Study On Grinding Effect Of Large Vertical Screw Stirring Mill That Based On Fluid-Structure Interaction

With the development of China's industry to large-scale and high-efficiency,the design demand and use demand of large-scale vertical screw stirring mill are gradually increasing.In this paper,combined with the school enterprise cooperation project "simulation analysis and optimization design of large vertical spiral stirring mill",the grinding effect of large vertical spiral stirring mill is studied.This paper summarizes the research background,research significance and development status of large vertical spiral stirred mill,including the development status of grinding equipment and stirred mill,the structure and characteristics of vertical spiral stirred mill,and the research status at home and abroad.The grinding mechanism and key parameters of vertical screw stirring mill are analyzed.Grinding mechanism includes working principle,grinding theory,grinding medium stress intensity,grinding energy consumption and so on.The key parameters include structure parameters such as screw diameter,lift angle and lead,as well as characteristic parameters such as stirring speed and grinding medium properties.By using the fluid structure coupling simulation analysis method,the dynamic simulation model of vertical spiral stirring mill is constructed,and the dynamic simulation method suitable for large vertical spiral stirring mill is formed.The effectiveness of this method is verified by comparing with the actual mill data.The grinding process of the mill and the factors affecting the grinding effect are analyzed by dynamic simulation.Based on the time-based population balance model,a mathematical model for predicting the product particle size distribution of vertical screw stirring mill was established.The grinding experiment of the mill verified the validity of the model,and the parameters of the model were fitted under common feeding conditions.At the same time,the influence of process parameters on grinding effect is analyzed through the experimental results.This paper analyzes the design process of the important parameters of the large vertical spiral stirring mill.According to the preliminary design scheme of a large vertical spiral stirring mill,the dynamic simulation and the prediction of the particle size distribution of the grinding product are carried out.After that,the variable parameters of the mill are defined and optimized.Through the dynamic simulation of the optimized model,it is ensured that it is in a good grinding state.The particle size distribution of the grinding product of the optimized mill is predicted.Compared with that before optimization,the grinding effect is greatly improved.Finally,a set of analysis and optimization methods for grinding effect of large vertical spiral stirring mill is formed,which provides a reference for the design of large vertical spiral stirring mill.