SGER: Optimal Solution of the Direct and Inverse Problems of Contaminant Dispersion

ABSTRACTPROPOSAL没有。当前位置主要研究人员：DIETMAR rempfer机构：伊利诺伊理工学院污染物扩散正逆问题的最佳解决方案该项目的总体目标是开发实用的方法来预测污染物在大气中的扩散扩散，并在检测到污染物后定位其来源。如果能得到大气速度场随时间和空间的函数的完整描述，这个问题就能得到满意的解决。然而，大气流动几乎总是湍流的，这意味着在流动中存在大范围的长度和时间尺度。因此，如果想要测量这些速度场，只需简单地将传感器放置在一些规则的网格上，这些网格足够精细，可以解决重要的流动长度和时间尺度，就会发现需要大量的传感器。从这些考虑可以得出，有必要获得湍流流场的描述，该描述需要(a)最少的信息量，并且(b)在跟踪污染物浓度随时间的变化时，无论向后还是向前，都要尽可能精确。固有正交分解法（Lumley, 1971）作为一种使用最少信息量描述湍流流场的方法而发展起来。与此方法相关的技术似乎也非常适合实现上述第二个目标。在环境管理和政策领域以及在防御潜在的生物和（或）化学威胁领域，以有限的资源准确评估和预测污染物的扩散是很重要的。在2001年9月世界贸易中心遭受恐怖袭击后，国民对潜在恐怖威胁的认识发生了重大变化。在主要的关切领域中，特别是在9 / 11事件之后发生了几起涉及生物战剂（炭疽孢子）的事件之后，是使用化学或生物剂的恐怖袭击的威胁。为了防御这种攻击，重要的是要有能力及时发现这种攻击的发生，并尽可能准确地定位攻击的来源。我们项目的主要动机是开发技术和技术，使实现这些目标成为可能。

ABSTRACTPROPOSAL NO.: CTS-0350414PRINCIPAL INVESTIGATORS: DIETMAR REMPFERINSTITUTION: ILLINOIS INSTITUTE OF TECHNOLOGY OPTIMAL SOLUTION OF THE DIRECT INVERSE PROBLEMS OF CONTAMINANT DISPERSION The general goal of this project is to develop practical methods for the prediction of the dispersive spread of contaminants in the atmosphere, and for the localization of the source of contaminants once they are detected. This problem can be solved in a satisfactory manner if a complete description of the velocity field of the atmosphere, both as a function of time and of space, is available. However, atmospheric flows are almost always turbulent, which means that large ranges of length and time scales are present in the flow. Thus, if one intends to measure these velocity fields by simply placing sensors on some regular grid that is fine enough to resolve the important length and time scales of the flow, one finds that a prohibitive number of sensors will be required. From these considerations it follows that it is necessary to obtain a description of the turbulent flow field that (a) requires a minimum amount of information, and (b) allows the highest possible accuracy in tracking, both backwards and forwards in time, the evolution of contaminant concentrations as a function of time. The method of Proper Orthogonal Decomposition (Lumley, 1971) has been developed as a means to describe turbulent flow fields using a minimal amount of information. The techniques associated with this method appear to be well suited also to achieve the second of the goals mentioned above. The accurate assessment and prediction of the dispersion of contaminants with a limited amount of resources is important both in the areas of environmental management and policy, as well as in the area of national defense against potential biological and/or chemical threats. After the terrorist attacks on the World Trade Center in September 2001, the national awareness of potential terrorist threats has undergone a significant change. Among prime areas of concern, in particular after the occurrence of several incidents involving agents of biological warfare (Anthrax spores) in the wake of the September 11 events, is the threat of terrorist attacks using chemical or biological agents. In order to defend against such attacks, it is important to have the capability to detect the occurrence of such an attack in a timely manner, and to locate the source of the attack as accurately as possible. A prime motivation of our project is the development of technologies and techniques that make it possible to achieve these goals.