复杂同轴线场分布的有限元分析与仿真

复杂同轴线问题是一类具有不规则边界的复杂二维边值问题。针对这类问题,运用有限元法(FEM)并借助于Matlab/PDE Toolbox对其场分布进行了分析与仿真,得到了椭圆同轴线、偏心同轴线和圆方同轴线的等电位线和电场线分布,从而得到了形状误差、偏心误差对普通同轴线的场分布影响的定量结果,进而讨论了他们的工程应用背景。     

工程电磁场综合实验设计

为了提高学生的学习兴趣,综合掌握工程电磁场基本原理,基于静电场等电位线绘制实验,本文设计了一项工程电磁场综合实验。实验室在原先实验内容基础上增加两个内容。一是增加电磁场数值计算实验,即用电磁场数值分析软件分析五种电极板中等电位线和电场线等。二是增加了悬浮导体电位的计算实验。通过该实验进一步提高学生的工程电磁场基本知识和灵活运用工程电磁场概念的能力。     

微带型曲折线慢波结构的研究

本文对微带型双列曲折线慢波结构中的场进行了分析。用数值求解法计算了电位函数U(y,z)和特征导纳Yc,推导出曲折线的色散方程和耦合阻抗表达式,并利用电子计算机计算了不同结构参量的曲折线特性。由此法所设计的二组曲折线已用于印制电路行波管中。实验结果与理论计算比较一致。     

静电磁场中存在悬浮电磁导体时的三维场计算

本文讨论了表面密度法在静电磁场数值计算中的应用。给出了在有源场中有多孤立悬浮电位或磁位的导体或导磁体存在情形下静电磁场问题的解。对于磁控反应离子刻蚀机中磁场分布和点电荷产生的电场中的导体电位等问题进行了计算并与实验结果相比较,两者符合得很好。本文提出的方法适用于任何悬浮电位或磁位的导电体或导磁体电位或磁位的计算。     

场线绘制方法的讨论

在电磁场课程中,绘制场线具有比较重要的理论和实际意义,同时还是进行研究型教学的良好载体.本文以电场线为例讨论了绘制电磁场场线的3种方法:自适应步长法、自适应方向法和切线方向法,并介绍了这3种方法的基本思想,定性和定量对其进行了比较.     

TFSOI RESURF器件电势和电场分布的解析研究

在物理模型的基础上,对ＴＦＳＯＩ ＲＥＳＵＲＦ器件的电势和电场分布进行了解析分析,系统研究了漂移区掺杂浓度,漂移区长度,埋层ＳｉＯ２厚度和ＳＯＩ层厚度等结构参数同电势和电场分布的关系,并首次定量分析了在工艺加工过程中必须引入的场ＳｉＯ２界面电荷密度的影响。解析计算结果同ＭＥＤＩＣＩ模拟结果相符。     

UWB,HEMP作用下长线缆场线耦合效应比较研究

为详细研究UWB(超宽带)、HEMP(核电磁脉冲)作用下长线缆的场线耦合效应问题,并将二者进行比较,依据场线耦合效应计算的Agrawal、Vance模型,推导了能有效用于场线耦合效应编程计算的实用算式.在此基础上编写了Matlab计算程序,对UWB和HEMP作用下长线缆的场线耦合效应进行了计算、分析和比较,得出了两种强场作用下的效应规律.计算显示,UWB和HEMP都能在线缆上激励较高的电流脉冲,也能在线缆端部激励较强的干扰电压脉冲;在相近条件下,UWB激励的响应弱于HEMP;二者相比,其场线耦合效应既有相似之处,又有不同的特点.     

功率LDMOS中的场极板设计

本文提出了LDMOS器件漂移区电场分布和电势分布的二维解析模型,并在此基础上得出了LDMOS漂移区电势分布和电场分布的解析表达式。通过表达式的结果,研究了多晶硅场板的长度和位置对于器件表面电场和电势的影响,解析结果与MEDICI结果相符。     

有限差分法求解静电场问题

简介了有限差分法（FDM）的起源,讨论其在静电场求解中的应用.以铝电解槽物理模型为例,采用FDM对其场域进行离散,使用MATLAB和C求解了各节点的电位.由此,绘制了整个场域的等位线和电场强度矢量分布.同时,讨论了加速收敛因子对超松弛迭代算法迭代速度的影响,以及具有正弦边界条件下的电场分布.     

