A Novel Coupling Method for Unresolved Cfd-Dem Modeling

•A novel coupling method between the Eulerian CFD model and the Lagrangian particle model is developed.•The study is focused on the point-particle model to flow interaction when the cell size is smaller than the particle size.•Filtering the fluid information and smoothing the particle information are both considered.•The diffusion-based method is used to optimize computing efficiency and parallel performance.