Later stages of transition of an airfoil boundary layer flow excited by a harmonic point source

摘要

Laminar-turbulent transition induced by a harmonic point source disturbance is investigated in a flat-plate boundary layer with adverse pressure gradient using Direct Numerical Simulation based on the complete three-dimensional Navier-Stokes equations for incompressible flow. Thus Tollmien-Schlichting waves of a single frequency and a large number of obliqueness angles are stimulated and propagate downstream simultaneously, undergoing amplification by primary and subsequent instability, and eventually lead o breakdown of the laminar flow. The attention of this work is directed to the non-linear stages and final breakdown of the disturbed laminar flow.