Numerical simulation of wet particle flows in an intensive mixer
Simulations of wet particle flow in an intensive mixer were conducted based on three-dimensional discrete element methods (DEM). Mikami capillary force model was introduced to mimic the complex effects of pendular liquid bridges in the granular flow. Lacey mixing index was adopted to evaluate the dynamic process of particle system. Experiments of intensive mixer tester were carried out for validating the simulation model during the mixing process. It was found that the blade torque increases with higher liquid fraction due to the damping action of capillary forces. Bigger particle size, high blade, and vessel speed can also increase the blade toque as the pronounced velocity fluctuation. Our results indicate the contact number decreases with higher blade speed and vessel speed, while it is little affected by the liquid fraction. The analysis of mixing quality shows that high homogeneity of particles distribution is obtained with higher blade speed and small particle size, while liquid fraction and vessel speed have little influence during the dynamic equilibrium stage.
Keywords: Intensive mixer, Particle mixing, Liquid bridge force, Discrete element method,