Kaufman放电室二次电子温度的计算方法研究

THE RESEARCH OF CALCULATING THE SECONDARY ELECTRON TEMPERATURE IN KAUFMAN DISCHARGE CHAMBER

二次电子温度计算是研究Kaufman放电室的核心内容之一。针对Kaufman放电室建立稳态平板非均匀放电模型对二次电子温度进行求解。稳态平板非均匀放电模型从扩散方程出发,重点考虑离子漂移造成的扩散运动和双极性电场对放电室径向密度梯度造成的影响,进一步结合粒子数守恒方程,给出用于求解二次电子温度的方程的解析表达式。代入典型的Kaufman放电室结构参数进行计算的结果表明,用稳态平板非均匀放电模型计算出来的二次电子温度符合实验测量的范围,同时说明在中低压放电条件下,扩散运动和双极性电场是影响放电性能的关键参数。

The calculation of secondary electron is one of the main research content of Kaufman discharge chamber. This paper is aimed at establishing non uniform steady discharge model to solving the secondary electron temperature. Non uniform steady discharge model starts from diffusion equation,we emphases the consideration of the effect of ion dif-fusion motion and ambipolar electron field to discharge chamber radial density gradient. Furthermore,consider the parti-cle conservation equation,it can obtain the analytical representation for solving the secondary electron temperature. Using the typical date of Kaufman discharge chamber,the calculation illustrates that the result of non uniform steady discharge model is according with experiment result,at the same time,it also illustrates that in mid-pressure discharge condition or lower,diffusion motion and ambipolar electric field are the key facts which affects the discharge performance.