A validated numerical scheme for simulating incompressible free surface flows has been used to investigate the formation of vortex rings that result from the impact of a water drop onto the surface of a deep water pool. Simulations of a 2.9mm drop impacting at 0.8m/s and 2.5m/s indicates new features of vortex ring formation that have not been reported before. For impact at 0.8m/s, numerical results predict the formation of two vortex rings during collapse of the crater that follows impact. This is significant since previous experimental studies assumed that a single impact produced a single vortex ring. Numerical results for impact at 2.5m/s predict the formation of a small vortex ring during the initial growth of a vertical Rayleigh jet. If confirmed, the formation such vortex rings disagrees with existing theories that vortex rings do not occur for Weber numbers greater than 8.
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