Fundamental Study of Aerosol Charging by Ions and Free Electrons in the Transition and Free-Molecule Regimes

过渡和自由分子状态下离子和自由电子气溶胶充电的基础研究

• 批准号: 9304152
• 负责人: David Y.H. Pui
• 金额: $ 23.41万
• 依托单位: University of Minnesota-Twin Cities
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1993
• 资助国家: 美国
• 起止时间: 1993-07-01 至 1997-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9304152&HistoricalAwards=false
• 关键词: Fundamental; Study; Aerosol; Charging; Ions

9304152 Pui The proposed study deals with experimental and theoretical investigations of aerosol charging by ions and free electrons in the transition and free-molecule regimes. It is aimed to resolve existing discrepancies between theories and experiments. Aerosol charging and the subsequent manipulation of the particles in an electric field are effective means of measuring, classifying and collecting them. The project will first focus on developing an aerosol charger of low particle-loss, capable of operating under vacuum and in high purity gases. It will be followed by experimental studies of aerosol charging by ions and free electrons. Aerosol charge distributions will be measured. This method of testing charging theories is more sensitive than the traditional charged fraction measurement. A numerical solution to the Boltzmann collision equation will be obtained to compare with the existing theories and with data obtained. The results of this study should provide a better understanding of fundamental transfer processes and the needed knowledge base towards improving the collection efficiency of electrostatic precipitations in the air pollution control industry, measuring and classifying nanometer particles in the materials industry, and controlling particulate contaminants in plasma reactors in the microelectronics industry. ***

9304152 Pui 拟议的研究涉及过渡和自由分子状态下离子和自由电子对气溶胶充电的实验和理论研究。 其目的是解决理论和实验之间现有的差异。 气溶胶充电以及随后在电场中对颗粒进行操作是测量、分类和收集颗粒的有效方法。 该项目将首先专注于开发一种低颗粒损失的气溶胶充电器，能够在真空和高纯度气体中运行。 随后将进行离子和自由电子气溶胶充电的实验研究。 将测量气溶胶电荷分布。 这种测试带电理论的方法比传统的带电分数测量更灵敏。 将获得玻尔兹曼碰撞方程的数值解，以与现有理论和获得的数据进行比较。 这项研究的结果应该有助于更好地理解基本转移过程和所需的知识库，以提高空气污染控制行业中静电沉淀的收集效率，测量和分类材料行业中的纳米颗粒，以及控制微电子行业中等离子体反应器中的颗粒污染物。 ***