Numerical Analysis of Hypervelocity Solid-Solid Impacts by Means of Improved SPH Method Using New Particle Generation and Particle Reducing Techniques.

Abstract

In the numerical simulation of hypervelocity impacts (HVIs) by means of a conventional SPH method, the loss of interactions amongthe particles causes numerical fractures. To prevent the numerical fractures, a 2-dimensional SPH method is improved usingnew particle generation and particle reducingtechniques. In the new particle generation technique, new particles are generated in the case when the area with no particles or the distance between the adjacent particles exceeds a certain value. In the particle reducingtechnique, which is used to avoid the overabundance of particles, two particles approachingeach other are combined to one when the distance between them attains a certain value. The perpendicular HVIs of a polyethylene projectile on an aluminum plate target are simulated numerically. Through the numerical results, it is shown that the improved SPH method can prevent effectively the numerical fractures without the overabundance of particles. The responses of oblique HVIs are also shown.