基于改进PIB搜索法的SPH方法在高速冲击模拟中的应用

Application of SPH with modified PIB search algorithm to high-velocity impact simulation

SPH方法在高速冲击模拟中具有优势并已得到广泛使用,但其相邻粒子搜索非常耗时,其实际应用受计算效率制约。为了提高计算效率,采用一种改进的Point-In-Box(PIB)搜索法进行相邻粒子搜索。利用基于该相邻粒子搜索法的SPH方法,模拟了泰勒杆、平头弹撞击钢板等一系列高速冲击问题。计算结果表明:SPH方法能有效地模拟冲击过程中的大变形、绝热剪切破坏等现象,模拟结果与实验结果符合良好;同时,与传统相邻粒子搜索法相比,应用改进的PIB搜索法使SPH方法的计算效率得到明显提高。

SPH method has many advantages and is widely used in high-velocity impact simulation,but its practical applications are still restricted by its low computational efficiency due to the time-consuming neighboring particle search（ NPS）. To improve its efficiency,a modified point-in-box（ PIB） search algorithm was employed to determine neighboring particles. By using the SPH with modified PIB search algorithm,a series of impact problems,including Taylor tests and steel plate impacted by blunt projectile,were simulated. The calculated results indicated that SPH can effectively simulate large deformations and adiabatic shear failure during the impact processes,and give results in good agreement with experiments. The results also showed that the modified PIB search algorithm can make the SPH method achieve a much better efficiency than a traditional search algorithm.