回转体低速串联入水空泡及运动特性试验研究

Experimental Reaserch on Cavitation and Motion Characteristics of Low-speed Water Entry of Rotary Bodies in Tandem

为研究回转体串联入水过程中的空泡演化及运动特性,基于高速摄像及时序释放系统,开展了不同入水初始间距的回转体低速串联入水试验。利用图像处理技术对采集图像序列中的回转体运动进行识别提取,得到入水初始间距对回转体的入水空泡、纵向位移及偏转角的影响规律。试验结果表明:较小入水初始间距的回转体串联入水过程中,两运动体的空泡结构及尺寸均受到影响;随着入水初始间距增大,回转体串联入水过程中依次出现碰撞扰动、封闭空腔扰动、过渡扰动与弱扰动4种运动模式,在不同的运动模式中,两运动体的空泡及运动特性存在较大差异,其中碰撞扰动模式对回转体的运动特性影响最大。

In order to study the evolutions and motion characteristics of cavitations in the process of water entry in tandem,the high-speed camera and time release system are used in testing the low-speed tandem water entry of rotary bodies at different initial spacing.The motion characteristics of rotary bodies are identified and extracted using image processing technology,and the influence of the initial spacing of water entry on cavitation evolution,longitudinal displacement and deflection angle of rotary body was obtained through test.The test results show that the cavitation structures and sizes of two rotary bodies are affected during the water entry in tandem at the small initial spacing.With the increase in the initial spacing of water entry,four motion modes,including colliding disturbance,closed cavity disturbance,transition disturbance and weak disturbance,arise in the process of tandem water entry of rotary bodies.In different motion modes,the vacuolizations and motion characteristics of two rotary bodies are quite different.The colliding disturbance mode has the greatest influence on the motion characteristics of rotary body.