模拟二维水下爆炸问题的光滑粒子(SPH)方法

水下爆炸涉及两相流,是一个动边界的问题,迅速变化的气-液交界面给传统的基于网格的数值方法带来了严重的挑战。SPH法是一种拉格朗日方法,该方法可以准确且有效地捕捉气-液交界面。论文应用光滑粒子(SPH)法来模拟水下爆炸过程,特别给出了光滑长度的选取方法和优化算法。最后,通过两个算例验证该方法,数值模拟结果表明,光滑粒子法在处理水下爆炸这样的大变形和强非线性问题方面具有精度高、耗时少、数值稳定等优点。

SPH simulation of two-dimensional underwater explosion

Underwater explosion,involving gas-liquid two-phase flows,is a problem of dynamic boundary.Numerical simulation of underwater explosion problems is a challenge for traditional mesh-based numerical methods due to the inherent feature such as moving interface.As a Lagrangian method,SPH can track the moving interface between the gas produced by the explosion and the surrounding water effectively.In this paper,we apply SPH to simulate the process of underwater explosion.Some important improvements are made in our SPH code to suit for the needs of simulating underwater explosion especially in optimizing the smoothing length.The results obtained from SPH show that the present method can successfully simulate large deformation or strong non-linear problem such as underwater explosion at high accuracy with less computational effort,and numerical stability as well.