Abstract
A two-dimensional unsteady laminar flow is numerically simulated when a pair of rectilinear vortices translates perpendicularly to a non-slip infinite plane wall in an incompressible viscous fluid. Using the finite difference approximation of 3rd order accuracy the governing vorticity and streamfunction equations are discretized and the fiow is numerically integrated with Re=5000 and 10000 subject to the appropriate boundary conditions from the initial state prescribed. The Reynolds number Re is the circulation of the vortex divided by the kinematic viscosity of fluid. The illustration of the calculated results simulates well the rebounding of the primary vortex and the motion of the secondary vortex which is released by the interaction of the primary one with the boundary shear layer. The stagnation pressure is also evaluated, whose magnitude is observed to be considerably influenced by the presence of the secondary one.
