An experimental study of the antibubble formation by a single drop impact on an identical liquid bath is presented. With the increase in the impact velocity, different phenomena are observed and classified into four regimes: No droplet, Single droplet, Double droplets, and Antibubble formation. In fact, the Antibubble formation is part of the Double droplets regime. A high-speed drop impact leads to the formation of a thick jet, which subsequently pinches into two main droplets named as the primary droplet and the secondary droplet. The secondary droplet first impacts on the liquid surface, while the primary droplet then falls back and pushes it into the liquid bath, generating an antibubble. The detailed dynamics is presented, and the critical conditions for antibubble formation are introduced. This work should benefit the controllable generation of antibubbles and stimulate the future applications in practice.

中文翻译：

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通过单滴撞击自由表面形成防气泡

提出了通过对同一液体浴进行单滴撞击来形成防气泡的实验研究。随着冲击速度的增加，观察到不同的现象并将其分为四种状态：无液滴，单液滴，双液滴和防气泡形成。实际上，防气泡形成是双液滴方案的一部分。高速滴落冲击导致形成厚的喷射流，随后将其喷射成两个主要液滴，分别称为初级液滴和次级液滴。次要液滴首先撞击液体表面，而次要液滴然后向后下落并将其推入液槽中，从而产生防气泡。介绍了详细的动力学过程，并介绍了防气泡形成的关键条件。