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液态泡沫由大量气泡密集堆积在微量表面活性剂溶液中形成,具有高度有序的结构和独特的流变特性,是典型的复杂系统,与常见的固体泡沫和多孔介质截然不同.影响液态泡沫结构和流变特性的惟一重要因素就是泡沫内部的微量液体.这些微量液体受重力与毛细管力会在泡沫通道上(柏拉图通道和节点,亦即Plateauborder和vertex)发生渗流,柏拉图通道和节点也往往同时发生几何拓扑变化,释放表面能.该自组织过程是由流体耗散趋于极小和泡沫表面能趋于极小两种机制的相互协调控制的.重力会影响流体耗散趋于极小趋势的强弱,进而造成不同的自组织过程,影响泡沫内的渗流.本文模拟了Hele-ShawCell内两维液态泡沫(大小为12cm×14cm×3mm)在8种重力加速度(从g=9.8m/s2到g=0m/s2)下点输入的强制渗流,发现在竖直和水平方向的渗流波传播位置与时间的关系很好地符合幂函数形式,指数分别为0.536+5.29×10?3g和0.479?7.27×10?3g,在不同重力下两者之和接近常数1.015,该结果将有助于进一步分析泡沫内部的协调机制.
Liquid foam, formed by the dense accumulation of large number of bubbles in the solution of surfactant, has a highly ordered structure and unique rheological properties. It is a typical complex system, which is very different from the common solid foam and porous media. And the only important factor in the rheological behavior is the amount of liquid in the foam that can seep through the foam channels (Plato channels and nodes, Plateauborder and vertex) by gravitational and capillary forces, and Plato channels and nodes at the same time The geometric topological changes occur and the surface energy is released.The self-organization process is coordinated and controlled by the minimization of fluid dissipation and the minimization of the foam surface energy.The gravity will affect the tendency of fluid dissipation to a minimum , Which leads to different self-organization processes that affect the seepage in the foam.This paper simulates the effect of two-dimensional liquid foam (size 12cm × 14cm × 3mm) in Hele-ShawCell on eight kinds of gravitational accelerations (from g = 9.8m / s2 to g = 0m / s2), we find that the relationship between the vertical and horizontal seepage wave propagation locations and time is in good agreement with the power function form The numbers are 0.536 + 5.29 × 10 -3 g and 0.479 × 7.27 × 10 -3 g, respectively. The sum of the two is close to 1.015 under different gravities, which will be helpful to further analyze the coordination mechanism inside the foam.