摘要
Hollow cathode,with the highest plasma density,current density,and temperature,becomes one of the most important components in the electro-thruster system.As the electric-propulsion thruster performance is directly related to the ionization rate,reliability,and lifetime of the hollow cathode,this paper develops a global model to study the effects of discharge current,gas flow rate,and gas species on the discharge characteristics in the insert and orifice regions of the hollow cathode.The emitter wall temperatures of hollow cathodes predicted by the global model are compared with experimental results from NSTAR thruster neutralization cathodes,confirming the model's validity.The influence of hollow cathode emitter material and structure sizes on the plasma parameters in the internal regions was also evaluated.The simulation results show that there is an optimal matching relationship between the discharge current and gas flow rate to guarantee the maximum ionization rate.The optimal working region for the hollow cathode has been deter-mined under different energetic,regime and structural parameters.The global model established in this paper can quickly determine the key structure and operating parameters of hollow cathode at the design stage,and provide the theoretical basis for hollow cathode design and development.
基金
supported by the National Natural Science Foundation of China (Nos.U22B20120,NSFC52202460 and NSFC52177128)
the National Key R&D Program of China (Nos.2020YFC2201100 and 2021YFC2202804,2022YFB3403504)
the China Postdoctoral Science Foundation (Nos.2021M690392 and 2021TQ0036)
the Advanced Space Propulsion Laboratory of BICE and Beijing Engineering Research Center of Efficient and Green Aerospace Propulsion Technology,China (No.LabASP-2021-04).
