An enhanced semi-implicit particle method for simulating the flow of droplets with free surfaces
An enhanced semi-implicit particle method for simulating the flow of droplets with free surfaces
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DOI：
10.1016/j.cma.2021.114338
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发表时间：
2021-11
影响因子：
7.2
通讯作者：
Guangtao Duan;M. Sakai
中科院分区：
文献类型：
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作者：
Guangtao Duan;M. Sakai
在无网格粒子方法中，自由表面表面张力的精确模拟一直是一个具有挑战性的问题。最近，Matsunaga等人。(2020)在解决这一问题上向前迈出了重要的一步，引入了移动曲面网格来表示2D中的自由曲面边界。然而，曲面网格使得将该方法扩展到3D以及处理自由曲面中的拓扑变化变得困难。本研究旨在将这一方法推广到3D，并通过仔细检测自由表面粒子来恢复模型模拟拓扑变化的能力。在这种情况下，关于波动的自由表面边界和自由表面与壁面边界的动态相交的问题就产生了。为了解决这些问题，提出了一种新的粒子在表面法线方向上的移位方法，以减少自由表面粒子的起伏。提出了一种新的接触角模型来计算自由表面与壁面边界的交点。在此基础上，发展了一种适用于三维可能存在拓扑变化的液滴动力学的增强型粒子方法。8个数值算例验证了所提出的方法，并证明了新的粒子移位技术的增强。
The accurate modeling of the surface-tension on free surfaces remains a challenging problem in meshfree particle methods. Recently, Matsunaga et al. (2020) have made an important step forward toward addressing this issue by introducing a moving surface mesh to represent the free-surface boundary in 2D. However, the surface mesh makes it difficult to extend this methodology to 3D and to treat topological changes in free surfaces. This study aims to extend this methodology to 3D and restore the capability of the model to simulate topological changes by carefully detecting the free-surface particles. In this situation, the problems regarding fluctuated free-surface boundaries and the dynamic intersection of a free surface with a wall boundary arise. To resolve these problems, a new particle shifting method in the surface normal direction is proposed for the free-surface particles to reduce fluctuations. A new contact angle model is proposed to compute the intersection point of a free surface and a wall boundary. In this manner, an enhanced particle method suitable for simulating the dynamics of liquid droplets with possible topological changes in 3D is developed. Eight numerical examples verified the developed method and demonstrated the enhancement of the new particle shifting technique.