IMPACTION AND REBOUND OF PARTICLES AT ACUTE INCIDENT ANGLES

When a particle impacts on a surface at an angle < 90-degrees, only the normal component of the impact velocity is usually considered to contribute to deformation. A new model has been developed in which the impact velocity tangential to the surface contributes towards lateral rotation during impact, and the remaining tangential kinetic energy and the stored elastic deformation energy provide the energy for particle rebound. Calculations with the model for conditions used in published experiments compare well with the data and explain observed dependencies. It was found that the rebound velocity and also the critical velocity, at which rebound starts, are strongly dependent on the incident impact angle. Aspects of the new model have been used to calculate and explain the performance of a newly developed particle bounce monitor.