阳极杆箍缩二极管的理论模型及物理特性  

Theoretical modeling and physical characteristics of rod-pinch diode

作　　者：耿力东[1] 谢卫平[1] 袁建强[1] 王敏华[1] 曹龙博 付佳斌[1] 赵小明[1] 何泱[1] Geng Lidong;Xie Weiping;Yuan Jianqiang;Wang Minhua;Cao Longbo;Fu Jiabin;Zhao Xiaoming;He Yang(Key Laboratory of Pulse Power,Institute of Fluid Physics,CAEP,P.O.Box 919-108,Mianyang 621999,China)

机构地区：[1]中国工程物理研究院流体物理研究所脉冲功率科学与技术重点实验室,四川绵阳621999

出　　处：《强激光与粒子束》2018年第8期110-116,共7页High Power Laser and Particle Beams

基　　金：国家自然科学基金项目(11605183);国防科技基础研究项目;中国工程物理研究院流体物理研究所发展基金项目

摘　　要：闪光X射线源是获得高凝聚态物质内部物理图像的重要手段,阳极杆箍缩二极管(RPD)作为其重要组成部分之一,直接影响闪光X射线源照相质量。研究RPD物理特性对二极管物理结构优化设计及实验调试具有重要意义。分析了RPD空间电荷限制、弱箍缩和磁绝缘阶段物理模型。基于PIC模拟技术,编写了计算程序,研究了RPD不同阶段的电子电流、离子电流及电子束箍缩物理特性。通过理论分析,获得了特定几何结构RPD物理模型修正系数及各个阶段离子电流与电子电流比,验证了粒子模拟代码的有效性。模拟结果表明:空间电荷限制阶段,粒子模拟结果与双极性流计算结果一致;在弱箍缩和磁绝缘阶段,粒子模拟得到的总电流与磁绝缘模型计算结果一致,且与文献给出的经验拟合表达式计算结果一致;磁绝缘阶段离子电流与电子电流之比与电压和二极管几何结构相关,给出了离子电子电流比增大系数η与电压和阴阳极半径比的关系,该系数受电子、离子在不同结构二极管渡越时间的影响,随电压和阴阳极半径比增加而逼近恒定值。The rod-pinch diode（RPD）is a cylindrical pinched beam diode being developed as an intense pulsed small diameter bremsstrahlung source for flash X-ray radiography.The studying significance of the physical characteristics lies in optimizing geometry structure of RPD.Using PIC program and numerical simulation,a model of the rod-pinch diode operation based on space limited current at low voltage and self-magnetically limited current at high voltage is researched.Analysis shows that the diode characteristic is determined by space charge limited current at low voltage and self-magnetically limited critical current at high voltage.The simulation result is consistent with reference.Under the special conditions（space charge limited,weakly pinched and self-magnetically limited）,the ratios of ion current to electron current are studied.The coefficient for calculating the self-magnetically limited ion to electron current ratio in the self-magnetically limited condition is affected by the electron and ion transit time and free from the high voltage.

关 键 词：阳极杆箍缩二极管 闪光X射线源 粒子模拟 电子束 箍缩特性 

分 类 号：TL929[核科学技术—核燃料循环与材料]