Numerical Simulation Of The Gas–liquid–solid Flow In Hydrocyclones

Hydrocyclone has been widely used in various fields as important centrifuge equipments. Most of studies adopted field tests and empirical formula. However, the experiment of hydrocyclone experiences the shortcomings such as high investments, inflexible equipment movement, and long development cycle of new structures, and so on. Furthermore, the empirical formula and field experiments have been unable to satisfy the needs of hydrocyclone development. There is an urgent requirement to use computational fluid dynamics (CFD) to complete the simulation of cyclone flow field to determinine the optimal design of hydrocyclone and to reduce the design time and increase the design efficiency. In this paper, the multphase flow model is used to simulate the distribution of solid particles and liquid flow field in hydrocyclones.Multiphase Flow models such as mixture model and Euler-Euler model are applied in the simulation of hydrocyclones. The numerical results are compared with the experimental values. It is found that the mixture model is more accurate and effective than the Euler-Euler model in our simulation cases. The internal field of static pressure, the velocity and the distribution of solid particles in the hydrocyclone are obtained. The effects of material and structural parameters on the separation of hydrocyclone are studied. Numerical results show that the liquidity of flow is reduced, the production capacity and split are enhanced and the separation efficiency is reduced with the increase of the particle viscosity. As the increase of wall thickness of overflow pipe, the separation efficiency is increased and the energy consumption is reduced. The turbulence of the axisymmetric hydrocyclone entrance is weaked than the one-way hydrocyclone entrance, which make the separation more efficient and could reduce energy consumption. Finally, air column phenomenon and its formation of hydrocyclone is studied by applying VOF model. It is found that the total air column is controlled by both the overflow port and the underflow opening. Air column affects the uniformity and the stability of centrifugal field in the cyclone chamber and has adverse effects on the flow field.