Contact detection algorithms for DEM simulations of tablet-shaped particles

The shape of standard round tablet was represented by using the intersection of three spherical surfaces. Using this model, the contact criteria for tablet–flat surface and tablet–tablet contact were developed and were applied for tablet–tablet contact using a DEM simulation implemented in Matlab™ code. In addition, a high-speed digital imaging system was used to capture the images of one tablet hitting another fixed tablet anchored to a flat surface. Comparison of angular velocity showed good agreement between simulation and experimental results. The simulations were compared with alternative multi-sphere representations for the shape of the tablet and the results showed that the simulation times for 66- and 178-sphere representations were much larger than that for the tablet simulations. In addition, the simulation results for all the multi-sphere representations were significantly different from those of the tablet simulation.