基于OFI线偏振光激励等离子体的电子能量分布讨论

在准静态隧道电离理论模型和准经典阈上电离理论模型的基础上 ,建立了一个描述线偏振光场电离电子能量分布的简单模型 ,推导出了既易于理解又相对简单适用的描述线偏振光场的电子能量分布函数解析表达式。数值计算了类硼氮系统的电子能量分布曲线 ,并对计算结果进行了分析。最后与现有实验结果进行比较 ,给出其适用范围。     

强流相对论电子束的纵向自群聚

当一束强流相对论电子束穿过一系列等距离排列的等电位导体,如导电或导电栅网时,由于空间电荷效应,将在纵向形成周期性空间电荷静电场,此民场将使强流相对论电子束纵向群聚,本文对这一非线性物理过程进行了理论和粒子模拟计算,基于此机理,有可能研制出一类新型的高功率微波器件。     

电磁兼容天线参数定义及其相互关系

运用图示法简述了电磁兼容天线参数的基本概念。给出了在电磁兼容测量中,EMC 天线参数之间的相互关系及其计算公式,如天线系数和发射天线系数的计算、功率密度和电场强度的计算、天线辐射场强的计算、功率与电压之间的转换计算和功率密度与电场强度之间的转换计算等等。     

Mean lifetime calculations of quantum well structures: a rigorousanalysis

A matrix method that is applicable to an arbitrary potential variation represented by a set of linear functions such as multiple quantum well structures in the presence of a static electric field is described. An analytical expression for the mean lifetime of the quasi-bound state of a single quantum well in the presence of a static electric field is obtained     

An Analysis of Magnetic Field Environment Near High-Voltage Power Lines and Contact Wires of Electric Railways

Introduction With the development of electric power systems, electric railways and electric equipment, the electromagnetic field produced by them in the near area and the biological effects on man are studied. According to the recent report, the magnetic…     

An Analysis of Magnetic Field Environment Near High-Voltage Power Lines and Contact Wires of Electric Railways

Image method is used in this paper to calculate the value of magnetic field near high-voltage transmission lines and electric railways. Areas in which the magnetic field is less than 0.002 Gauss are given and the magnetic pollution of high-voltage power transmission lines and electric railways is discussed     

Equations of motion for a free-electron laser with an electromagnetic pump field and an axial electrostatic field

The equations of motion for a free-electron laser (FEL) with an electromagnetic pump field and a static axial electric field are derived using a Hamiltonian formalism. Equations governing the energy transfer between the electron beam and each of the electromagnetic fields are given, and the phase shift for each of the electromagnetic fields is derived from a linearized Maxwell wave equation. The relation between the static axial electric field and the resonant phase is given. Laser gain and the fraction of the electron energy converted to photon energy are determined using a simplified resonant particle model. These results are compared to those of a more exact particle simulation code.     

基于拉氏方程的舰船静态电场深度换算

 从舰船静态电场的物理特性出发,对其在深海环境下的深度换算方法进行研究,提出基于拉氏方程的静态电场深度换算方法.利用该方法可实现静态电场的某分量向较大深度处自换算;由场垂直分量向较大深度的其他分量互换算以及由水下标量电位向较大深度的电场各分量的换算.以单个水平电偶极子的场为计算原型,以互换算为例对换算方法进行了仿真验证,通过对换算误差的分析,表明该换算方法是可行的.换算方法对实际舰船的静态电场的分布研究具有现实意义.     

Penetration of fields through a circular hole in a wall of finitethickness

Consideration is given to a uniform, static electric field on one side of a plane metallic wall of finite thickness with a circular hole. The field induces a charge distribution on the metallic surface which behaves, at large distances from the hole, as a dipole moment, with different values for the polarizability on the inside (same side as the driving field) and outside surfaces of the hole. Two integral equations are derived for the potential in the hole and variational forms are constructed for the symmetric and asymmetric polarizabilities. Trial functions with adjustable parameters lead to accurate numerical values for the inside and outside polarizabilities. A similar approach yields corresponding values for the inside and outside magnetic susceptibilities     

Spindt三极管静电场分析

本文利用计算机数值分析，得到了一组Ｓｐｉｎｄｔ三极管的发射尖端几何因子的计算公式；计算了器件内的场分布，对一组较典型的结构参数绘出了等势线。     

Electric field effects on an optically-pumped HCOOH FIR laser and Zeeman laser theory

Electric field effects have been investigated on the output power of six far-infrared (FIR) laser lines from H¹²COOH optically-pumped by a CO₂ laser with its polarization arranged perpendicular to the Stark field. Optoacoustic signals observed on the pump lines were hardly affected by the applied electric field up to 0.6 kV/cm. By neglecting the electric field effects on the pump transitions, Zeeman laser theory has been applied to the FIR laser transitions. Numerical calculation predicts the observed FIR output power as a function of electric field. Experessions for oscillation frequency and intensity in homogeneous limit are given, which may be applicable to any FIR Stark laser so far as the pump transition is free from electric field effects.