头部流线型回转体倾斜入水砰击流场和运动特性试验研究

Experimental Study on Fluid Filed and Motion Characteristics of Inclined Water Entry of a Revolving Body with Streamline Head

针对流线型回转体倾斜入水问题开展了试验研究,选取了3种回转体的入水角度,分别为45°,60°,75°,根据试验结果对入水空泡、喷溅皇冠的形态以及回转体的运动特性和受力情况进行了分析.试验结果表明,回转体入水角度增大会对喷溅皇冠的抑制作用减弱,使喷溅皇冠的体积增大,同时使得入水空泡在迎水侧和背水侧壁面的不对称性减弱.入水角度越大时回转体尾部空泡的形成时刻越晚,当入水角度足够小时头部与尾部的附着空泡会分别脱落.回转体入水角度越大,在水中运动时所受的合力越小,加速度也越小.相较于头部为流线型时,回转体头部为平面时会发生更剧烈的流动分离.

Experiment was carried out to research the water entry process of revolving bodies.Three kinds of water entry angles were selected,which are 45°,60°and 75°respectively.According to the experimental results,the shape of water entry cavity,splash crown,the kinetic characteristics and force situation of the revolving body were analyzed.The experimental result shows that the increase of the revolving body s water entry angle can increase the splash crown s volume.At the same time,it can weaken the asymmetry of the cavity s walls.The larger the angle of entring the water is,the later the cavity at the tail of the revolving body forms.When the water entry angle is sufficiently small,the cavities at the revolving body s head and tail fall off respectively.The larger the angle of entering the water is,the smaller the resultant force acting on the revolving body is,then the smaller the acceleration is.Compared with the revolving body with streamline head,the revolving body with flat head makes flow separation more intense.