The impact of water storage volume on the self-priming performance of a prototype self-priming pump

The original water storage volume inside self-priming pump is crucial to rapidly finish the self-priming process. However, the quantitative relationship between water storage volume and self-priming performance has not been fully clarified. This paper establishes a circulating piping system that includes pump, tank, and valve, etc. by means of CFD technology. Additionally, the speed-up phase during starting period is also incorporated into the calculations through user-defined functions. Based on the Volume of Fluid (VOF) multiphase flow model, numerical studies were conducted to examine the impact of three different initial water storage volumes on the self-priming performance of the pump. The initial water storage volume primarily affects the accelerated exhaust phase; when the initial storage volume is smaller, the self-priming rate inside the pump is actually higher, reducing the self-priming completion time by 0.6 seconds compared to larger storage volumes. The water storage volume within the pump has a minimal effect on the time required for the flow rate to reach a steady value, with stable flow rates ranging from 119.28 to 120.78 m³/h across all schemes, though larger storage volumes may induce backflow at the pump outlet. When the storage volume is larger, it takes longer for the head to reach a stable value.