Computational Investigation of Cavitation Inception in Centrifugal Pumps

This study examines the effects of suction chamber baffle configurations on both hydraulic efficiency and cavitation characteristics in a low specific speed centrifugal pump. Four baffle configurations (zero, one, two, and three baffles) were tested at three different heights using refined computational fluid dynamics simulations. The Zwart-Gerber-Belamri cavitation model was enhanced by adjusting nucleation site radius and evaporation coefficient values to better align with previous research findings. Results revealed that the optimal baffle height is approximately one-third of the impeller suction eye radius, significantly improving cavitation resistance. Under non-cavitation conditions, all baffled configurations outperformed the no-baffle setup, with a single baffle showing the best performance at twice the optimal height. Under cavitation conditions, the single baffle at optimal height achieved the highest head, while the three-baffle configuration at triple of the optimal height produced the poorest performance. This research demonstrates that implementing a single strategically positioned baffle can significantly enhance pump efficiency and mitigate cavitation risks in low specific speed centrifugal pumps.