Confinement characteristic of primary electrons with the variation of channel width in the discharge chamber of annular ion thruster

In this paper,the confinement characteristic of primary electrons in the non-axisymmetric discharge chamber of annular ion thruster is investigated by a three-dimensional(3 D)non-self-consistent particle tracking model with Monte Carlo Collision(MCC)method.The results show that:The density of primary electrons upstream of ion optics on cathode axis is about 5–50 times higher than that of the other side,which means that the density of primary electrons is obviously non-axisymmetric.The channel width has a significant effect on the average density and uniformity of primary electrons.The average density can be increased by nearly 1.5 times under the appropriate channel width,meanwhile,the variance of density distribution can be reduced by more than 2 times.This is because that increasing the channel width can improve the average confinement length of primary electrons greatly.Furthermore,there is an infection point in the increase of primary electron average confinement length with the channel width,which caused by the significant change of magnetic field structure.Under the case after the inflection point,primary electron mainly(more than 50%)moves to the channel center,which makes the average confinement length of primary electrons and their number in the discharge chamber increase largely.

环型离子推力器研制发展综述

环型离子推力器的研制发展,为离子推力器在未来航天任务中广泛应用提供一个良好平台。相比传统型离子推力器,环型离子推力器设计概念更为新颖。环型离子推力器增大放电室内部的放电阳极面积、降低离子光学系统溅射腐蚀,并提高了推力器的功率水平和运行寿命。在调研国外环型离子推力器研制基础上,结合环型离子推力器早期发展、现阶段技术特点、研究现状和未来发展趋势等方面的研究,为未来新型高功率离子推力器的研制提供了一定的参考价值。

环型离子推力器放电机理研究进展

环型离子推力器是未来大功率电推力器中一个极具潜力的发展方向,将来有望广泛用于探月与载人航天、火星探测等深空探测任务。介绍了环型离子推力器的特点、优势和价值,指出了目前阻碍环型离子推力器发展及应用的关键问题。为了研究环型离子推力器的放电机理,综述了环型离子推力器放电室设计参数,如几何参数、电磁场参数和推进工质分布等,以及对其放电特性的影响;重点介绍了环型离子推力器与传统考夫曼型离子推力器相比差异较大的实验现象。在此基础上,介绍了环型离子推力器放电机理的数值模拟研究现状。最后,对环型离子推力器放电机理的研究及下一步发展进行了展望。

环型离子推力器放电室参数对推力器性能的影响

环型离子推力器放电室参数对其推力和比冲等具有显著影响。利用基于混合宏粒子(Hybrid-PIC)解耦迭代算法,对环型离子推力器稳态放电过程进行了三维仿真模拟,发现放电室参数对推力器的推力、比冲、放电损耗、电离率以及放电室出口处离子分布均匀性均会产生影响。研究结果表明,增大环型离子推力器阴极长度,会使原初电子和等离子体在阳极壁面的损失减少,均匀性提高;增加磁体个数对原初电子的自由运动范围影响很小,因而对等离子体分布影响也很小;增大放电室通道宽径比可以增大原初电子的自由运动范围,提高原初电子和等离子体的均匀性。减小放电室内径对原初电子和等离子体的影响更显著。因此,5 kW环型离子推力器的阴极长度应选设计长度的1.5倍,通道宽径比应选设计值的1.2倍。