Research On Initiation Process Of Heartless Hollow Cathode Based On Emission Spectrum

The hollow cathode as a vacuum electron source is a critical component in plasma propulasion,plasma contactor and micro-thrμster.The heartless hollow cathode eliminates the traditional heater structure and has the characteristics of high starting speed,simple structure,and high reliability.By monitoring the plasma parameters and temperature field during the initiation process,it is helpful to understand the physical mechanism of the entire initiation process,studying the changes in the corrosion yield under different modes and the effects of different starting conditions on the initiation process and corrosion,which will help optimize the initiation.First,the structure of the hollow cathode is modified to facilitate the collection of the spectral information of the plasma inside the hollow cathode,and a high-speed camera is μsed to study the plasma variation of the ms level,according to the LTE spectrum model combined with the Kuro camera pre-filter acquisition specific Spectral information in the form of band was μsed to study the spatial distribution of the plasma in different modes of the initiation process,and the oscilloscope is μsed to monitor the VI characteristics of the initiation process in different time scales.Comsol is also μsed to simulate the initiation process.The evolution of ion characteristics at different starting conditions was studied.Based on the monochromatic temperature measurement method,a set of transient measurement methods suitable for the spatial distribution of hollow cathode space temperature was analyzed.The principle of the heat conduction of plasma heating during the initiation process was analyzed.The multi-physics coupling model was μsed to analyze the evolution of thermal deposition during startup.Laws were studied to explore the effects of anode current and gas flow on temperature distribution and evolution.A set of experimental programs and later data processing methods for real-time monitoring of the ablation yield in the initiation process are designed to study the influence of different factors on the corrosion yield,and the corrosion mechanism and corrosion position are analyzed by means of simulation.Through the improvement of the hollow cathode initiation circuit and the improvement of the air supply mode,the hollow cathode can more successfully ignite and reduce the emitter corrosion yield.