The Influence of Wear Ring Clearance on Flow Characteristics and Energy Loss in Centrifugal Pumps based on Multiphase Simulation

Abstract

The performance of centrifugal pumps directly affects agricultural productivity and waterutilize efficiency, with their hydraulic characteristics being predominantly governed by the wear ring clearance (WRC) and the conveyed medium. This study employs the simulation with discrete phase model (DPM) to research the flow characteristics in both clear water and sedimentladen water for different WRC size. An experimental system was also constructed to validate the simulation results. The study further reveals that: the increase in leakage flow caused by the enlargement at the WRC is the dominant factor leading to the decline in the hydraulic performance of the centrifugal pump, while the influence of the sedimentladen medium is relatively minor. At the WRC, the distributions of the leakage flow and its induced recirculation zone are closely to the high entropyproductionrate (EPR) regions, confirming that the leakage flow is the primary source of energy loss. In impeller, the vortexcore accumulation areas, streamline distortion zones, and highEPR regions exhibit strong spatial agreement, indicating that vortex structures are the direct cause of flow instability and energy dissipation. Globally, as dWRC increases, both the flowinstability zones and the corresponding EPR intensity rise significantly, demonstrating that wearring erosion exacerbates hydraulic losses by intensifying flow instability. These findings provide a theoretical basis for the design of wear rings in centrifugal pumps operating in highsedimentladen environments and offer important engineering value for improving the reliability of irrigation systems and promoting the development of watersaving agricultural technologies.