To investigate the influence of the stable rotational speed and discharge valve opening on the self-priming performance of a small prototype self-priming pump, this paper establishes a circulation pipeline system comprising a self-priming pump. The user-defined function (UDF) is used to realize the increase in rotational speed and its steady operating. The numerical calculations of the gas-liquid two-phase flow during self-priming process are conducted based on the volume of fluid (VOF) multiphase flow model. Meanwhile, the vortex identification methods are also employed to analyze the internal unsteady flow. The results indicate that compared to the design rotational speed, the self-priming time is shorter at off-design rotational speeds. As the discharge valve opening decreases, the self-priming time increases significantly. During self-priming process, there are significant energy losses in the areas around the impeller inlet, the outer edge of the impeller, and the tongue of the volute. • Compared to the design rotational speed, the self-priming time is shorter at off-design rotational speeds. • As the outlet valve opening decreases, the self-priming time increases significantly. • During the self-priming process, there are significant energy losses in the areas around the impeller inlet, the outer edge of the impeller, and the tongue of the volute.
Zhang et al. (Wed,) studied this question.