Z箍缩等离子体X光辐射能谱的数值模拟研究

The X-ray method is a very important method in Z-pinch high temperature and high density plasma diagnosis. The advance of this method not only has high exactitude but also no interference to plasma. However，the specture decipher involved the complicated problems in theoretics studies and digital methods.There are two primary factors restrict the using of X-ray method to diagnose the Z-pinch plasma. One hand, it is very difficulty to establish a detail atomic model to describe the Z-pinch plasma. The other hand, it is very difficult to solve the equations associate with atomic model, radicalization-transition model, and hydrokinetics model. . Aim at this weakness aspect, the main aim of this study is establish the function relationship between the characters of radiation and Z-pinch plasma, providing a powerful implement and reasonable result to properly apprehend Z-pinch plasma. This work is focus on physical modeling and simulation of Z-pinch plasma implosions and radiation processes. It can acquire the plasma state parameters such as electron temperature, electron density etc based on detail analyze of Z-pinch radiate, synthetically application and numerical calculation of ions at high ionized state, Z-pinch plasma physics, X-ray transition theory and so on.

X光谱学方法是Z箍缩高温稠密等离子体诊断中的关键技术，该诊断方法具有很高的精确度，而且不会对等离子体内部状态产生干扰。目前，限制X光谱学方法在Z-pinch等离子体诊断上应用的主要困难，一方面在于构造多电子原子的细致原子模型和非局域热动平衡等离子体速率方程的求解，另一方面是磁流体力学模型、原子模型和辐射输运模型联合求解在数值模拟上难度大。本课题拟通过对Z箍缩等离子体内爆和辐射过程的物理建模与仿真研究，通过对高剥离态原子结构、等离子体离化平衡状态、等离子体X光谱辐射、输运以及与等离子体相互作用等内容的研究，建立等离子体X光谱辐射特征参量与等离子体电子温度、电子密度、电离化程度、电子能级布居等状态参数之间的函数关系，利用实验测量光谱推断等离子体电子、离子和光子温度等重要信息，为正确认识Z箍缩等离子体状态提供有用的工具。

通过对Z箍缩等离子体内爆和辐射过程的物理建模与仿真研究，针对性地分析等离子体内爆及与辐射相互作用的物理现象，利用实验数据拟合等离子体电子、离子和光子温度等重要信息，为正确认识Z箍缩等离子体状态提供有用工具与合理结果。具体研究内容如下：.　　1．建立基于细致能级模型的非局域平衡（NLTE）等离子体速率方程，计算等离子体辐射的发射和吸收等相关系数；考虑等离子体吸收效应，对辐射与等离子体相互作用而引起的耦合输运过程进行仿真，计算光子场、等离子体温度、密度的时空分布等特征参量。结合Z箍缩实验结果，分析吸收效应对等离子体参数诊断的影响。. 2．对钨丝阵Z箍缩等离子体内爆建立了半经验的合理简化模型，研究了钨等离子体X谱线的展宽效应，特别是Stark展宽与等离子体电子温度和密度的关系，并与离子体速率方程和光子输运方程耦合，研究钨等离子体内爆能量转化、X光辐射能谱特征等；应用实验诊断结果，分析钨等离子体密度、温度等重要信息。