2002 年 68 巻 665 号 p. 132-138
The Smoothed Particle Hydrodynamics (SPH) method is an evolving numerical technique for modeling many transient dynamic problems of large deformation, including high and hypervelocity impact problems. The SPH method employs no spatial mesh. The absence of a mesh leads to some nice features such as the ability to handle large distortions in a Lagrangian frame and consider the effects of voids. However, in the SPH calculation, numerical fracture can occur when the interaction among the particles disappears as a result of increasing distance among them. In this paper, the SPH method is improved in order to prevent the numerical fracture. The improvement of the SPH method is based on the concept that new particles are generated in the numerical fracture space. The improved SPH method is applied to analyze hypervelocity impact problems. The numerical results show that the present method can generate new particles without large influence on the surrounding region and prevent the numerical fracture effectively.