Study On The Method And Application Of Tobacco Leaf Wind Separation Based On Gas-solid Two-phase

As one of the indispensable processes in the threshing and redrying process,the wind separation of tobacco leaves has an important influence on the subsequent processes and the sensory quality of the final cigarette.Therefore,the analysis and study of the complex multiphase flow field existing in the typical leaf and stem separation process of tobacco leaf air separation reveals the movement state of the tobacco leaf during the air separation process,which can effectively improve the efficiency of tobacco leaf air separation,thereby satisfying cigarette production The specialization and refinement of the process are also of great significance for improving the separation process of leaves and stems.Aiming at the problems of relying on experience and human trials in the process of tobacco leaf air separation process,this project has carried out a visual study on the complicated leaf and stem separation process inside the air separator,and combined the experimental data to analyze the factors that affect the effect of air separation.Analyze and optimize the process parameters in the air separation process,thus forming a scientific theory and basis to guide production.Based on the gas-solid two-phase coupling method,the gas-solid two phases are numerically simulated in Fluent and EDEM simulation software respectively through coupling simulation,and then the UDF coupling interface is used to realize the interaction between the two software environments,in order to get more Close to the actual wind split flow field and the motion state of tobacco particles in the flow field.This paper firstly describes the development status of tobacco wind distribution at home and abroad,and then establishes the movement model of the tobacco particles inside the wind divider.Through experiments,the physical parameters such as the moisture content,density and Young's modulus of the tobacco leaf are determined,and they are established in the Fluent simulation software.For the flow field environment inside the wind divider,three-dimensional models of blades,leaf stems and tobacco stem particles are established in the EDEM simulation software,and the mechanical properties of the tobacco leaf particles are set.The coupling simulation of Fluent and EDEM is used to simulate the leaves and the inside of the wind divider.The process of stalk separation is numerically simulated close to the actual working conditions.Analyzed the movement state of tobacco particles in the air separator;the influence of wind separation wind speed on the efficiency of wind separation;the influence of tobacco moisture content on the efficiency of wind separation;the influence of the feeding angle of tobacco leaves on the wind separation efficiency;the influence of the feeding speed of tobacco leaves on the wind efficiency The impact of sub-efficiency.Through research,the best working condition parameters are obtained,the wind speed of wind separation is 3.5m/s,the moisture content of tobacco leaves is about 20%,the feeding speed of leaves and stems is 2.5m/s,and the feeding angle of leaves and stems is 40°.Finally,a comparative verification experiment under the best operating parameters was carried out on the air separation process of tobacco leaves.The results showed that the average amount of leaves separated by air separation increased from 49.5% to51.25%,and the average air separation efficiency increased from 84.08% to 51.25%.88.75%,the amount of leaf stems separated by winnowing was reduced from 40% to38%,while the amount of tobacco stems did not change much,which effectively improved the wind separation effect of leaves and stems.The experimental results are basically consistent with the simulation results,and the optimized process parameters meet the requirements of process indicators;SPSS statistical software is used to analyze the correlation between the experimental results and the simulation results,and it is found that the two have a good correlation.Among them,the correlation between winnowing wind speed and wind separation efficiency is the strongest.This paper proposes a regression model for the optimization of tobacco air separation process parameters,which provides a production basis for the optimization of the process parameters of threshing and redrying in the future.