Analysis of particle motion and wear characteristics for mixed particle sizes in centrifugal pumps

In this study, we investigated the effect of particle size distribution (PSD) variations on the particle motion characteristics and wear in centrifugal pumps. We used computational fluid dynamics (CFD) and the discrete element method (DEM) to conduct simulations for one single particle size and five mixed particle sizes. The variation of the PSD had a significant effect on the wear rate of the impeller pressure surface and the volute surface. When the proportion of small particles near the impeller increased, the wear rate decreased. Specifically, at the middle of the impeller, the wear rate changed the most significantly. For volute surfaces 6–7 and 7–8 and the diffusion section, the velocity vectors of the near-wall volute surface showed a greater accumulation of small particles, and the buffering effect on the impact of large particles increased. Thus, the addition of small particles caused the wear rate of the volute surface to decrease.