocity distribution can be derived from measurements, the equation can be solved for the wall shear stress. Having an expression for the velocity distribution across the boundary layer enables us to compute the boundary layer thickness. Having found an expression for the thickness of a laminar boundary layer, one can compute the remaining boundary layer characteristics and compare them with Blasius' more accurate results.