Numerical Modeling Studies of Thunderstorm Charging and Lightning Influence on Storm Electricity in Two and Three Dimensions

二维和三维雷暴充电和雷电对风暴电影响的数值模拟研究

• 批准号: 9200698
• 负责人: John Helsdon
• 金额: $ 38.62万
• 依托单位: South Dakota School of Mines and Technology
• 依托单位国家: 美国
• 项目类别: Continuing grant
• 财政年份: 1992
• 资助国家: 美国
• 起止时间: 1992-07-01 至 1996-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9200698&HistoricalAwards=false
• 关键词: Numerical; Modeling; Studies; Thunderstorm; Charging

The objective of this research is the physics of electrification of thunderstorms, including the lightning discharge, using a numerical cloud model. The formulation of riming charge transfer will be guided by recent laboratory results showing the significance of both temperature and liquid water content. Also, the significance of ice splintering in producing lower positive charge centers will also be investigated. Improvements in the lightning parameterization scheme will include a randomization of the propagation path based on the presence of random free electrons in the vicinity of the discharge tip, the inclusion of the tip electric field in the path calculation, and a simulation of the cloud-to-ground discharge. These improvements and those mentioned above will be incorporated in the three-dimensional model. We will include a calculation of the Maxwell current into our analysis software to test the inference of Krider and Musser (1982) concerning the role of inductive and noninductive processes in driving the Maxwell current. Modeling studies of several new cases will be undertaken with both 2D and 3D models to examine electrification processes in various storms.

这项研究的目的是使用数值云模型研究雷暴带电的物理学，包括闪电放电。 边缘电荷转移的制定将以最近的实验室结果为指导，这些结果显示了温度和液态水含量的重要性。 此外，还将研究冰分裂在产生较低正电荷中心方面的重要性。 闪电参数化方案的改进将包括基于放电尖端附近存在随机自由电子的传播路径的随机化、在路径计算中包含尖端电场以及云对地放电的模拟。 这些改进以及上面提到的改进将被纳入三维模型中。 我们将把麦克斯韦电流的计算纳入我们的分析软件中，以测试 Krider 和 Musser (1982) 关于感应和非感应过程在驱动麦克斯韦电流中的作用的推论。 将使用 2D 和 3D 模型对几个新案例进行建模研究，以检查各种风暴中的电气化过程。