Simulation Study On Output Characteristics Of Multi Beam Hollow Cathode Electron Gun

Compared with other different types of electron guns,hollow cathode electron gun has the advantages of simple structure,higher current density of the output electron beam,high beam pulse width,plasma generated by the discharge will not directly bombard the cathode and electron beam self-clustering.Relying on these advantages,it has become the most widely used particle source of high power microwave source,and plays an important role in promoting the development of high power microwave technology.And because of its high density ionization output,it is considered to be applied to the study of millimeter wave and terahertz band.The research of hollow cathode electron gun is mainly divided into simulation and structural design optimization.In the aspect of simulation,it is mainly aimed at the demonstration of hollow cathode discharge mechanism and the study of output characteristics of electron beam under different conditions.In this thesis,the simulation of multi beam single gap hollow cathode electron gun is studied.The main work contents are as follows:1.The advantages,disadvantages and basic principles of several types of electron guns widely used at present are introduced,and the advantages of hollow cathode electron guns are briefly analyzed.Aiming at the research status of hollow cathode electron guns at home and abroad,the simulation and physical experiments are expounded.2.Briefly summarize the gas discharge theory and the basic theory of plasma,write the simulation program,and carry out the geometric modeling and electromagnetic field modeling of electron gun.3.A series of multi beam hollow cathode electron guns under different working conditions are simulated,and the process of hollow cathode discharge is simulated by PIC / MCC.The effects of different cathode hole numbers on the parameters of the output electron beam are analyzed,the relationship between the peak current growth rate of the electron beam and the number of cathode holes is qualitatively analyzed,and the current of each electron beam under different conditions is calculated.4.The multi beam strip hollow cathode electron gun is simulated,the influence of rectangular cathode hole on discharge is analyzed,and the current of each electron beam is calculated.The work of this thesis lays a foundation for the further research of multi beam hollow cathode electron gun.