| At present, based on the global ITER plan, more and more countries all over theworld are involved in the research of neutral bunch of injection plasma thermonucleartechnology. Due to the high neuter efficiency of negative hydrogen ion(H-), negativehydrogen ion source has been crucial to thermonuclear experiment. Therefore, it hasfar-reaching significance for the research of negative hydrogen ion source. In order tofill the domestic blank for the simulation research of negative hydrogen ion source andcatch up with the abroad level, this proposed paper aims to develop an algorithm of thefull3D particle-in-cell plus Monte Carlo collision, and study the discharge propertiesof negative hydrogen ion source. This thesis mainly includes the following parts:1. Application of Monte Carlo method in the Foil and numerical calculation of therectangular permanent magnet. The process of the collision between electron and theFoil is theoretically analyzed. In CHIPIC flat, a full3D Foil calculation module isdeveloped based upon the Monte Carlo method and the empirical scattering formula,which is proved by virtual cathode oscillator. With the finite difference method, thepermanent magnet difference formula is deduced under the rectangular coordinatesystem, which is compared with the result of theoretical calculation.2. Study of a full3D PIC/MCC simulation algorithm for the electron energydeposition in the discharge process of negative hydrogen ion source. Based on theanalysis of the plasma physics mechanism in negative hydrogen ion source, thefundamental techniques of PIC and MCC algorithm are studied respectively and thehighly efficient storage method is designed. With the plasma potential and coulombcollisions, the full3D PIC/MCC algorithm of the electron energy deposition isdeveloped, which is proved by overseas experiment.3.3D optimized simulation of JAERI10A ion source and exploration of volumeproduction mechanism. The reason of electron space is non-uniform in the JAERI10Amulti-cusp ion source is explored, and two schemes about space uniformityoptimization are put forward. The volume production efficiency of H-is analyzed interms of various factors, such as pressure, filter magnetic field, discharge electrode location and initial discharge energy. And then, the optimized scheme of parameters inion source is acquired.4. Study of the discharge mechanism of J-PARC ion source and the multi-cusoproton source. The space and energy distribution of electron in multi-cusp protonsource is revealed. And then, the discharge characteristic of J-PARC ion source isanalyzed, and the efficiency of volume production influnenced by the position ofcorrect magnet is discussed. These studies give a theoretical guidance for thedevelopment of domestic ion source.5. Development of the full3D PIC/MCC algorithm for neutral particlestransmission and H-surface production. Neutral particles transmission mechanism istheoretically analyzed. The ionization process, charge exchange collision, theinteraction between the boundary and the hydrogen atoms are taken intoaccount. The H-surface-produced physical mechanism in the negative hydrogen ionsource is improved and developed. A full3D program for the simulation of neutralparticles transmission and H-surface production is developed, which has been provedby overseas achievements.6. Study of the H-surface production in JAERI10A ion source and thedevelopment of the H-extraction algorithm. The electron energy deposition and theneutral transmission module combined as an organic whole and the process from thebeginning of discharge to H-surface production of negative hydrogen ion source issimulated, which indicate the cause of H-spatial non-uniformity. The surfaceproduction efficiency of H-is analyzed in terms of several factors, such as wallmaterials, temperature of H+, and yield function. In addition, a numerical simulationalgorithm for H-extraction process is designed, and the different pressure effect on H-extraction efficiency in the JAERI10A ion source is discussed.
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