Numerical research on kerf characteristics of abrasive waterjet machining based on the SPH-DEM-FEM approach

Abrasive waterjet machining has been widely used because of flexibility, but the cutting accuracy is difficult to ensure due to the lack of dynamic analysis in the forming process of the kerf. In this paper, a coupled SPH-DEM-FEM method is proposed to predict the cutting qualities of the abrasive water jet machining under different process parameters and reveal the mechanism of the kerf formation. Compared with previous simulation methods, the new simulation method has advantages in the simulations for long-term water jet cutting. The abrasive particles and waterjet particles are continuously generated during calculations to reduce the model size and raise the calculation efficiency. The discrete element method (DEM) is utilized to characterize the flow of abrasive particles, which follows the Gaussian distribution. The collisions of non-spherical particles are concerned by the friction factors. The water flow with large deformation is expressed in the smoothed particle hydrodynamics (SPH) method. And the erosion contact is set between particles and the target. Finally, experiments are conducted to verify the authenticity of the simulation model. The cutting depths and kerf top widths obtained by the simulations are consistent with the experimental results.