脉冲等离子体推力器放电室构型参数的影响分析研究

通过开展脉冲等离子体推力器（Pulsed Plasma Thruster, PPT）放电试验，结合理论计算与分析，研究了放电室构型参数对推力器性能的作用机理与影响规律。结果表明：推进剂烧蚀表面附近电极间距的增大使放电电流的峰值降低；增大电极高宽比使电感梯度提高，并使电磁冲量得到提升。考虑到放电电流集中在推进剂表面附近，电流峰值主要受到放电室上游电极间距的影响，因此，采用在放电室下游增大电极扩张角的方法使电极高宽比增大，通过这种空间上的分离，能够解决增大电流峰值与提高电感梯度之间的矛盾，实现推力器电磁冲量的综合提升。相比于常规PPT所使用的矩形推进剂构型，V形的推进剂构型可有效提升推力器的气动冲量。

Analysis and Study on Influence of Discharge Chamber Configuration for Pulsed Plasma Thruster

The mechanism and influence of discharge chamber configuration parameters on thruster performance are investigated by conducting discharge experiments on Pulsed Plasma Thruster (PPT), combining with theoretical calculation and analysis. The results show that the peak value of the discharge current decreases with the increase of the gap between the electrodes near the ablative surface of the propellant. The increase of the aspect ratio of electrodes leads to a higher value of the inductance gradient and a better performance of electromagnetic impulse bit. Considering the discharge current concentrates on the area near the propellant surface, the current peak is mainly affected by the gap between electrodes in the upstream of the discharge chamber. So the method of increasing the electrodes flared angle in the downstream of the discharge chamber is adopted, being aimed to increase the aspect ratio. Such separation could settle the paradox of increasing the current peak value and increasing the inductance gradient and synthetically enhance the electromagnetic impulse bit of PPT. Comparing with the rectangular propellant configuration of the conventional PPT, the V-shape configuration of the propellant could efficiently enhance the gas dynamic impulse bit of the thruster.