水下航行体通气空泡溃灭特性研究

通过水洞实验对水下通气航行体通气空泡进行实验研究，分析航行体通气空泡通气停止后空泡行为。为了研究通气空泡溃灭过程的脉动特性，通过高速摄像和动态测力系统测量航行体表面空泡演变过程和压力变化情况。实验结果表明：脱落空泡运动过程中，其形状变化可分为空泡凹陷、空泡断裂、空泡脱落和溃灭4个阶段。脱落空泡在近模型壁面发生溃灭时，通过表面压力传感器捕捉到空泡的溃灭压力。对空泡溃灭压力实验结果与基于空泡生长和溃灭理论的计算结果进行了对比，理论结果与实验结果具有较好的一致性。

Research on Collapse Characteristics of Ventilated Cavities around an Underwater Vehicle

The collapse characteristics of ventilated cavities around an underwater vehicle are studied through water tunnel experiment, and a behavior of a ventilated cavity stopping subsequent cavity from generating is analiyzed. In order to analyze the oscillation characteristics of cavities during collapse, the high-speed camera and dynamic force-measuring systems are used to record the evolution process of ventilated cavities and the change in pressure on underwater vehicle. The experimental results show that the changing process of shed cavity can be classified into four periods: generation, cavity breakage, cavity shedding, and collapse. Cavity collapse depends on the state of flow field. The cavity collapses when the flow is in turbulent state. The cavity collapse at a fixed point can be captured by the pressure sensors. As a shed cavity moves near mode boundary, the cavity collapses. The shed cavity and pressure are investigated experimentally, and the experimental results of collapse pressure are compared with the calculated results based on Rayleigh-Plesset equation. The experimental value of collapse are in good agreement with the theoretical value.