SPH方法在溃坝数值模拟中的应用

Application of SPH method to numerical simulation of dam-break

光滑粒子流体动力学(SPH)方法是一种纯拉格朗日无网格方法,适用于模拟波浪破碎、高速水流、高速冲击碰撞等瞬时极大变形的问题。介绍了SPH方法的基本原理、核函数及离散格式的控制方程、边界处理方法等,建立了数值水槽模型,验证了模型的有效性。应用SPH方法模拟了二维溃坝问题,考虑了添加无孔障碍物和有孔障碍物的2种情形,将模拟得到的结果进行对比分析。结果表明,SPH方法能够很好地捕捉流体自由面变形、飞溅及融合现象,在一定程度上有孔障碍物有更好的消能效果。

Smoothed particle hydrodynamics （SPH） method is a fully Lagrangian meshless method, which is available to simulate the problems with instantaneous very large deformation, such as wave cracking, high-speed water flow, high-speed impact and collision. The basic principle, kernel function, discretization of governing equations and boundary treatment of SPH method are introduced, a numerical flume model is constructed and its validity is verified. 2D dam-break problem under two cases is simulated respectively, i.e. obstacle with and without holes, and the computational results are compared and analyzed. It is demonstrated that the SPH method can nicely capture the variation of the free surface flow, the fluid fragment and coalescence, and to some extent, the energy dissipation effect is better when the obstacle has holes.