Spinning Twisted Ribbons Formed in the Corona Splash of Drop Impact on Liquid Film*

When a liquid drop impacts a thin liquid film at high speed, it generates a thin corona sheet, followed by a splash. The thin corona sheet spontaneously ruptures, forming multiple holes as its thicknesses rapidly decreases. These ruptures result in many secondary droplets. In this study, we reveal an interesting underlying mechanism. We find that the ruptured sheet evolves into structures that resemble spinning twisted ribbons before the formation of ejecta. We develop a simple model to explain this phenomenon and validate it with experimental data. Our findings provide new insights into the mechanisms of splashing.