Particle Contact Model For Cfd-Dem Simulations

We investigate the characteristics of several soft sphere contact models commonly used in CFD-DEM simulations. In the linear-spring-dashpot (LSD) model, the contact force acts as an attractive force rather than a repulsive force near the end of the collision, and a non-zero force acts even when the overlap is zero. By contrast, the Flores model provides the most physically relevant results, with the contact force always acting as repulsive force. However, the Flores model has a disadvantage in that the restitution coefficient specified in the model does not exactly coincide with that obtained from the result, particularly when the restitution coefficient is small. The Kuwabara-Kono model shows an intermediate characteristic between the LSD and Flores models in terms of the contact force and restitution coefficient.