Numerical analysis of flow resistance reduction methods in cyclone separator

Abstract

Abstract In this study, numerical simulations were carried out to examine the performance of the cyclone separator with different fin diameter ratios (FDRs) and porosities on the fins. As three key indicators, removal efficiency, pressure drop and dimensionless factor (Eu) were investigated and then corresponding mechanisms of flow and separation were analyzed by discussing velocity, turbulent kinetic energy and pressure distribution. The results showed that separation and flow performances of separators kept stable for FDR less than (or equal to) 7/10. On the other hand, with the increase of the porosity, the separation efficiency and pressure drop suffered drastic losses. Compared with FDR = 1, the removal efficiency of FDR = 2/5 decreased by 6.7 percentage points (Eu was reduced by 23.5%). In addition, the removal efficiency of porosity = 0.2 was 9.2 percentage points less than that of porosity = 0 (Eu was reduced by 22.2%). Therefore, cyclone separator with FDR = 2/5 or porosity = 0.2 was recommended for low flow resistance requirements. Flow field analysis found that the weakening of the flow of the spiral fins leads to the attenuation of the tangential velocity values in the flow field downstream of the fins. Furthermore, the change of the local velocity distribution in the flow field, such as the increase of the tangential velocity, is beneficial to the increase of the demisting efficiency of the spiral mist eliminator. At the same time, it also leads to greater flow resistance.