Numerical simulation of the penetration of granite at wide-range velocities with a new SPH method

A new Smoothed Particle Hydrodynamics (SPH) method is used to simulate the deformation of granite at large strain and high strain rates during penetration in the study. In order to describe the nonlinear deformation and failure characteristics of rock and metallic materials, Holmquist-Johnson-Cook (HJC) constitutive and damage models were applied to granite plates. In addition, Johnson-Cook (J-C) constitutive model and Gruneisen equation of state were applied to the projectile body, respectively. The projectile body and granite plates were discretized into Lagrangian particles during simulation. Through the simulation of three-dimensional penetration process of granite plates by self-made program at the initial penetration velocity of 0∼4000m/s, this article compares and analyzes the penetration results of different projectile bodies, fitting the curve of the penetration depth versus the initial penetration velocity in solid, semi-fluid and fluid penetration fields. The numerical results show the relationship between the penetration depth and the initial penetration velocity in the range of 0∼4000m/s. As the initial penetration velocity increases, the penetration depth shows an increasing trend in the solid penetration area (V0 < 1421m/s), and a decreasing trend in the semi-fluid penetration area (1421m/s < V0 < 1700m/s). When the initial velocity comes to the range of V0 > 1700m/s, the penetration is in a complete fluid penetrating state, and the penetration depth increases nonlinearly with the initial penetration velocity. The increasing curve gradually flattens out if V0 > 3000m/s, and reaches the peak value.