The Steady Struture Of The Wall Erosion Proceeding In H Thrusters

Wall erosion of Hall thruster is the major factor that restricts the lifetime. This paper is to investigate the mechanism of the wall erosion, analyze the erosion stage feature, and provide theoretical basis for the wall erosion of Hall thrusters.Firstly, we discuss the idea and method of structural stability in detail by which we study the morphology evolution of Hall thruster wall erosion. We describe the morphology of the wall erosion evolvement above all, providing the base for the following article. Then we list the problems researchers pay much attention to, especially the anomalous erosion, and we enumerate and analyze the rationality of those points. We propose the method of structural stability by analogy, to study the mechanism of Hall thruster wall erosion.Secondly, we focus on the wall erosion stage feature of the Hall thrusters. We simulate the wall erosion evolvement of the axial pits, draw the evolution of the axial pits, analyze the existence of the axial pits and see whether it grow bigger and bigger. Then we imitate the wall evolution of the azimuthal rectangle groove in the uniform ion bombardment condition, verifying the reliability of the model. We discuss the importance of the three factors by the supposed ion incident condition. Next we simulate the wall evolution of the azimuthal rectangle groove of ion incident condition based on the PIC simulation results. We calculate the axial erosion rates and the azimuthal erosion rates by the calculation results overhead and analyze the erosion stage feature of Hall thruster.After that, we investigate the feedback mechanism of the azimuthal wall evolution in Hall thrusters and propose the feedback mechanism form the basis of the anomalous erosion.Finally, we discuss the mechanism of the basic shape of the anomalous erosion. We can see the groove of anomalous erosion is deeper and deeper, and there is an angle with the axis. We focus on studying the mechanism of those phenomena and analyze the cause by simulate the wall erosion evolution by the ion parameter distribution.