The shape of a soft solid is largely determined by the balance between elastic and surface energies with capillarity becoming important at length scales smaller than the elastocapillary length, which approaches the millimeter scale for the softest hydrogels, leading to many new and surprising phenomena. This review is focused on describing recent experimental and theoretical progress on the deformations of soft solids due to capillarity in two-phase systems for both statics and dynamics. Relative to rigid solids, surface tension can lead to the rounding of sharp corners, wrinkling and creasing, and general morphological shape change of the static equilibrium configuration, beyond a critical elastocapillary number. With regard to dynamics, both surface tension and viscoelasticity affect wave number selection in a number of dynamic pattern formation phenomena in soft solids, such as elastocapillary-gravity waves, Rayleigh–Taylor instability, Plateau–Rayleigh instability, Faraday waves, and drop oscillations, all of which have direct analogs with classical hydrodynamic instabilities helping to interpret the relevant physics.

中文翻译：

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从静力学到动力学塑造毛细管固体


软固体的形状在很大程度上取决于弹性能和表面能之间的平衡，毛细作用在小于弹性毛细管长度的长度尺度上变得很重要，弹性毛细管长度接近最软水凝胶的毫米尺度，从而导致许多新的和令人惊讶的现象。本文的重点是描述在静力学和动力学的两相系统中由于毛细作用而引起的软固体变形的最新实验和理论进展。相对于刚性固体，表面张力会导致尖角变圆、起皱和折痕，以及静态平衡构型的一般形态形状变化，超过临界弹性毛细管数。在动力学方面，表面张力和粘弹性都会影响软固体中许多动态图案形成现象中的波数选择，例如弹毛细管引力波、瑞利-泰勒不稳定性、高原-瑞利不稳定性、法拉第波和液滴振荡，所有这些都与经典流体动力学不稳定性有直接的类似物，有助于解释相关的物理学。