Numerical Simulation Of Liquid-solid Two-phase Flow In A Cylindrical Hydrocyclone

Although there have been deep study of inter flow field in hydrocyclone in recent years, the study in column hydrocyclone is very limited. Column hydrocyclone is more and more widely used in mineral processing. This is mainly due to its no conical body, less abrasion, lower pressure decrease and higher volume throughput. A circle flow exists in the bottom of this type hydrocyclone. Solid particles get together in there and form a circumfluence flow bed. This character is useful for particle classification and two phases separation which have same particle size distribution but different density.A multiphase flow model is established in column hydrocyclone using mixture multiphase model and Reynolds stress model in this paper. Three-dimensional numerical simulation of liquid-solid two phases flow field and separating process which solid phase volume is more than 10 percent using above multiphase flow model has been done. The pressure distribution, tangential velocity, axial velocity, radial velocity and volume fraction of two phase in various period of time are given, and that the performance of separation is predicted. From the analysis and comparing with different illustration, it proves that the numerical model used in this paper is correct and the results of numerical study are in agreement with the facticity about the flow field.Base on numerical simulation, the theoretical analysis of flow field for this type hydrocyclone is studied. The results show that the second phase doesn't change the whole flow field distribution law. The radial velocity difference of two phases is the basic premise for their separation. It is found that there is obvious separation efficiency on the inlet body , the column body has separation function too, the bottom body is a centrifugal sedimentation area with bad separation. There is an inner boundary within the rotational flow field of hydrocyclone. The velocity head is zero on the inner boundary. As liquid flows collide with each other around the liquid inlet, a chaos flow is formed along the liquid overflow duct wall. This chaos flow is also called as short-out flow. Along the geometry axe of hydrocyclone, source and converge alternately form in...