等离子体中电波传播的三波非线性效应仿真研究

发布时间：2018-04-10 23:10

本文选题：三波非线性 + 等离子体　；参考：《西安理工大学》2017年硕士论文

【摘要】：飞行器在返回大气层时,其速度可达到十几甚至数十马赫,高温使其周围空气电离形成等离子鞘,使得投射其上的电磁波产生反射、折射及散射,而在其中传播的电磁波受到衰减,从而影响飞行器的导航、遥测和通信信号的传输,严重阻碍飞行器与外界的通信,影响飞行器的安全。为了解决这一问题,国内外研究人员提出了许多可能的解决办法,至今仍未彻底解决。等离子体的三波非线性效应是其中的一种可能的解决方案。本文对等离子体中的三波非线性效应进行研究,具体的工作如下:(1)首先介绍论文的研究背景与意义,然后介绍了等离子体中的流体力学方程,结合麦克斯韦方程组建立等离子体与电磁波相互作用过程的数学物理模型。(2)开展等离子体中的三波非线性效应的频域数值仿真研究。主要是对修正的金兹堡方程及非线性电流进行求解,分析低频信号入射角、泵源参数及等离子体电子密度分布对非线性的影响;最后,给出RAM C实际等离子体电子密度分布下的仿真结果。(3)开展等离子体中三波非线性效应时域算法研究。为了更直观地分析非线性电流项,采用JEC-FDTD方法进行计算;同时,为了节约计算时间,在C#环境下结合CUDA实现并行编程。最后,对RAM C实际等离子体电子密度分布下的非线性效应进行分析,并与频域的计算结果相对比,分析三波非线性效应的实际应用条件。论文的分析可为三波非线性效应抑制“黑障”系统确定关键技术参数,包括泵源功率、频率、安装位置/方式的需求,为系统方案的设计和工程应用提供理论依据。
[Abstract]:When an aircraft returns to the atmosphere, its velocity can reach a dozen or even tens of Mach. The high temperature ionizes the surrounding air to form a plasma sheath, which causes the electromagnetic waves projected on it to produce reflection, refraction and scattering.However, the electromagnetic wave propagating in it is attenuated, which affects the navigation, telemetry and communication signal transmission of the aircraft, seriously hinders the communication between the aircraft and the outside world, and affects the safety of the aircraft.In order to solve this problem, researchers at home and abroad have put forward many possible solutions, which have not been solved completely.The three-wave nonlinear effect of plasma is one of the possible solutions.In this paper, the three-wave nonlinear effect in plasma is studied. The main work is as follows: (1) the background and significance of this paper are introduced first, and then the hydrodynamic equations in plasma are introduced.A mathematical and physical model for the interaction between plasma and electromagnetic wave is established by using Maxwell's equations. (2) numerical simulation of three-wave nonlinear effect in plasma in frequency domain is carried out.The modified Ginzburg equation and nonlinear current are solved, and the influence of incident angle of low frequency signal, pump parameters and plasma electron density distribution on nonlinearity is analyzed.The simulation results of RAM C plasma electron density distribution are given.In order to analyze the nonlinear current term more intuitively, the JEC-FDTD method is used to calculate the nonlinear current term, and in order to save computing time, parallel programming is realized with CUDA in C # environment.Finally, the nonlinear effect under the electron density distribution of RAM C plasma is analyzed, and compared with the calculated results in frequency domain, the practical application conditions of the three-wave nonlinear effect are analyzed.The analysis of this paper can determine the key technical parameters of the system, including pump power, frequency, installation position / mode, and provide the theoretical basis for the design and engineering application of the system.
【学位授予单位】：西安理工大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TN011;O53

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