Great Race Eddies and Turbulence

科里夫雷干湾位于苏格兰西部的朱拉岛和斯卡巴岛之间，以其汹涌的潮汐和漩涡而闻名。不太为人所知的是“伟大的种族”，这是这股水流向西延伸的壮观而狭窄的延伸。在每个潮汐周期，水被注入到洛恩湾的开阔水域，其速度与亚马逊河的排放量相当。毫不奇怪，这种流动对接收它的地区产生了深远的影响。模拟表明，在每个潮汐周期中，Race的头部都会形成一对涡旋，北面是顺时针方向的涡流，南面是逆时针方向的涡流。这些漩涡持续了几个潮汐周期，随着它们的演变，相互作用，并被新形成的漩涡所取代，因此，伟大的种族实际上是罗恩湾的一根搅动棒。我们计划利用这个非凡的自然实验室，在理解高潮汐环境中的涡流、湍流和混合方面取得进展，这将直接促进提高对此类环境进行数值模拟的能力。该项目将使用一系列尖端技术和仪器。我们将释放一群追踪水流的表面漂浮者进入大赛跑及其漩涡，开发通过移动电话网络快速监控他们的技术。自主水下机器人(AUV)将把自己推进到大赛的下方，在最小的尺度上测量它的湍流结构，而基于船舶的勘测将从上面描绘出更广泛的图景。这些技术中的每一种都将有助于我们对建筑的理解。一旦确定了大种族的本质和行为，关键任务将是了解能量是如何在不同尺度的涡流中分配的，以及这种能量如何随着距离涡源的增加而在尺度之间“级联”。正是这些特征，一个成功的数值模型才能准确地表现出来。模型开发是该项目不可或缺的一部分。从实地项目中获得的知识将直接用于评估和改进模型及其对太小而无法直接表示的运动的处理。最初的重点将是大赛及其周围环境的局部规模模型。一项学生奖学金将考虑将这种规模获得的知识纳入更广泛的区域模型，可能会扩展到整个苏格兰西海岸。西海岸模式不仅在重要的小规模上熟练，而且在更大的规模上代表着它们的相互联系，这将使渔业、可再生能源开发等得到更好的知情管理。

Between the islands of Jura and Scarba in western Scotland lies the Gulf of Corryvreckan, famous for its intense tidal flow and whirlpool. Less well known is the 'Great Race', the spectacular, narrow extension of that flow to the west. On each tidal cycle, water is injected into the open water of the Firth of Lorn at a rate comparable to the discharge of the Amazon. Not surprisingly, this flow has a profound impact on the region that receives it. Simulations suggest that a pair of eddies forms at the head of the Race during each tidal cycle, a clockwise eddy to the north and an anticlockwise eddy to the south. These eddies persist for several tidal cycles as they evolve, interact and are displaced by newly-formed eddies, so the Great Race is effectively a stirring rod for the Firth of Lorn. We plan to use this remarkable natural laboratory to make advances in the understanding of eddies, turbulence and mixing in highly-tidal environments which will feed directly into an improved ability to simulate such environments numerically. This project will use an array of cutting-edge technologies and instrumentation. We will release clusters of flow-tracking surface drifters into the Great Race and its eddies, developing techniques for rapidly monitoring them via a mobile phone network. An Autonomous Underwater Vehicle (AUV) will propel itself beneath the Great Race, measuring its turbulent structure on the smallest scales, while ship-based surveys will paint out the wider picture from above. Each of these techniques will contribute to our building understanding. Once the essential nature and behaviour of the Great Race have been determined the key task will be to understand how energy is distributed among eddies of different scales and how this energy 'cascades' between scales with increasing distance from the eddy source. It is these features that a successful numerical model will represent accurately. Model development is an integral part of this project. The knowledge gained from the field program will feed directly into evaluating and improving models and their treatment of motions that are too small to be directly represented. The initial focus will be on a local-scale model of the Great Race and its surroundings. A studentship will look at incorporating knowledge gained at this scale into wider area models, potentially extending to the entire west coast of Scotland. A west coast model that is skilful at the important small scales but also represents their interconnection at larger scales will allow better-informed management of fisheries, renewable energy development and more.