Free Surface Signature of Unsteady, Two-Dimensional Vortex Flows.

摘要

The interaction of two-dimensional vortex flows with a free surface is studied numerically using a combined vortex/boundary integral technique. The vorticity is modeled as point vortices, vortex sheets and finite area vortex regions. Two problems are studied in considerable detail, the large amplitude Kelvin-Helmholtz instability of a submerged shear-layer and the head-on collision of a vortex pair with the free surface. The surface deformation is controlled by a Froude number, based on the vortical motion, and the geometrical parameters describing the initial vortex configuration. Large Froude numbers generally lead to strong interactions for sufficiently shallow vortices.