论文标题
在中间速度机制下球的水面表面密封行为
The water entry surface seal behavior of spheres at intermediate speed regimes
论文作者
论文摘要
这项研究的重点是地面密封方案中球的水进入。在此，表面密封发生在球体撞击与水面的影响之后，其特征是飞溅穹顶和\ emph {low-speed}（$ u <30 $ 〜m/s）和\ emph {high-speed}（$> 165 $ 〜m/s）机制的各个Sphere temmensimes的腔体间隔。针对低速和高速的捏合时间$ t_p $的既定经验缩放定律（分别为$ t_pud^{ - 1} 〜c_d^{ - 1/2} = const $和$ t_pud^{ - 1} 〜c_d^c_d^c_d^c_d^{ - 1/2} { - 1/2} { - 1/2} { - \ propto ca^propto ca^^$}特定规模的中级制度以$ t_pud^{ - 1} 〜c_d^{ - 1/2} \ propto ca^{ - 1/2} $，这意味着腔体内的压力减小会确定表面密封动力学随着速度的增加而确定表面密封动力学。我们还报告了从深密封到地面密封的过渡，在该密封中，密封期更像是深密封。还报道了腔表面的部分倾斜，涟漪和二次捏合。
This research focuses on the water entry of spheres in the surface seal regime. Herein, surface seal occurs in the wake of a sphere impact with the water surface and is characterized by splash dome over and cavity pull-away between the \emph{low-speed} ($U<30$~m/s) and \emph{high-speed} ($U>165$~m/s) regimes for various sphere diameters $D$. The established empirical scaling laws for pinch-off time $t_p$ hold well for both low and high speeds (i.e., respectively $ t_pUD^{-1}~C_d^{-1/2}=const$ and $ t_pUD^{-1}~C_d^{-1/2}\propto Ca^{-1}$) but the transition deserves refinement. The intermediate regime in particular scales as $t_pUD^{-1}~C_d^{-1/2}\propto Ca^{-1/2}$, which means that the pressure reduction inside the cavity determines the surface seal dynamics as speeds increase. We also report on the transition from deep to surface seal, where the seal time is scaled more like a deep seal. The partial pull-away, ripples on the cavity surface, and the secondary pinch-off are also reported.
