Two counter‐rotating diffusing vortices
Two counter‐rotating diffusing vortices
复制标题
两个反向旋转的扩散涡流
DOI：
--
复制
发表时间：
1995
期刊：
影响因子：
--
通讯作者：
S. Shankar
中科院分区：
文献类型：
--
作者：
L. V. Dommelen;S. Shankar
对两个等强度反向旋转涡流的扩散问题进行了数值和分析研究。渐近展开式是针对小时间、小雷诺数和大时间的解的极限行为而推导出来的。结果用于更全面地了解涡流系统的漂移和衰减。因此，表明先前作者使用的涡流系统位置的不同测量可能会给出涡流漂移速度的显着不同的值。小雷诺数的展开表明，即使在斯托克斯极限 Re→0 下，这些差异仍然存在，其中涡度系统关于连接涡中心的线变得对称。但令人惊讶的是，大时间膨胀表明，在很长一段时间里，所有漂移速度都变得相同。此外，该万有速度与每个半平面内的平均速度不同，尽管它等于这些平面的涡度中心的速度。小型...
The problem of the diffusion of two counter‐rotating vortices of equal strength is studied numerically and analytically. Asymptotic expansions are derived for the limiting behavior of the solution for small times, for small Reynolds numbers, and for large times. The results are used to more fully understand the drift and decay of the vortex system. Thus it is shown that different measures for the position of the vortex system used by previous authors may give significantly different values for the drift velocity of the vortices. The expansion for small Reynolds number shows that these differences remain even in the Stokes limit Re→0, in which the vorticity system becomes symmetric about the line connecting the vortex centers. But surprisingly, the large time expansion shows that for large times all drift velocities become identical. Moreover, this universal velocity is different from the average velocity in each half plane although it equals the velocity of the centers of vorticity of those planes. The sm...