并列超空泡射弹弹道特性研究

Study on Ballistic Characteristics of the Parallel Supercavitating Projectiles

为了研究不同间距并列射弹对射弹的流体动力特性和弹道特性的影响,文中基于流体体积函数(VOF)多相流模型,采用多重参考系和动网格及移动计算域技术,建立射弹入水仿真模型,对单射弹和并列射弹的入水自由减速过程进行数值仿真。结果表明:并列发射工况下,射弹受到侧向力,有攻角航行时空泡形态发生明显偏移,射弹更容易穿刺空泡,并且并列间距越小,穿刺距离越长;并列射弹的阻力系数明显高于单发射弹,当并列间距为75mm时,阻力系数增加34.92%;并列射弹的运动稳定性受到并列间距的影响,在并列间距为50 mm弹径工况中,并列射弹发生颠覆,弹道失稳;随着并列间距的增大该影响逐渐减弱,当并列间距为100 mm弹径时,并列射弹弹道稳定。研究结果可为并列超空泡射弹的工程应用提供参考。

To investigate the effects of the spacing of parallel projectiles on the hydrodynamic properties and ballistic characteristics of the projectiles, a water-entry simulation model of projectiles is established on the bases of the volume of fluid(VOF) multiphase flow model, the multi-reference system, the dynamic grid and the mobile computing domain technology. The water-entry free-deceleration processes of single projectile and parallel projectiles are simulated for different spacing of the projectiles, respectively. The results show that: 1) in parallel launching condition, the projectile is subjected to lateral force, when there is an angle of attack, the cavity has obvious offset and is easier to be punctured by the projectile, and the smaller the parallel spacing, the longer the puncturing distance;2) the drag coefficient of the parallel projectiles is significantly higher than that of the single projectile, and when the parallel spacing is 75 mm, the drag coefficient increases by 34.92%;and 3) the stability of the parallel projectiles is affected by the parallel spacing, and in the case that the parallel spacing is 50 mm, the parallel projectiles overturn with instable trajectories, but this effect gradually weakens as the parallel spacing increases, and the trajectories of the parallel projectiles become stable when the parallel spacing is 100 mm. This research may provide reference for engineering application of parallel supercavitating projectiles.