Control of Plasma Instabilities

所有的等离子体都会受到各种不稳定性的影响，无论产生这些等离子体的设备类型和它们的预期应用。这些设备包括用于中性、电子束和离子束的等离子体源、任何类型的弧光放电、用于固态处理的等离子体刻蚀设备、基本实验设备、地球物理和天体物理等离子体和聚变机。不稳定性的有害后果很多：等离子体中的不均匀、运输的增加，以及宏观上的分裂(如果足够剧烈的话)。这些可以最小程度地导致设备或系统的性能降级，有时还会导致其故障。因此，消除这些不稳定总是可取的，有时也是势在必行的。本项目继续对等离子体不稳定性的主动反馈控制进行研究。具体地说，将使用一种使用小离子束的新的远程抑制器，这将对系统产生最小的扰动。此外，还将研究鲁棒控制器。将探索这些控制器在工业等离子体设备中的应用。两名教职员工和一名研究生将利用哥伦比亚大学等离子体研究实验室的设施进行拟议的研究。实验工作将利用重新设计的哥伦比亚线性机器。

All plasmas are subject to a variety of instabilities, irrespective of the type of devices in which these are produced and their intended applications. These include plasma sources for neutral, electron and ion beams, any type of arc discharge, plasma etching devices for solid state processing, basic experimental devices, geophysical and astrophysical plasma and fusion machines. The deleterious consequences of the instabilities are many: non-uniformities in plasma, increased transport and, if violent enough, a macroscopic break up. These can lead minimally to degradation of the performance of the device or system and sometimes to its break down. Therefore the elimination of these instabilities is always desirable and sometimes imperative. This project continues research into active feedback control of plasma instabilities. Specifically, a new remote suppressor using a small ion beam will be used, which will have minimal perturbation to the system. Robust controllers will also be studied. Applications of these controllers to industrial plasma devices will be explored. Two faculty members and one graduate student will carry out the proposed research using the facilities of the Columbia University Plasma Research Laboratory. The experimental work will utilize the redesigned Columbia Linear Machine.