| Mon September 19th 2016 16:00 – 16:30 ZH286 | Seminar | DNS of ring vortex collisions Rodolfo Ostilla Mónico |
Details:We numerically simulate the ring vortex collision experiment of Lim and Nickels (Nature, 357:225-227, 1992) in an attempt to understand the rapid formation of very fine scale turbulence (or 'smoke') from relatively smooth initial conditions. Reynolds numbers of up to $Re=\Gamma/\nu=7500$, where$\Gamma$ is the vortex ring circulation and $\nu$ the kinematic viscosity of the fluid are reached, which coincide with the highest Reynolds number case of the experiments. Different perturbations to the ring vortex are added, and their effect on the eneration and amplification of urbulence is quantified. The underlying dynamics of the vortex core is analyzed, and compared to the dynamics arising from a simple Biot-Savart filament model for the core. | ||
