摘要
目前有关无热子空心阴极(HHC)启动特性的研究多基于常温及以上温度条件,但空间应用的近地轨道典型温度为-65~125℃,开展低温条件的HHC启动特性研究对于分析其受温度敏感影响十分必要。本文完成了HHC设计与辐射温控实验系统搭建,利用真空模拟环境设备,测量了不同初始温度下HHC的启动电流与电压参数,分析研究了HHC点火电压随初始温度的变化规律。实验结果表明,不同初始温度下HHC的点火电压均与帕邢定律定性吻合;但初始温度变化会导致点火电压曲线发生系统性偏移,低温导致向特征值左方向偏移,高温导致向右方向偏移;在低温条件下,点火电压曲线更加陡峭,高温时则趋于平坦;并且在不同启动温度下,最小点火电压基本保持不变。理论分析表明,该偏移现象主要源于温度变化引起的电子与中性粒子非弹性碰撞平均自由程改变,导致帕邢定律对应参数数值变化引起曲线偏移。根据实验结果,本文提出了温度系数来修正理论模型,有效预测出目标温度下的点火电压需求。
Previous studies on the startup characteristics of heaterless hollow cathodes(HHC)primarily focuses on ambient and elevated temperatures.However,considering the typical temperature range(-65 to 125℃)in near-Earth orbit space applications,it is essential to investigate HHC startup characteristics under low-temperature conditions to analyze their temperature sensitivity.This study established an HHC design and radiative thermal control experimental system.Using vacuum environment simulation equipment,the ignition current and voltage parameters of HHC at different initial temperatures were measured,and the variation patterns of the ignition voltage of HHC with initial temperature were analyzed.Experimental results demonstrate that:(1)The ignition voltage curves under various initial temperatures qualitatively conform to Paschen’s law;(2)Temperature variations induce systematic shifts in ignition voltage curves-low temperatures cause leftward shifts toward characteristic values while high temperatures induce rightward shifts;(3)The ignition voltage curve exhibits steeper slopes under low temperatures and flattens at high temperatures;(4)The minimum ignition voltage remains essentially constant across different temperatures.Theoretical analysis reveals that this shifting phenomenon primarily stems from temperature-induced alterations in the mean free path of inelastic collisions between electrons and neutral particles,leading to parameter value changes in Paschen’s law.A temperature coefficient is proposed to refine the theoretical model,enabling the ignition voltage requirements at target temperatures to be effectively predicted.
作者
李智雄
王一白
张仲恺
罗梓浩
孙宇哲
汤海滨
LI Zhixiong;WANG Yibai;ZHANG Zhongkai;LUO Zihao;SUN Yuzhe;TANG Haibin(School of Astronautics,Beihang University,Beijing 102206,China;Key Laboratory of Spacecraft Design Optimization and Dynamic Simulation Technologies of the Ministry of Education,Beijing 102206,China;Beijing Institute of Control Engineering,Beijing 100190,China;School of Space and Earth Sciences,Beihang University,Beijing 102206,China)
出处
《推进技术》
北大核心
2025年第12期256-262,共7页
Journal of Propulsion Technology
关键词
无热子空心阴极
温度敏感性
帕邢曲线
启动特性
电推进
点火电压
Heaterless hollow cathodes
Temperature sensitivity
Paschen curve
Startup characteristics
Electric propulsion
Ignition voltage
