预置舵角下超空泡航行体倾斜入水弹道特性研究

Research on the Trajectory Characteristics of Supercavitating Vehicle Obliquely Entering into Water at Preset Rudder Angle

为了研究预置舵角下超空泡航行体倾斜入水弹道特性,开展了入水角为20°时的试验研究。超空泡航行体由空气炮加速获得入水初速度,采用高速摄像机记录入水空泡流型,同时由内测系统记录航行体的运动参数和尾部压力变化。对预置舵角为0°和20°时的试验结果进行对比分析,给出了预置舵角下航行体倾斜入水弹道特性,并进一步研究了不同预置舵角对弹道的影响。试验结果表明:预置舵角为0°时航行体以超空泡状态沿直线运动;预置舵角为20°时出现显著的尾拍现象,轴向力和法向力增大,弹道特征体现为偏向水面弯曲,航行体最终以双空泡状态航行,弹道偏转趋势提升;增大预置舵角有助于增强航行体的弹道偏转能力。

A series of experiments of supercavitating vehicle at the entry angle of 20°are carried out to investigate the trajectory characteristics of supercavitating vehicle at preset rudder angle during oblique water-entry.An air cannon is set up to provide the initial velocity of supercavitating vehicle.The flow pattern in water-entry cavity is captured by using a high-speed video camera,and the variations of the motion parameters and tail pressure are recorded by using a built-in measuring system.The experimental results of supercavitating vehicle navigating at the preset rudder angles of 0°and 20°are analyzed in detail,and the water-entry trajectory characteristics of supercavitating vehicle are given.The influences of different preset rudder angles on the trajectory are further studied.The experimental results show that the vehicle moves along a straight line in a supercavitation state when the preset rudder angle is 0°;a remarkable tail-slapping phenomenon arises,and the axial force and the normal force increase when the preset rudder angle is 20°,thus causing the trajectory to bend to the surface of the water.The vehicle eventually navigates in the state of double-cavity,with enhancing the trajectory deflection.Increasing the preset rudder angle can improve the deflection ability of the vehicle.