# Vortex ring refraction at large Froude numbers - Physics > Fluid Dynamics

Vortex ring refraction at large Froude numbers - Physics > Fluid Dynamics - Descarga este documento en PDF. Documentación en PDF para descargar gratis. Disponible también para leer online.

Abstract: We have experimentally studied the impact of an initially planar axisymmetricvortex ring, incident at an oblique angle, upon a gravity-induced interfaceseparating two fluids of differing densities. After impact, the vortex ring wasfound to exhibit a variety of subsequent trajectories, which we organizeaccording to both the incidence angle, $\theta i$, and the interface strength,defined as the ratio of the Atwood and Froude numbers, $A-F$. For grazingincidence angles $\theta i \gtrsim 70$ deg. vortices either penetrate orreflect from the interface, depending on whether the interface is weak orstrong. In some cases, reflected vortices execute damped oscillations beforefinally disintegrating. For smaller incidence angles $\theta i \lesssim 70$deg. vortices penetrate the interface. When there is a strong interface, thesevortices are observed to curve back up toward the interface. When there is aweak interface, these vortices are observed to refract downward, away from theinterface. The critical interface strength below which vortex ring refractionis observed is given by $\log {10}{A-F}= -2.38 \pm 0.05$.

Autor: Kerry Kuehn, Matthew Moeller, Michael Schulz, Daniel Sanfelippo

Fuente: https://arxiv.org/