Analytical and Numerical Studies of Deep Overflows and Related Circulations

深度溢出及相关循环的分析和数值研究

• 批准号: 0525729
• 负责人: Lawrence Pratt
• 金额: $ 78.64万
• 依托单位: Woods Hole Oceanographic Institution
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-09-01 至 2010-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0525729&HistoricalAwards=false
• 关键词: Analytical; Numerical; Studies; Deep; Overflows

Intellectual Merit:This project seeks to extend our current understanding of deep overflows through a comprehensive study of rotating hydraulics of two-layer sill flows connected to broad basins. Two-layer dynamics are thought to be important in the overflows of a number of important passages, including the Denmark Strait, the Faroe-Bank Channel, and the Vema Channel, either in accounting for the influence of reverse flows at the surface or the evolution of distinct water masses feeding the channel and contained within the overflows. This study brings analytical and numerical techniques to bear on a number of fundamental issues including the dynamically consistent connection of two-layer hydraulic theory to the neighboring basin flows for both exchange and unidirectional flow cases, aspiration of deep layers, general methods for the identification of hydraulic control and the isolation of special features such as hydraulic jumps in channels with arbitrary cross section, and the role of time-dependence in straits and coupled basin-strait systems. The elucidation of these issues will aid in the interpretation of results from more complicated numerical models, observations, and in the planning of strategies for long-term monitoring of overflow transport from within upstream basins. Also, the investigators will continue to find ways of presenting the results so as to favor the intuition and to be accessible to the non-specialist. Broader Impacts:Deep passages offer ideal points to monitor the overturning circulation. However, this can only be done properly after development of hydraulic theories with improved realism and once the dynamical connections between strait and basin flows are understood. This work will begin to answer some of these questions and should be of wide interest beyond the specific dynamics explored here. The two investigators are both active in the MIT/WHOI Joint Program and the results of this research will quickly reach the classroom. A small percentage of the grant will support the completion of a graduate text on ocean strait and sill flow and other applications of hydraulics in geophysics. The grant will also provide continuing support for a graduate student to complete his thesis.

知识价值：这个项目试图通过对连接到宽阔盆地的两层基流的旋转水力学的全面研究，扩展我们目前对深度溢流的理解。两层动力被认为在包括丹麦海峡、法罗-班克海峡和维马海峡在内的一些重要航道的溢流中是重要的，无论是考虑到表面逆流的影响，还是考虑到为航道提供和包含在溢流中的不同水团的演变。这项研究运用解析和数值技术研究了一些基本问题，包括两层水力理论在交换和单向流动情况下与相邻盆地水流的动态一致性连接、深层吸力、水力控制的一般识别方法和任意断面渠道中的水跃等特殊特征的隔离，以及时间依赖性在海峡和盆-海峡耦合系统中的作用。阐明这些问题将有助于解释更复杂的数值模式和观测结果，并有助于规划对上游流域溢流输送进行长期监测的战略。此外，调查人员将继续寻找呈现结果的方法，以便有利于直觉，并使非专家能够理解。更广泛的影响：深通道为监测倾覆的环流提供了理想的点。然而，只有在改进了现实性的水力学理论发展之后，一旦理解了海峡和盆地水流之间的动力联系，才能正确地做到这一点。这项工作将开始回答其中的一些问题，并应引起广泛的兴趣，而不是这里探索的特定动态。这两位研究人员都活跃在麻省理工学院/世界卫生组织联合项目中，这项研究的结果将很快进入课堂。补助金的一小部分将用于完成一篇关于海洋海峡和基底流以及水力学在地球物理中的其他应用的研究生论文。这笔助学金还将继续为研究生完成论文提供支持。