Structure Optimization And Computational Model Of Separation Performance For Tangential Solid-liquid Cyclone

In view of the fact that there is no method to solve the optimal solution of separation efficiency and pressure drop trade-off and a more accurate calculation model to predict the separation performance of solid-liquid hydrocyclone,this paper uses numerical simulation method and response surface method(RSM)to carry out multi-objective optimization design for the structure of solid-liquid hydrocyclone.Through the analysis of flow field in hydrocyclone,the influence mechanism of various factors on the separation performance of hydrocyclone is explored,and a comprehensive evaluation model is established The separation performance calculation model of hydrocyclone considering structure parameters,operation parameters and physical parameters was established.Firstly,five key structural factors were selected for single factor and screening analysis,and the overflow diameter,inlet diameter and cone angle were determined as the three most important factors affecting the separation performance of hydrocyclone.The multi-objective optimization was carried out through the central composite design(CCD)of response surface method(RSM),and the second-order response surface model of each response was successfully established,which can minimize the pressure drop and improve the separation efficiency The specific rules are as follows: the underflow rate and particle size increase,the separation efficiency increases,the pressure drop remains unchanged,the feed speed increases,the separation efficiency and pressure drop increase,the feed concentration increases,the separation efficiency decreases,the pressure drop remains unchanged,and the viscosity increases The pressure drop and pressure drop are reduced.Secondly,the internal flow field of the solid-liquid hydrocyclone optimization model and the co MParison model are analyzed,and the influence of structure,operation and physical parameters on the velocity,concentration and pressure distribution in the solid-liquid hydrocyclone optimization model is explored.The results show that the decrease of tangential velocity of the optimization model is concentrated in the peak velocity position,which reduces the pressure drop of the hydrocyclone;the axial velocity changes mainly near the peak value of the downflow,the downflow in the cone section is more orderly,the overall "inner vortex" increases,and the separation time of particles increases;the pressure drop in the outer wall area is significantly reduced,the static pressure difference is reduced,and the probability of particles entering the outer vortex from the inner vortex is reduced.Among the parameters,the inlet diameter,feed velocity and viscosity have great influence on the overall flow field,while the overflow diameter,cone angle,underflow rate and particle size are mainly in the local area,while the feed concentration has little influence on the overall flow field.Finally,according to the flow characteristics inside the hydrocyclone and the basic laws of fluid mechanics,the main dimensionless criteria affecting the separation performance are derived.Through dimensionless analysis of the separation performance data of the hydrocyclone,the mathematical calculation model of separation efficiency and pressure drop considering the structural parameters,operating parameters and physical parameters is established.Through data co MParison,the accuracy of the mathematical model is better It can meet the needs of engineering design.