Vorticity Production at Fluid Interfaces in Two-dimensional Flows

Abstract

This work revisits the production of vorticity at an interface separating two immiscible incompressible fluids. A new decomposition of the vorticity flux is proposed in a two-dimensional context which allows to compute explicitly such a quantity in terms of surface tension $\sigma$, viscosity $\mu$ and gravity $g$. This approach is then applied in the context of gravito-capillary waves. It leads to analytical results already known but from a new perspective, provides some quantitative predictions at short time that can be a good test for numerical codes. Finally it is a mean to obtain a qualitative understanding of direct numerical simulation results.