How can the appropriate near-wall grid size for gas cyclone CFD simulation be estimated?

Abstract

In this paper, one of the frequently asked questions for gas cyclone CFD simulation, that “How can the proper near-wall grid size be estimated?”, has been answered. The wall y+ definition was adopted to estimate the near-wall grid sizes. The velocities and friction factors for barrel and cone were obtained by simplifying the previous cyclone pressure drop prediction model to estimate near-wall grid sizes. The representative positions for cyclone cones have been investigated to simplify the near-wall grid estimation. Moreover, new correlations for velocities inside the vortex finder have been developed. The gas cyclones were properly simulated and compared to the previous works to assess the capability of this grid size estimation method. The CFD models developed by the estimated near-wall grid sizes represented the reasonable mean flow properties. Finally, this research concludes that the proposed near-wall grid size estimation method is essential and suitable for gas cyclone CFD simulation.