【摘要】 为研究小型运动体高速倾斜入水时的空泡流动特性,采用求解雷诺时均Navier-Stokes方程的方法开展数值模拟。应用实验结果验证了数值方法的正确性。基于该方法对入水过程流体动力特性、流场结构特性与空泡发展进行分析,并研究了入水角度对入水流场的影响。研究结果表明:运动体在入水撞击阶段受到较大的阻力、升力和力矩,同时承受着极强的载荷;随着入水的深入,头部半球形高压区逐渐向头部中点移动,且空泡壁面的速度方向由指向水中向指向空泡内过渡;入水角度越小,撞击阶段阻力系数与砰击压力越小,入水后越容易发生弹道偏移,同时拉脱现象发生得越晚,入水空泡的最大尺寸越大。更多还原

【Abstract】 The characteristics of cavity flow around a small moving body under the high-speed oblique water-entry are analyzed,and the Reynolds-averaged Navier-Stokes equations are solved for simulation. The computational method is validated by comparing the simulated results with the experimental results. The characteristics of multiphase flow during water-entry and the influence of entry angle on water-entry flow field are investigated based on the computational method. The results show that the moving body is subjected to large drag,lift,moment and impact in the impact phase; the hemisphere-like high pressure area moves from the lower part of nose tip to the center of nose tip as the moving body continues to penetrate;the direction of velocity of cavity wall points to water first and then the cavity; the small entry angle causes small drag coefficient and impact in the impact phase and trajectory deflection; and the cavity is subsequently pulled away and the maximum size of the cavity is large when the moving body enters the water at a small entry angle.更多还原