论文标题
在掉落的火山口倒塌过程中，动态过渡接近喷射奇异性
Dynamic transition approaching jetting singularity during the collapse of drop-impact craters
论文作者
论文摘要
了解从毛细管驱动到纯惯性焦点的动态过渡对于揭示从滴Impact-Impact山口产生的最奇异的微射流的机制很重要。本文中，我们研究了这些陨石坑的崩溃时的凹痕动力学，当滴度与池的不混溶液体不同时。参数空间比相同的液体要复杂得多，这揭示了复杂的化合物粉末形状。与通用的毛细血管惯性下降捏合方案相反，颈部半径为$ r \ sim t^{2/3} $，这是空气 - 迪姆普尔的纯惯性崩溃，描绘了$ r \ sim t^{1/2} $，对初始和边界条件敏感。因此，毛细管波可以将酒窝塑造成不同的塌陷形状。我们观察到在捏合前，从毛细血管惯性到纯惯性的动力学性质的清晰跨越。值得注意的是，对于奇异的喷射，跨界时间的发生得比韦伯数字不论要早得多。
Understanding the dynamical transition from capillary-driven to pure inertial focusing is important to revealing the mechanism underlying the most singular micro-jetting produced from drop-impact craters. Herein we study dimple dynamics from the collapse of these craters when the drop is of a different immiscible liquid than the pool. The parameter space is considerably more complex than for identical liquids, revealing intricate compound-dimple shapes. In contrast to the universal capillary-inertial drop pinch-off regime, where the neck radius scales as $R\sim t^{2/3}$, a purely inertial collapse of the air-dimple portrays $R \sim t^{1/2}$ and is sensitive to initial and boundary conditions. Capillary waves can therefore mold the dimple into different collapse shapes. We observe a clear cross-over in the nature of the dynamics from capillary-inertial to purely inertial immediately before the pinch-off. Notably, for singular jetting the cross-over time occurs much earlier, irrespective of the Weber number.
