Viscous interaction between the boundary layers of a plane surface and a protruding vertical plate

The three-dimensional laminar incompressible flow near the corner formed by a vertical plate protruding at a distance L behind the leading edge of a horizontal plate is studied both analytically and numerically. It is treated as a singular perturbation problem. A systematic matching procedure is developed and applied to determine the flow in the different regions. A solution is found for the first and second order potential flow, and for the first and second order boundary layers. Due to flow separation on the horizontal boundary layer and the parabolic nature of the boundary layer equations, the calculation of the cross flow velocity right to the vertical wall becomes extremely difficult. However, a local examination of the fluid motion near the wall intersection shows the formation of a vortical structure characterized by Moffatt's eddies.