标题： 对降水粒子电晕发射的模型研究 显示英文标题

标题： A model study of corona emission from hydrometeors

摘要： 雷云中测量到的最大电场强度比空气电击穿所需的电场强度小一个数量级。 这些低电场中闪电起始的一种解释是，由于雨滴的形状，环境电场在雨滴表面局部增强，首先在这些表面发生电击穿。 实验室实验 [Crabb & Latham, 1974] 表明，合并并形成细长水丝的雨滴可以在接近雷云中测量到的电场中产生正电晕。 我们计算了模拟合并雨滴对周围的电场分布，并使用数值模型详细研究了正电晕机制。 我们的结果与实验室观察结果一致。 在观察到闪电起始的高度（因此是低压）下，我们的结果表明，正电晕可以在观测到的云内电场下发生。 显示英文摘要

摘要： The maximum measured electric fields in thunderclouds are an order of magnitude less than the fields required for electric breakdown of the air. One explanation for lightning initiation in these low fields is that electric breakdown first occurs at the surfaces of raindrops where the ambient field is enhanced very locally due to the drop geometry. Laboratory experiments [Crabb & Latham, 1974] indicate that colliding raindrops which coalesce to form elongated water filaments can produce positive corona in ambient fields close to those measured in thunderclouds. We calculate the E-field distribution around a simulated coalesced drop pair and use a numerical model to study the positive corona mechanisms in detail. Our results give good agreement with the laboratory observations. At the altitudes (and thus low pressures) at which lightning initiation is observed, our results show that positive corona can occur at observed in-cloud E-fields.