Influence of holdup on gas and particle flow patterns in a spiral jet mill

Particle size reduction in spiral jet mills is induced by high velocity gas jets, causing interparticle and particle wall collisions leading to breakage. Despite extensive research on the design operational parameters, underlying mechanics of still poorly understood. Discrete Element Method Computational Fluid Dynamics are used here analyse fluid motions. A fast shearing dense bed formed wall, with a transition lean phase towards centre mill. This necessitates four-way coupling interactions for analysis. It shown that increasing depth reduces tangential proximity classifier, as momentum exchanged circulating particles. The energy dissipation through occurs mainly along surface front grinding nozzles.