The ion velocity distribution functions in the near-wall region of a high-power, 9-kW class magnetically shielded Hall thruster are experimentally characterized to quantify the degree to which the discharge chamber walls are shielded from ion bombardment. Ion velocity measurements are performed at a discharge voltage of 300 V and a discharge current of 15 A using laser-induced fluorescence along the centerline and discharge chamber walls. The centerline results show that the location of the acceleration region exists downstream of the exit plane of the thruster, which is consistent with previous measurements on other magnetically shielded thrusters. Measurements performed in the near-wall region show that ions are moving approximately parallel to the walls up to the exit of the thruster; however, a small but finite maximum mean velocity of 0.2 km s −1 is directed toward the discharge chamber walls. A sheath analysis is performed to define a critical electron temperatur...

中文翻译：

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磁屏蔽霍尔推力器的非侵入式原位测量近壁离子动能

实验表征了大功率9 kW级磁屏蔽霍尔推力器近壁区域中的离子速度分布函数，以量化放电室壁免受离子轰击的程度。沿中心线和放电室壁使用激光诱导的荧光，在300 V的放电电压和15 A的放电电流下进行离子速度测量。中心线结果表明，加速区域的位置位于推进器出口平面的下游，这与先前在其他磁屏蔽推进器上的测量结果一致。在近壁区域进行的测量表明，离子正以近似平行于壁的方向移动，直到推进器的出口为止。但是，最大平均速度很小但有限，为0。2 km s -1指向放电室壁。进行鞘层分析以定义临界电子温度。