In this work a multibody collision model, amenable to large-scale computation, is developed to simulate a jet of near-field grains impinging on a surface. This model is developed by computing momentum exchange for grain–grain and grain–surface interactions. The grain–grain interactions consist of collisions as well as near-field interactions. The analysis of these flows is separated into three components: (1) volume averaged quantities; (2) average surface tractions; and (3) average outflow conditions. For the surface stress calculations, parametric studies are performed on the properties of the surface and the grains through their coefficients of restitution, the strength of the near-field interactions, and the angle of attack of the jet. For the outflow calculations the flux of momentum through the simulation space is performed for varying near-field forces between the grains and varying degrees of surface roughness.

In this work a multibody collision model, amenable to large-scale computation, is developed to simulate material removal with particulate flows. This model is developed by computing momentum exchange to account for different force interactions: (1) particle–particle interaction, (2) particle–fluid interaction, and (3) particle–surface interaction. For the particle-fluid interaction, a velocity field for the fluid is assumed to be known, and the drag force on the particles is computed from this field. In the particle–surface interaction, the Boussinesq solution for a point load on an elastic half-space is used along with the von-Mises yield criterion to determine the amount of material removed. Employing thismodel, inverse problems are then constructed where combinations of the abrasive particle size, the particle size distribution, the flow velocity, etc., are sought to maximize the efficiency of the process. A genetic algorithm is used to treat this inverse problem, and numerical examples are given to illustrate the overall approach.