钡钨空心阴极放电等离子体特性实验研究

Experimental investigation for discharge plasma properties of BaW hollow cathode

空心阴极作为电推力器的核心部件之一,其放电等离子体特性对空心阴极的性能和可靠性具有决定性的作用。采用实验的方法,使用朗谬尔静电探针置于钡钨空心阴极放电出口处,诊断和分析了钡钨空心阴极出口处的放电等离子体特性随阴极推进剂流量和放电电流的变化规律,结果表明:阴极推进剂流量和放电电流对空心阴极放电等离子体特性具有比较明显的影响,各等离子体参量随阴极推进剂流量和放电电流均有明显的变化,其中,电子数密度随阴极推进剂流量和放电电流的增大而上升,等离子体电势随阴极推进剂流量和放电电流的增大而下降,电子温度随阴极推进剂流量的增加而下降,随放电电流的增大有略微升高,而且,放电电流对放电等离子体特性具有更显著的影响。

As a key part of electric thruster,its hollow cathode discharge plasma properties decide its performance and reliability.In the experiments,a Langmuir Probe was placed at the BaW hollow cathode orifice to diagnose and analyze the variation of discharge plasma properties at the BaW hollow cathode orifice with the propellant flow and discharge current.The experiment results show that the propellant flow and discharge current have an obvious effect on discharge plasma properties,and each plasma parameter has an obvious change with the propellant flow and discharge current.Concretely speaking,the electron density increases with the increase of propellant flow and discharge current,the plasma potential decreases with the increase of propellant flow and discharge current,and the electron temperature reduces with the increase of propellant flow but increases a little bit with the increase of discharge current.The discharge current has more obvious effect on the plasma properties.