Explicit force model for discrete modelling of elliptical particles

In discrete element method (DEM), the calculation of the contact force between non-spherical particles always needs to numerically solve a set of higher order equations. We propose a method to develop explicit force models based on the orientation discretised force database and Fourier series. The method is applied to two-dimensional elliptical particles as the first trial. The results obtained by the explicit force model show good agreement with those by the finite element model. The explicit force model provides a simple, stable and accurate solution for DEM and will also be helpful to the theoretical analyses that require explicit equations.