Drop impact on a solid surface at high velocity

Drop impacts are usually studied for impact velocities up to about 5 m/s. We have constructed a new facility where we can, in a controlled manner, reach much higher impact velocities up to 23 m/s. In this way we can generate Reynolds ~ 10⁵ and Weber ~ 4 x 10⁴ . Using water/glycerin mixtures we can systematically vary the Reynolds number over three orders of magnitude, while keeping the Weber number very large, thereby reaching new corners of parameter space. Our focus is on the lamellar splashing, which we observe with up to 5 million frames per second, using a Kirana-5M video camera. The lamellar thickness reduces greatly at the highest velocities, while its jetting velocity reaches 400 m/s, or near 20 times the impact velocity. We highlight the importance of the bottom radius of curvature of the drop at first contact, especially when the ambient pressure is varied.