Turbulent transport within plant canopies

湍流弥散量的精确测量和预测 例如热量、二氧化碳和地球表面附近的颗粒物， 从陆地能源和碳收支的研究 有效的空气污染控制，反恐工作。理论描述 的湍流色散的欧拉或拉格朗日框架。 现场测量几乎普遍在欧拉框架中， 的实际必要性，因此，使用欧拉描述的文献是最 普遍存在。然而，拉格朗日框架在许多方面更理论化， 令人满意的和强大的，和一些显着的进展，拉格朗日 理论和应用已经在过去的二十年左右。拉格朗日 该理论是基于对许多扩散粒子路径的统计分析， 是一个“粒子跟随”的框架，因此基于全导数。的 拉格朗日方法的力量来自这个框架，但它也需要 在同一个框架内的湍流统计知识。总体重点 这项研究计划的一个重要部分是提高我们确定拉格朗日量的能力， 统计学和应用知识的实际分散问题。

Accurate measurements and predictions of turbulent dispersion of quantities such as heat, CO2 and particulates near the earth's surface are essential for a number of applications ranging from studies of the terrestrial energy and carbon budgets to effective air pollution control to anti-terrorism efforts. Theoretical descriptions of turbulent dispersion are posed in either Eulerian or Lagrangian frameworks. Field measurements are almost universally in the Eulerian framework out of practical necessity, and thus the literature using Eulerian descriptions is most prevalent. However, the Lagrangian framework is in many ways more theoretically satisfying and powerful, and a number of significant advances in Lagrangian theory and application have been made over the last two decades or so. Lagrangian theory is based on the statistical analysis of the paths ofmany diffusing particles; it is a 'particle-following' framework and therefore based on the total derivative. The power of the Lagrangian approach comes from this framework, however it also requires knowledge of turbulence statistics in the same framework. The overall focus of this research program is on improving our ability to determine the Lagrangian statistics and applying that knowledge to practical dispersion problems.