COLLABORATIVE RESEARCH: Laboratory Simulation of Lightning and Dusty Plasmas

(与EPS00-80862合作)沙漠研究所(大气科学)、内华达大学雷诺分校(物理系，高能量密度科学组)和俄克拉荷马大学气象学院的科学家将合作设计和建造一个系统，以便在实验室中模拟和研究在各种地面和地外条件下通过含有云和气溶胶粒子的大气层进行的电放电。闪电是一种放电，在雷暴及其以上的大气中、火山喷发和其他行星的云层中发生，特别是在木星上。该系统还将非常适合于研究生产和修改气雾剂(如钻石)的某些工业工艺，以及航天器、运载火箭和电力传输系统的雷击防护技术。它将具有高达100万伏的高压能力，通过一个立方米的实验室云室，放电电流高达100,000安培，气体成分、压力、温度和相对湿度受到控制，并将能够填充挥发性物质的颗粒云，如水滴和冰晶，以及低挥发性的气溶胶，如某些矿物和碱卤化物。电力系统将由马克思银行并联串联的电容器以及附加元件组成，具有控制电压、电流和电流上升和下降时间的能力。该电离室将携带适当的馈通和电极，用于直接放电，以及一个感应回路，以提供无电极的环形放电。电流上升和下降的时间常数(分别约为100纳秒和10微秒)将受到控制，以直接模拟大气和其他过程。将使用条纹相机和门控光学探测器测量放电的形式和速度。将研究不同大小、形状和组成的颗粒在微量气体成分变化中的作用，还将在选定的可见光、紫外光和X射线波长上进行发射率/吸收测量。燃烧室将设计有内部传感器和适当的传输窗口，用于外部激光诊断。该系统的实用性将在第二年通过对通过冰和水云界面的领先排放尖端以及NOx产生率的初步研究来展示，这两个问题都是大气科学中的当前科学问题。

(In collaboration with EPS 00-80862)Scientists at the Desert Research Institute (Atmospheric Sciences); University of Nevada, Reno (Department of Physics, High Energy Density Science Group), and the School of Meteorology at the University of Oklahoma will collaborate to design and construct a system to simulate and study, in the laboratory, electrical discharges through atmospheres containing cloud and aerosol particles over a wide range of terrestrial and also extraterrestrial conditions. Lightning, as an electrical discharge, occurs through the atmosphere in and above thunderstorms, in volcanic eruptions and in clouds of other planets, notably Jupiter. The system will also be well suited to study certain industrial processes for producing and modifying aerosol (such as diamond) and the technology of protection from lightning strikes to spacecraft launch vehicles and electrical transmission systems. It will have a high voltage capability, up to one million volts, with a discharge current of up to 100,000 amps through a cubic meter laboratory cloud chamber with controlled gas composition, pressure, temperature and relative humidity and will be capable of being filled with particulate clouds of both volatile materials, such as water droplets and ice crystals, as well as aerosol of low volatility, such as certain minerals and alkali halides. The electrical system will consist of a Marx bank parallel - series arrangement of capacitors together with additional elements, with capability for control of voltage, current and current rise and fall time. The chamber will carry appropriate feed-throughs and electrodes for direct discharge and an inductive loop to give an electrode-less ring discharge. The time constants of current rise and fall (on the order of 100 nanoseconds and 10 microseconds, respectively) will be controlled to give direct simulation of atmospheric and other processes. Measurements will be made of the form and speed of the discharge using a streak camera and gated optical detectors. The role of particulates of different size, shape and composition as they relate to changes in trace gas composition will be investigated and emissivity/absorption measurements in selected visible, UV and x-ray wavelengths will also be performed. The chamber will be designed with internal sensors and appropriate transmission windows for external laser diagnostics. The utility of the system will be demonstrated in the second year through initial studies of the leading discharge tip through ice and water cloud interfaces and in the rate of NOx production, both of which are current scientific issues in atmospheric science.