Theoretical Study And Numerical Simulation Of Large-Scale Pulsed Power Vacuum Device

In recent years, with the rapid developmentof the electromagnetic implosionin thecivil and military applicationsfield, the study of Z-pinch device is carried out in manycountries actively. With the Z-pinch device, high-power electromagnetic implosion canbe achieved, and thus theresearch of physical phenomenaof electromagnetic implosioncan be executed. The transmission efficiency oflarge-scale pulsed power vacuumtransmissionand aggregation device is necessary to be consideredin the Z-pinch devicedesign and manufacturing process. Therefore, It is necessary to implement theoreticalstudy and numerical simulation systematically for such devices. This thesis is aimed atthe theoretical study ofthe magnetically insulated phenomenon which determines thetransmission efficiency oflarge-scale pulsed power vacuum device, andthe PICnumerical simulation studyfor the corresponding devices.This thesis mainly includesthe following parts:1.Finite-difference time-domain method, the macro-particle model, meshgenerationmethod and other basic algorithms are introduced according to thecharacteristics of large-scale pulsed power vacuum devices. Then, the metal rodboundary algorithm, the cyclic symmetry boundary algorithm and thethree-dimensional parallel simulation partition modeling are described emphatically.2．Magnetically insulated transmission line configuration, the magnetic insulationtheory and classification, and the steady-state model of the electron magneticinsulationare introduced. Then, the steady-state theory of the proton magneticinsulationis derived, and the results are compared with the correspondingsimulationresults. The effect of impedance on electron flowis studied, and the result is verified bysimulation.3. The basic structure of four-layer disc conical MITL, and the configuration andcharacteristics of the double post-hole are studied. The magnetically insulatedeffectsand transmission efficiency of the double post-holeare simulated for variousload impedances on the condition of the steady voltage.Then,, the transmissionefficiency ofthe double post-hole and the entire four-layer discconical MITL is studied by simulation withonlyelectron explosive emission andthe corresponding pulse power.4. Module used to calculate the electricity generationfrom the anode surface,electronic energy deposition and temperature raise for electronic deposition “Zeromagnetic zone” in the double post-hole is developed. Then, the energy deposition andtemperature raiseon the anode surface are simulated, and the simulation results areanalysed.5．Secondary electron emission from the metal surface is explored, and module ofsecondary electron emission is developed based on PIC algorithms and is be verifiedby simulation. Then the effect of secondary electron emissionon the double post-hole isstudied by simulation, and the results arediscussed.6．The coaxial MITLwhich is usually adoptedas a transmission device betweenpulse source and load is simulated.Furthermore,a special coaxial MITL with a middlespiral rod as a support structure is simulated, and the effect ofthe middle spiral rod ontransmission efficiency is obtained. The simulation results are analysed.