A vortex ring impinging on a solid plane surface—Vortex structure and surface force
A vortex ring impinging on a solid plane surface—Vortex structure and surface force
复制标题
DOI：
10.1063/1.868527
复制
发表时间：
1995-06
影响因子：
4.6
通讯作者：
C. Chu;Chi-Tzung Wang;Chien-Cheng Chang
中科院分区：
文献类型：
--
作者：
C. Chu;Chi-Tzung Wang;Chien-Cheng Chang
对垂直撞击固体平面的涡环进行了数值模拟和实验研究。特别强调了在雷诺数为500到2000之间时的涡旋结构和相关的表面力。沿着昌[PRC.]的路线R.Soc.伦敦爵士。A 437,517(1992)]，力被认为是由流动中具有不消失的涡量的流体元素贡献的。这一观点为阐明撞击过程中产生小净表面力的详细机理提供了一个独特的机会。结果表明，较小的净表面力是由于主涡环对表面的推力和诱导边界层对表面的吸力相互抵消的结果。然而，推力和吸力都比净表面力大好几个数量级。这一事实为有关作用力的流动操纵提供了正确的方向。
A joint numerical and experimental investigation has been performed to study a vortex ring normally impinging on a solid plane surface. Specific emphasis is placed upon the vortex structure and the associated surface force at Reynolds numbers between 500 and 2000. Along the line of Chang [Proc. R. Soc. London Ser. A 437, 517 (1992)], the force was viewed to be contributed by fluid elements with nonvanishing vorticity in the flow. This viewpoint enables the paper to provide a unique opportunity to shed light on the detailed mechanism which causes a small net surface force during the impingement process. It is found that the small net surface force results from the cancellation of a force pushing on the surface, due to the primary vortex ring, and a suction force, due to the induced boundary layer. Nevertheless, both the pushing and suction forces are much larger than that of the net surface force by several orders of magnitude. This fact provides proper directions for flow manipulation regarding forces exe...