锥头圆柱体高速入水空泡数值模拟

采用流体体积法（VOF，Volume of Fluid）多相流模型，引入动网格技术，对锥头圆柱体垂直自由高速入水问题开展了数值模拟研究，分析了航行体入水后速度及入水空泡形态的发展规律，并与文献基于能量守恒定律的理论结果进行比较，两者吻合较好.研究结果表明，高速入水初期，结构受到极高的冲击载荷，导致速度迅速衰减；随着入水深度的增加，空泡不断拉长并向径向扩张，空泡内空化现象明显，空泡内混合相对空泡壁及空泡分离点附近压力分布影响显著.对于不同速度入水的研究结果表明，入水速度越高，航行体头部压力峰值越大，相同时刻入水空泡最大直径也越大.

Numerical simulation of high-speed water-entry cavity of cone cylinder

Numerical simulation for modeling the cavity formation induced by the high-speed water-entry of a cylinder body with a cone head was performed. Volume of fluid (VOF) model and dynamic mesh were introduced for the multiphase flow and the movement of the body. The velocity attenuation and induced cavity shape were obtained with an initial velocity of 500 m/s. Good agreements were obtained compared with the theoretical results. During the early period of the water entry, the penetrating velocity decreased rapidly because of the high impact load affected on the cone which can be thousand times atmospheric pressure. The maximum cavity diameters of the water-entry cavity get larger when the initial velocity is higher. As the rigid body moves deeper, there is more vapor than air; the multiphase affects the stability of the cavity markedly.