The Research On Structure Optimization Of Double Cone Water Sediment Separator Based On CFD

With the rapid development of society,science and technology in my country,the Yellow River water resources with high sand content are mostly used for agricultural irrigation,industrial water and drinking water for urban residents in the northwest.The Turbid Water Hydraulic Power Separation Device is a new type of muddy water separation device designed by Xinjiang Agricultural University.However,through related research,it is found that water and sand separation mainly occurs in the lower cone section of the device,while the cylindrical section of the device only stabilizes the flow of the upper water flow.The effect is not obvious for the separation of water and sand,and it will also cause waste of funds and inconvenience in operation in actual engineering applications.This paper aiming at the problems of the turbid water hydraulic separation clean water device,this paper proposes a double-cone water-sediment separator.Firstly,the computational fluid dynamics(CFD)method is used to conduct a macroscopic analysis of its separation process;secondly,it is combined with the solid-liquid two-phase flow theory(CFD-DEM)microscopic analysis of its separation process;once again the single factor method is used to study the performance of the double-cone water-sand separator;finally,the orthogonal test method is used to optimize the structure of the double-cone water-sand separator.It laid a solid foundation for the double cone water-sand separator to be more suitable for practical engineering applications such as the Yellow River water purification project and tap water pretreatment project.This article has achieved the following main results:1.Through the use of the CFD method to conduct a macro-study on the structural scheme,it is concluded that the double cone water-sand separator has better flow field stability and regularity than other structural schemes,and the separation efficiency is higher.Therefore,this paper finally chooses the double cone Type water-sand separator is the object of follow-up research.2.By using the CFD-DEM coupling method,the movement of sand particles in the double-cone water-sand separator and the characteristics of the water-sand two-phase flow on the separator are micro-studied.Through analysis,it is obtained:(1)The larger the sand particle size,the shorter the time the sand particles stay in the separator;(2)As long as the sand particle size is within the separation range of the separator,the sand particles will be affected by gravity,centrifugal force and Under the action of drag force and other forces,it can be quickly discharged from the sand discharge port to achieve separation;(3)The separator has a general separation effect on sand particles with a particle size of 0.015 mm and below,but for sand with a particle size greater than 0.025 The separation rate of the sand group of mm is as high as 98% or more.Comparing the coupling results with the CFD numerical simulation results,it is found that the flow field motion distribution laws of the two are basically the same,which verifies the accuracy of the CFD numerical simulation results and provides a reliable basis for the determination of the structure of the double-cone water-sand separator.3.The main parameters are controlled by single factor method,and the main parameters are studied numerically by CFD numerical simulation.This research has guiding significance for the structural optimization research of the double-cone watersediment separator.4.Research on the structure optimization of the double-cone water-sand separator by using the orthogonal test method.The results show that the significant degree of the influence of various factors on the water-sediment separation efficiency,from high to low,are: the diameter of the discharge pipe,the cone of the lower cone,the height of the cylinder,the diameter of the inner cone,and the cone of the inner cone;the model after the optimization of the structural parameters,The separation efficiency has increased by 11.65%,and the stability of the flow field has also been greatly improved.The feasibility of optimization has been confirmed.