Laminar boundary layer between two planes perpendicular to each other (Q581136)

We obtain a third-order approximate solution for the laminar boundary layer between two planes perpendicular to each other. In boundary layer equations, the viscous and the inertial terms have the same quantity step. In this paper, at first, supposing that the inertial terms are bigger than the viscous terms, we solve the boundary layer equations, and then we suppose that the viscous terms are bigger than the inertial terms. At last, we take the mean value as the valid solution of the boundary layer equations.