Study On The Application Of Coanda Effect In The Sepiolite Powder Jet Classification

Sepiolite powder jet classification device is a high pressure air flow through the nozzle carrying sepiolite powder into the classification area,use the function of coanda block and make jet coanda effect and the realization of sepiolite powder particle size grading device.Based on the coanda effect of sepiolite superfine powder,the combination of different kinds of nozzles with different curvature of coanda block is optimized,and under the condition of different process parameters,analyzes the flow characteristics of the sepiolite powder of different particle size,and has set up a platform experiment,sepiolite powder jet classification experiment was carried out,test and verify the reliability of the simulation accuracy.This dissertation mainly focuses on the following aspects:(1)Theoretical analysis of Sepiolite powder jet classification.Based on gas-solid two-phase flow theory and jet coanda classification theory,the stress analysis of a single sepiolite particles,and discussed the key factors affecting jet coanda effect,provide theoretical guidance for further research.(2)Numerical simulation analysis of key components in the jet classification area.Firstly,the material characteristics of sepiolite particles were tested to provide data for subsequent simulation.Then,COMSOL Multiphysics simulation software was adopted to analyze the performance of the nozzle based on the material characteristics of the sepiolite powder and the influence of different curvature of coanda blocks.In the end,with the effect of attaching to the wall as the index of the superfine powder of the sepiolite,the optimal combination of different nozzle and wall surface curvature radius of 200mm was optimized to find the optimal combination of nozzle and coanda block.(3)Analysis of the flow characteristics of sepiolite powder in the jet classification area.In this thesis,a bidirectional coupled particle tracking model is adopted to investigate the flow of the sepiolite powder around the coanda block in the Jet classification area.To analyze the different size sepiolite particles flow in the jet classification area to find out the best technological parameters under the condition of different parameters,respectively from the particle trajectory and particle kinetic energy,X direction particle location etc.(4)Experimental study of sepiolite powder jet classification.Set up the sepiolite powder jet grading experiment platform,and carry out the two types of sepiolite powder jet classification experiments:the first is the combination of different kinds of nozzles with the different of curvature of coanda block classification experiments,find out the best combination;On the basis of the first set of experiments,the second type is to conduct a fractional experiment on the combination of the inlet velocity and the different power exhaust fan of the outlet installation to find the optimum technological parameters.Then,the experimental results are compared with the simulation analysis.The theoretical analysis and experimental results show that the classification effect of the sepiolite powder jet device is obvious,through to the different types of nozzles with the different curvature of coanda block combination optimization and control proper inlet velocity and installed power match exhauster,can effectively enhance the sepiolite superfine powder attached to the wall,improve the classification efficiency and precision of the jet grading device.