Because of the clearance and pressure difference between the pressure side (PS) and the suction side (SS), the tip leakage flow developed and evolved into tip leakage vortex (TLV). The relationship between the swirling strength of TLV and the pressure difference between the PS and the SS was analyzed. The velocity distribution in the tip clearance was also investigated in a multiphase pump. The reliability of numerical method was verified using high-speed photography. The trajectory of TLV was found to be distributed in a wavy shape and the swirling strength of TLV was positively correlated with the pressure difference between the PS and the SS. The tip separated vortex was formed when the tip leakage flow entered the tip clearance, and the TLV was formed when tip leakage flow moved out of the tip clearance. The low-pressure region in the tip clearance consisted of two parts. The part near the PS was caused by the tip separated vortex, and the other part near the SS was caused by the TLV. In addition, the flow separation phenomenon occurred at the radial coefficient of 0.97 and led to the increase of the turbulent energy loss of the pump.

中文翻译：

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非设计条件下多相泵的尖端泄漏涡轨迹和动力学

由于压力侧（PS）和吸力侧（SS）之间的间隙和压力差，叶尖泄漏流发展并演变为叶尖泄漏涡（TLV）。分析了TLV的旋流强度与PS和SS压差之间的关系。还在多相泵中研究了尖端间隙中的速度分布。通过高速摄影验证了数值方法的可靠性。发现TLV的轨迹呈波浪状分布，TLV的旋流强度与PS和SS之间的压力差呈正相关。叶尖泄漏流进入叶尖间隙时形成叶尖分离涡，叶尖泄漏流移出叶尖间隙时形成TLV。叶尖间隙中的低压区由两部分组成。靠近 PS 的部分是由尖端分离涡流引起的，而靠近 SS 的另一部分是由 TLV 引起的。此外，在径向系数为0.97时出现流动分离现象，导致泵的湍流能量损失增加。