Interactive effects between feed flow rate and feed size distribution (FSD) are numerically investigated. The results show that, for too large or too small feed flow rate, when the FSD increases, the content of solid particles misplaced to the overflow or underflow increases, leading to a decrease in separation sharpness. These results can be explained by the multiphase flow pattern and solid partide spatial distribution. What's more, when the feed flow rate too small, the differences between the equilibrium radiuses of different sized partides are small, resulting in low separation sharpness. When the feed flow rate is too large, the regular distribution of different sized particles in the radial direction is severely destroyed. Based on the results from this study, in order to achieve the desired separation performance and the precise particle separation, it is recommended to adapt to changes in the FSD by appropriately increasing the feed flow rate. (C) 2020 Elsevier B.V. All rights reserved.