Laminar Boundary Layer Interaction With an Unsteady Passing Wake

Abstract

An investigation was conducted to study the unsteady effects of a moving wake as it passes over a laminar boundary layer in a stagnation region. Arguments are presented showing that in this region, the wake-induced unsteadiness may be treated, for the most part, as an inviscid, unsteady free stream, which impresses itself on the boundary layer flow. As a result, the boundary layer equations remain valid and, for relatively small oscillations, a solution to the equations may be obtained using standard perturbation techniques. A related experiment is then described and the results are examined in light of this analytical approach.