Numerical study of mechanisms of boundary-layer transition after a separation bubble

Large-eddy simulation has been employed to study boundary layer transition on a flat plate immediately following a separation bubble induced by a change of curvature of the surface. The geometry is a flat plate with a semi-circular leading edge. The simulated results are compared with the available experimental data. The separation bubble at the leading edge is unstable and plays an important role in triggering transition for low or zero free stream turbulence. Data from the simulation has been gathered which allows us to extract all terms In the derived equations for the Reynolds stresses. Aspects of these balances are presented which may allow new insights into the physical mechanisms at work.