We study the dynamical behavior of droplets on a viscoelastic soft substrate. Using thin film approximation for the hydrodynamics and time-dependent Winkler’s substrate model, we show numerically how droplet growth depends strongly on the viscous damping characteristic of the substrate, leading to asymmetric stick-slip dynamics corroborated by experimental observations. Scaling arguments are presented to rationalize radial growth and the underlying substrate response to viscoelastic limits. Using an adjacent pair of inflating droplets, we report strongly diverse coalescence outcomes with non-linear coalescence times, including attraction, repulsion, and remarkably, a separation regime, within which the two droplets grow away from each other and remain separated due to intervening wetting ridges. Together, our results indicate strong interactions between the substrate and the droplet across viscoelastic and capillary timescales, with practical implications for smart surface engineering, condensation, and coalescence control.

中文翻译：

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粘弹性软基材上的液滴动力学：趋向聚结控制

我们研究了粘弹性软基材上液滴的动力学行为。使用流体动力学的薄膜近似和时间相关的温克勒基底模型，我们以数值方式展示了液滴生长如何强烈依赖于基底的粘性阻尼特性，从而导致实验观察证实的非对称粘滑动力学。提出了缩放参数以合理化径向生长和底层基材对粘弹性限制的响应。使用一对相邻的膨胀液滴，我们报告了具有非线性聚结时间的强烈不同的聚结结果，包括吸引、排斥和显着的分离机制，在该机制中，两个液滴彼此远离并由于介入润湿而保持分离脊。一起，