Numerical simulation and experimental verification of the rock damage field under particle water jet impacting

By impacting and breaking rock with a particle water jet, particle impact drilling technology can accelerate the rate of penetration. To study the dynamic process, damage evolvements, and failure mechanisms of rock under the impact of a particle water jet, the smoothed particle hydrodynamics method (SPH) was coupled with the finite element method (FEM) to combine their advantages. Based on a stochastic algorithm, steel particles built by FEM were dispersed among water built by SPH to construct a new model of a particle water jet that can actually reflect the large-diameter and low-concentration features of the solid phase in a particle water jet. To verify the accuracy of the numerical simulation results, indoor experiments of a particle water jet impacting rock were carried out. The simulation results were demonstrated by experimental studies, which indicated that the SPH-FEM coupled method was able to simulate the rock-breaking process under a particle water jet. The simulation results revealed that rock fragmentation was achieved due to the impact dynamic load and rock softening caused by the stress wave and that the scope of the stress wave had a distinct partial effect.