Numerical Investigation of Impeller Parameters and Internal Flow Characteristics in a Vortex Pump

This study employs three-dimensional unsteady CFD simulations with the sliding mesh method to investigate the influence of key impeller geometric parameters—blade partition thickness and blade inclination angle—on the internal flow and performance of a vortex pump. The results show that reducing partition thickness enhances internal flow uniformity and increases the discharge rate, while excessive thinning raises the inlet negative pressure. A rearward blade inclination of 10° optimizes flow alignment, reduces impact losses, and improves efficiency, with benefits plateauing beyond this angle. An optimized impeller design was developed, with a partition thickness of 0.8 mm, blade height of 4.6 mm, 10° rearward inclination, and 42 blades. Compared to the baseline, the optimized model increased flow rate by 14.3%, head by 2.1%, and hydraulic efficiency by 10.8%, while also promoting a more uniform flow field and stabilized vortex structure. This study provides valuable insights and a practical framework for optimizing the impeller design and internal flow management of vortex pumps.