Effect of the central rod dimensions on the performance of cyclone separators - optimization study

Abstract

• A large (30) number of geometrical configurations of the rod were analyzed. • The application of the rod inside the cyclone significantly improved its performance. • The use of the rod in each of the variants increased the value of overall separation efficiency. • The use of the rod allowed to reduce the Eu in each of the proposed geometries. • The use of the rod stabilized the flow in the area of the inner vortex. The study explored areas related to the effect of installing an additional element in the axis of the cyclone separator (in the form of a rod with a circular cross-section) on its performance. 30 geometrical variants (the variable parameters included rod diameter and length) were used for this purpose. The research was carried out using three methods – CFD (based on LES and DPM models), experimental research and stereo-PIV. The use of three research methods made it possible to conduct the process of validating the results. The placement of a rod with a circular cross-section on the axis of the cyclone separator significantly improved its performance (overall separation efficiency, Stk 50 and Eu ). The most beneficial variant led to an increase in the overall separation efficiency by 8.2% and a reduction in Stk 50 by 25.5%. In the case of a pressure drop (expressed as Eu ), all variants generated a lower value of Eu than the base variant - the maximum reduction observed was 23.9% (as compared to the base model). Additionally, to comprehensively study the effect of using an additional element on the flow field, the mean and fluctuating velocity and pressure fields were analyzed for individual variants and compared with the standard geometry. Furthermore, it was observed that the use of a rod stabilized the flow in the region confined to the inner vortex, increased the symmetry of the flow, and improved the performance of cyclone separators.