A new contact liquid dispersion model for discrete particle simulation

In wet granulation and particle coating, it is important to accurately predict the liquid dispersion for process optimisation and quality assurance. In this work, a new contact dispersion model is proposed by taking into account the partial wetting of particle surfaces, which is incorporated into the Discrete Element Method (DEM). In the proposed model, individual particle surfaces are sub-divided and the liquid redistribution between these sub-divided surfaces are tracked with time. The proposed model is applied to simulate a spray drum where liquid is sprayed to initially dry particles, and the liquid dispersion rate is compared with the results obtained from the Shi and McCarthy model (Shi and McCarthy, 2008), which is one of the pioneering models for contact liquid dispersion in DEM. It is found that the Shi and McCarthy model gives faster liquid dispersion when highly viscous liquid is used, whilst the results are largely comparable in the low viscosity case.