Three Dimensional Numerical Simulations of Tornadoes

龙卷风的三维数值模拟

• 批准号: 9521759
• 负责人: Brian Fiedler
• 金额: $ 15.23万
• 依托单位: University of Oklahoma Norman Campus
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1996
• 资助国家: 美国
• 起止时间: 1996-02-01 至 1998-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9521759&HistoricalAwards=false
• 关键词: Three; Dimensional; Numerical; Simulations; Tornadoes

9521759 Fiedler Tornadoes are recognized as one of the most violent, localized weather phenomena. Much progress has been made over the last several years in understanding both the structure of tornadic thunderstorms and the dynamics of tornado vortices. There still, however, are unanswered questions as to the dynamics of substructures contained within a tornadic vortex and the relationship between the tornado s characteristics and the local environment. In this research, tornadoes will be simulated using a very advanced three-dimensional numerical model. The model to be used is capable of continuous dynamic grid adaptation and is ideally suited for resolving moving entities requiring enhanced resolution in a relatively small region of the modeled domain. The project goal is to determine how the maximum wind speed in a tornado is related to environmental conditions, such as convective available potential energy and radial inflow at the base of the tornado. The planned numerical simulations also will allow a study of asymmetric vortex breakdown, instabilities, turbulent transport and multiple vortices. The results of this research should lead to a better understanding of the especially violent substructures of tornadoes (e.g. satellite vortices) and eventually enhance the ability to predict such phenomena. ***

小行星9521759 龙卷风被认为是最猛烈的局部天气现象之一。 在过去的几年里，人们在了解龙卷风雷暴的结构和龙卷风涡旋的动力学方面取得了很大的进展。 然而，仍然有一些未解的问题，如龙卷风涡旋内部子结构的动力学以及龙卷风特征与当地环境之间的关系。 在这项研究中，龙卷风将使用一个非常先进的三维数值模型进行模拟。 所使用的模型能够进行连续的动态网格适应，并且非常适合于解决移动实体， 在建模域的相对小的区域中的增强的分辨率。 该项目的目标是确定龙卷风中的最大风速与环境条件的关系，例如龙卷风底部的对流可用势能和径向流入。 计划进行的数值模拟还将研究不对称涡流破裂、不稳定性、湍流输送和多重涡流。 这项研究的结果将有助于更好地了解龙卷风特别猛烈的子结构（例如卫星涡旋），并最终提高预测这种现象的能力。 ***