Mon April 21st 2008 14:00 | Seminar | Axisymmetric collapse of bubbles and singular jets JosÃ© Gordillo Arias de Saavedra |

## Details:In this talk we analyze the final instants of axisymmetric bubble pinch-off in a low viscosity liquid. We find that both the time evolution of the bubble dimensionless minimum radius, $R_0(t)$, and of the dimensionless local axial curvature at the minimum radius, $2 r_1(t)$, are governed by a couple of 2D Rayleigh-like equations in which surface tension, viscosity and gas pressure terms need to be included for consistency. The stagnation flow structure existing in the local region surrounding the minimum bubble radius will permit to scale the velocities of the Worthington liquid jets that are usually ejected right after bubble pinch-off.A simplified model for the subsequent time evolution of the jet in terms of the superposition of a discontinuous line of sinks plus a point sink which moves at the same velocity as the base of the jet will be also discussed. |