Flow Around a Leading Edge Slat: Part II — Cove Flow Dynamics via Snapshot POD

The dynamics of flow within the cove of a leading edge slat has been investigated using Proper Orthogonal Decomposition by the method of snapshots. The shear-layer that originates from the slat cusp contains a large proportion of the turbulent kinetic energy within the flow. Reconstructions performed with the first 10 POD eigenmodes illustrates that several smaller regions of vorticity persist within the shear-layer. Depending on the Reynolds number and the angle of attack, the shear-layer can impinge upon the leading edge of the main wing element, roll up within the slat cove, or be ejected through the gap between the slat trailing edge and the leading edge of the wing. This unsteady impingement of both the shear-layer, and the smaller features within the shear-layer could result in a very strong acoustic dipole source.