Numerical Studies of Thunderstorms Electricity and Lightning--A Look at the Paradigm

雷暴电和闪电的数值研究--范式考察

• 批准号: 9613679
• 负责人: John Helsdon
• 金额: $ 42.5万
• 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: 1997
• 资助国家: 美国
• 起止时间: 1997-06-01 至 2001-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9613679&HistoricalAwards=false
• 关键词: Numerical; Studies; Thunderstorms; Electricity; Lightning

Helsdon/Abstract The objectives of this research are charge separation process in the influence of lightning on the electrical structure and development of thunderclouds, primarily using the 3D storm electrification model. With respect to charging processes we plan to examine the convective hypothesis, acting alone, to see if it is capable of producing strong electrification within storms; continue to investigate noninductive charging processes based on the most recent laboratory findings; look at the hail/cloud water inductive mechanism to determine its importance in the electrification during the mature stage of storms; and examine several mechanisms, including splashing of hail and supercooled liquid water, to investigate the production of charge structures that might favor positive cloud-to-ground lightning. We also plan to incorporate electrical effects on the vertical and horizontal motion of charged hydrometeors as well as the calculation of detailed hydrometeor charge budgets. With respect to the lightning scheme, we will develop a more randomized propagation for the simulated channel, incorporating the electric field due to the channel itself. We will continue to investigate the termination criterion, with the intent of solving the problem of channel propagation to ground. Finally, we plan to run simulations with multiple discharges to determine their influence on the charge rearrangement during the active lightning phase of storms.

Helsdon/摘要 本研究的目标是闪电对雷暴云电结构和发展影响中的电荷分离过程，主要使用三维风暴起电模型。 关于充电过程，我们计划检验单独作用的对流假设，看看它是否能够在风暴中产生强烈的电气化; 根据最新的实验室研究结果，继续研究非感应充电过程;研究冰雹/云水感应机制，以确定其在风暴成熟阶段的电气化中的重要性;并研究几种机制，包括冰雹和过冷液态水的飞溅，以研究可能有利于正云对地闪电的电荷结构的产生。 我们还计划将电效应的垂直和水平运动的带电水凝物，以及详细的水凝物电荷预算的计算。 关于闪电方案，我们将为模拟通道开发一个更随机的传播，并将由于通道本身产生的电场纳入其中。 我们将继续研究终止准则，目的是解决信道传播到地面的问题。 最后，我们计划运行模拟多次放电，以确定其对电荷重排的影响，在活跃的闪电阶段的风暴。