Inductively coupled radio-frequency（RF） plasma neutralizer（RPN） is an insert-free device that can be employed as an electron source in electric propulsion applications.Electron-extraction characteristics of the RP...Inductively coupled radio-frequency（RF） plasma neutralizer（RPN） is an insert-free device that can be employed as an electron source in electric propulsion applications.Electron-extraction characteristics of the RPN are related to the bulk plasma parameters and the device＇s geometry.Therefore,the effects of different electron-extraction apertures and operational parameters upon the electron-extraction characteristics are investigated according to the global nonambipolar flow and sheath model.Moreover,these models can also be used to explain why the electron-extraction characteristics of the RPN strongly depend upon the formation of the anode spot.During the experimental study,two types of anode spots are observed.Each of them has unique characteristics of electron extraction.Moreover,the hysteresis of an anode spot is observed by changing the xenon volume-flow rates or the bias voltages.In addition,the rapid ignited method,gas-utilization factor,electron-extraction cost and other factors that need to be considered in the design of the RPN are also discussed.展开更多
A theory about the dc breakdown process of a gas discharge with thermocathode in a very low pressure(10^(-2) Pa)is provided.The mobility of ions due to ion-neutral charge exchange collisions is mainly responsible for ...A theory about the dc breakdown process of a gas discharge with thermocathode in a very low pressure(10^(-2) Pa)is provided.The mobility of ions due to ion-neutral charge exchange collisions is mainly responsible for the space cumulative effect of positive charges and the formation of the virtual anode.A numerical result for the breakdown process of the argon gas discharge is given.展开更多
基金supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDB23030100)
文摘Inductively coupled radio-frequency（RF） plasma neutralizer（RPN） is an insert-free device that can be employed as an electron source in electric propulsion applications.Electron-extraction characteristics of the RPN are related to the bulk plasma parameters and the device＇s geometry.Therefore,the effects of different electron-extraction apertures and operational parameters upon the electron-extraction characteristics are investigated according to the global nonambipolar flow and sheath model.Moreover,these models can also be used to explain why the electron-extraction characteristics of the RPN strongly depend upon the formation of the anode spot.During the experimental study,two types of anode spots are observed.Each of them has unique characteristics of electron extraction.Moreover,the hysteresis of an anode spot is observed by changing the xenon volume-flow rates or the bias voltages.In addition,the rapid ignited method,gas-utilization factor,electron-extraction cost and other factors that need to be considered in the design of the RPN are also discussed.
基金Supported by National Basic Research Project“Nonlinear Science”the National Natural Science Foundation of Chinathe Theoretic Physics Foundation by Chinese Academy of Sciences(foundation NO.LWTZ-1298).
文摘A theory about the dc breakdown process of a gas discharge with thermocathode in a very low pressure(10^(-2) Pa)is provided.The mobility of ions due to ion-neutral charge exchange collisions is mainly responsible for the space cumulative effect of positive charges and the formation of the virtual anode.A numerical result for the breakdown process of the argon gas discharge is given.
