Experimental Research Of Discrete Body Around Cylinder In The Ultra-Fine Vibration Mill Cylinder

With the growing development of modern high-tech industry, new materialsindustry and mineral processing technology, there are increasing demands far varioustype of ultra-fine powder products in metallurgy, mining, chemicals, buildingmaterials, medicine crud other related areas, moreover, there are higher requirementsfar the quality of the raw material powder, such as fine and ultra fine particles, strictparticle size distribution and specific particle shape. Based on discrete grindingmedium group (grinding medium and material) dynamics model, aiming to theshortage of particle size limit with the vibration mill (micron), that is bottleneckproblem of no refinement. Study the following points: Compared with the method ofstudy viscous fluid, crushed material is deemed to discrete body (powder). With theincreasing of discrete body movement speed, the model of low speed motion withdiscrete body was build. Through the shear test methods, the viscosity coefficient(shear) of crushed material will change and then the change law of shear stress wasstudied that the discrete body under the condition of different velocity. Aiming toobservation of shock, grinding, and shear with ultra-fine vibration mill grindingmedium to materials. Typical movement of discrete particles and discrete grindingmedium were to be analyzed, then be abstract summarizes, draw lessons fromhydromechanics, movement and regularity of ideal discrete body around cylinderwere investigated. on this basis, through to the three different materials(plaster、calcite、quartz) around cylinder in the wind tunnel experiments.The results show that:(1) In the motion process of discrete body, shear forcebecome large with increasing speed, shear force is a key point to break the particlesize limit.(2) Research method of viscous fluids can be used to describe the grindingprocess of ultra-fine vibration mill granulate discrete body. The test result show thattheoretical curves and experimental curves of stress distribution on the cylindersurface is the same in a certain range, to show that the method has certainfeasibility.(3) Discrete body of pulverization occurs mainly in the discrete whirlpoolarea that is Reynolds stress area. In this area, momentum exchange between discretebodies, discrete body get energy to broke discrete bodies, Reynolds stress increase, accelerate the process of crush discrete body in the whirlpool area.(4) Used on thediscrete grinding medium group dynamics model, bit degeneration and time-varyingof discrete grinding medium group (grinding medium and material) are perfect, it canaccurate explain law of motion and the relationship between discrete body of grindingmedium, this is fundamentally different from previous studies of single discrete body.This research not only helps to enrich grinding theory of the vibration mill, not onlyhas important guiding significance to further improve powder process skills, and toimprove reasonable and high value-added utilization far industrial mineral resources.