双层丝阵Z箍缩内爆特性研究

The experiments on the Z machine in Sandia National Laboratory show that nested-wire array has a very important role on Z-pinch produced strong X-ray radiation sources and dynamic hohlraum (DH) for the inertial confinement fusion (ICF) researches. However, the physical mechanism of nested-wire array to improve the quality of Z-pinch implosion is not well understood theoretically, it is thus necessary to carry out the theoretical and simulated researches of the characteristics of the nested-wire array Z-pinch implosion.This project will found appropriate dynamic models for the nested-wire array implosion in two dimensional (r,θ) and (r, z) coodinates, and then study its implosion processes, magnetic field and current distributions, and X-ray radiation production. Subsequently, the dynamic characteristics for the different implosion modes of the nested-wire array plasmas will be explored. Thus, the implosion dynamic modes, as well as the relations of the nested-wire array with the generator and load parameters, will be determined. In addition, the physical mechanism to improve X-ray radiation power by using the nested-wire array will be investigated. We will also discuss the related energy conversion and hohlraum wall effects of the nested wire-array plasma on the DH, and judge which implosion mode can generate higher hohlraum radiation temperature. Furthermore, optimized load designs and load parameters will be provided for Z-pinch expriements on the PTS (10MA) device according to above detailed investigation, in order to obtain higher X-ray power in radiation sources and higher hohlraum radiation temperature in Z-pinch driven dynamic hohlraum researches on the PTS device.

Z装置实验表明双层丝阵在Z箍缩产生强X光辐射源和形成动态黑腔辐射场方面有重要作用。但关于双层丝阵的等离子体不稳定性和动态黑腔理论研究尚不深入，有必要开展双层丝阵Z箍缩内爆特性理论研究。项目拟建立二维（r,θ）和（r, z）双层丝阵内爆动力学模型，合理描述双层丝阵内爆过程中丝阵等离子体的运动规律、磁场与电流分布、以及X光辐射；研究双层丝阵不同内爆模式的等离子体动力学特征，确定内爆动力学模式与驱动器和负载参数的关系；研究双层丝阵提高X光辐射功率的物理机制。研究双层丝阵动态黑腔相关的能量加载及黑腔壁特性，判断何种内爆模式下能获得更高的黑腔辐射温度。针对Z箍缩产生的X光辐射功率，提出PTS装置（10MA）双层丝阵优化设计方案及负载参数；针对动态黑腔辐射场，提出PTS装置双层丝阵负载优化设计，为PTS开展双层丝阵实验和动态黑腔物理实验研究提出一系列可行的解决方案。

项目按计划执行，完善了描述双层丝阵等离子体内爆动力学过程的2D（r, ）欧拉三温辐射MHD程序。已掌握了不同内爆动力学模式的双层丝阵Z箍缩实验理论设计方法，经过“强光一号”双层丝阵Z箍缩实验验证，不同内爆模式与负载和电流参数变化密切相关。研制了全电路模拟程序FCM，改进和完善了二维（r, z）三温辐射磁流体力学（MHD）程序-MARED，成功地描述了PTS装置电磁脉冲逐级压缩和功率放大过程。成功地将脉冲功率驱动器全电路模拟程序FCM分别与零维程序、2D（r,theta）欧拉的Zeus程序、以及Z箍缩等离子体辐射磁流体力学程序MARED耦合，为双层丝阵Z箍缩物理实验设计奠定了重要基础。在PTS装置上开展了首次双层丝阵内爆实验，实验结果已表明，在相同充压条件和负载区电流条件下，双层丝阵内爆获得的X功率峰值比单层丝阵的高、脉宽比单层丝阵的窄，初步证明物理设计和理论预估的合理性。利用一维辐射磁流体程序（MARED和CRMHA），开展动态黑腔形成过程和关键影响因素的数值模拟研究。理论预期双层丝阵构形更有利于动态黑腔形成和辐射场的均匀性，初步的PTS实验尝试已经证明其有效性。.项目研究达到预期目标，合理描述双层丝阵Z箍缩不同内爆动力学模式的磁场、电流分布以及等离子体动力学过程，定性判断各种内爆模式产生的条件，以及与驱动器参数和负载参数的关系；认识双层丝阵Z箍缩不同内爆动力学模式的MRT不稳定性发展过程，判断给出最有利于抑制MRT不稳定性的内爆模式；初步认识双层丝阵动态黑腔形成辐射场的物理过程，通过分析研究丝阵等离子体与泡沫转换体的能量加载方式、黑腔壁特性以及泡沫中辐射输运过程等问题，提出改善动态黑腔辐射场温度解决方案。为PTS装置Z箍缩实验提供双层丝阵负载优化设计理论模拟基础。.标注本项目发表的期刊文章8篇、会议文章1篇，参加国际会议交流12人次。获得军队科技进步二等奖一项。