Experimental and Computational Study of Vortex Rings in Water Subject to Coriolis Forces induced by Background System Rotation - 1=Engineering

该计划的目标是研究受背景系统旋转影响的涡旋环动力学的基本物理。涡旋动力学影响着绝大多数涉及液体或气体的应用工程问题。涡旋环是一种几何上简单的涡旋结构，几十年来一直被用作研究与控制涡旋形成、运动、稳定性和层流-湍流过渡的物理相关的一般问题的范例。涡旋也是底层和控制流体湍流的基本流动结构。湍流被认为是经典力学中尚未解决的突出问题。与背景系统旋转相关的科里奥利力从根本上改变了流体流动，并导致许多在非旋转流动中完全未知的反直觉现象。旋转流在应用工程环境中非常普遍。背景旋转对涡旋环的影响基本上是一个完全未开发的研究领域。唯一现存的出版物之一是由项目主管P.J.托马斯教授出版的。关于这个问题的出版物很少的原因是，只有极少数的实验室有必要的基础设施来进行必要的实验。自我们之前的出版物以来，为所考虑的问题获取数据所需的相关测量技术（粒子图像测速法）已经取得了实质性的进展。因此，利用现代最先进的测量方法来解决科氏力对涡旋环动力学的影响问题是及时的。在我们之前的文章中，我们定性地发现了许多新的流动现象，但由于计算机辅助测量技术还没有发展到能够进行所需定量测量的阶段，因此当时还没有对这些现象进行详细的探索。但是，现在可以执行这些测量，并且计划进行这些测量，并将获得的数据与并发计算模拟的结果进行比较。

The goal of the proposed project is to investigate the fundamental physics governing the dynamics of vortex rings subject to background system rotation. The dynamics of vortices affect the vast majority of applied engineering problems involving liquids or gases. Vortex rings are a geometrically simple vortex structure that has served for decades as a paradigm to study general issues associate with physics governing the formation, the motion, the stability and the laminar-turbulent transition of vortices. Vortices are also the fundamental flow structures underlying and governing fluid turbulence. Turbulence is considered to be the outstanding unresolved problem of classical mechanics.Coriolis forces associated with background system rotation fundamentally alter fluid flows and lead to many counterintuitive phenomena entirely unknown in non-rotating flows. Rotating flows are prevalent in applied engineering contexts. The effects of background rotation on vortex rings are an essentially entirely unexplored research area. One of the only existing publications is by the project supervisor Prof. P.J. Thomas. The reason why publications on the subject are scarce is because only a very small number of laboratories have the required infrastructure available to perform the necessary experiments. Since our previous publication, the relevant measurement techniques (Particle Image Velocimetry ) required to obtain data for the problem considered have substantially advanced. It is therefore timely to readdress the issue of the effects of Coriolis forces on the dynamics of vortex rings by means of modern state-of-the-art measurement methodologies. In our previous publication many new flow phenomena were identified qualitatively but, at the time, had to remain unexplored in detail since the computer-aided measurement technology had not advanced to a stage that enabled the required quantitative measurements. However, these measurements can now be performed and it is planned to conduct these and compare the data to be obtained to results of concurrent computational simulations.