Theoretical studies of eddy mixing

这项研究的总体目标是了解材料是如何通过海洋和大气中的波动运动进行运输的。该项目涉及创建一些模型，这些模型可以实时运行，可以用来直观地说明搅拌和扩散之间的区别，以及两者一起可以使示踪剂均质化的速度。这种方法有助于理解涡旋和天气系统在确定污染物、生态系统的组成、热量和臭氧的传输和分布方面的重要性。这些模型将在网上和一本关于数值流体力学的互动教科书中提供。该项目包括一名研究生的培训。该项目将使用可以精确控制扩散的理想化流动模型来研究涡旋混合过程。这项研究的具体目的是帮助更好地理解：(1)通量是否是非局部的(即，不仅取决于感兴趣点处平均值的梯度的值)，(2)平均(搅动的非局部性质发挥作用)和涡流性质中的非均质性的影响，以及(3)生物地球化学变量等反应场的通量与被动示踪剂的区别。模拟和分析方法将用来更深入地了解过程的作用和它们之间的相互作用。

The overall goal of this study is to understand how material is transported by fluctuating motions in the ocean and the atmosphere. The project involves creating a number of models which can be run in real-time and can be used to illustrate visually the distinction between stirring and diffusion and the rapidity by which both together can homogenize a tracer. The approach can help in the understanding of the importance of eddies and weather systems in determining the transports and distributions of pollutants, components of ecosystems, heat, and ozone. The models will be made available on the web as well as in an interactive textbook on numerical fluid mechanics. The project includes training of a graduate student.This project will investigate eddy mixing processes using idealized flow models for which the diffusion can be precisely controlled. The specific aims of the study are to contribute to improved understanding of: (1) the ways in which fluxes are non-local (i.e., depend on more than just the value of the gradients of the mean at the point of interest), (2) the effects of inhomogeneities both in the means (where the non-local nature of stirring comes into play) and in the eddy properties, and (3) how fluxes for reacting fields such as biogeochemical variables differ from passive tracers. Simulations together with analytical methods will be used to gain a deeper insight into the processes acting and the interplay among them.