新型离心连续分选机数值模拟

Numerical Simulation of a New Type of Centrifugal Continuous Separator

离心力场能够减小微细颗粒的沉降时间,降低传统重力分选粒度下限,提高分选效率,但目前应用的离心流化分选机均为间断式排料设备,难以连续运行。本文开发了一种新型离心流化连续分选机,采用计算流体力学(computational fluid dynamics,CFD)与离散单元法(discrete element method,DEM)双向耦合技术对连续分选过程进行研究。采用Fluent研究了分选机内流场特征,通过Fluent与EDEM耦合研究了不同密度的颗粒在离心连续分选机内的运动分离过程。结果表明:液相在连续分选机螺旋槽内能够形成较厚的流膜,并延长了液相在分选过程中的运动路径,提高了物料分层分离时间,强化了物料按密度分离。利用新型离心连续分选机,能够有效实现离心连续分选。

The centrifugal force field can reduce the sedimentation time of fine particles,reduce the lower limit of the particle size in traditional gravity sorting and improve the sorting efficiency.However,the centrifugal fluidized sorting machines currently in use are discontinuous discharge equipment,which is difficult to operate continuously.This article proposed a new type of centrifugal fluidized continuous sorting machine,using computational fluid dynamics(CFD)and discrete element method(DEM)bidirectional coupling technology to study the continuous sorting process.Fluent is used to study the characteristics of the flow field in the separator,and the movement and separation process of particles of different densities in the centrifugal continuous separator is studied through the coupling of Fluent and EDEM.The results show that the liquid phase can form a thicker film in the spiral groove of the continuous separator,extend the movement path of the liquid phase in the separation process,increase the separation time of materials,and strengthen the separation of materials by density.The use of the new centrifugal continuous separator can effectively realize continuous centrifugal separation.