Prediction of coupled particle and fluid flows using DEM and SPH

• A transient fully coupled DEM + SPH is proposed for modelling multiphase flow.
• The method is stable and robust and highly effective at modelling complex flows.
• Mixing of fluid and particulates in a chute demonstrates transition from dry to wet.
• Differences in the magnitude of the coupling force occur for different correlations.
• Slurry and particle flow in the grinding and pulp chambers of a mill are predicted.

A coupled DEM (discrete element method) and SPH (smoothed particle hydrodynamics) method is used to predict the motion of the solid particles interacting with slurry flow. DEM simulates the motion of the coarser particulates while SPH simulates the slurry (water and finer particulates). This three dimensional method is demonstrated for multiphase mixing flow on a chute, in a central slice of a 36′ SAG mill and in a Hardinge pilot mill. It is shown to be robust and stable and able to predict complex coupled free surface particle and slurry flows including splashing with saturation levels varying from dry to fully saturated. It is suitable for prediction of multiphase flow in moving equipment including small scale structures such as classification grates.