Experimental and Theoretical Research on Dense Z-Pinches

从实验和理论上研究了等离子体聚焦、致密薄片和气体喷发的Z箍缩现象。主要研究结果如下：(1)致密等离子体聚焦产生的中子产额远高于中等能量放电等离子体聚焦装置的定标规律。(2)建立了Z箍缩、等离子体聚焦和喷气Z箍缩的模拟程序。(3)到目前为止，详细研究了各种参数对等离子体聚焦最佳条件的影响，但几乎没有系统地研究阴极效应。结果表明，结构差异对聚焦的最佳条件有明显影响。(4)为了抑制常规柱形Z箍缩中的不稳定性，提出了密集片状Z箍缩。给出了无限宽理想薄板Z箍缩的基本特征。实际的薄片Z收缩有两种类型--拉伸型和压缩型。在拉伸型薄片Z箍缩实验中，在合适的初始压强范围内产生了薄片Z箍缩等离子体。

The plasma focus, dense sheet and gas-puff z-pinches were investigated experimentally and theoretically. Main results are the following :(1) The compact plasma focus gave neutrons yield that was much more than that implied in the scaling law obtained in the plasma focus devices with medium discharge energy.(2) The Simulation codes of necking of z-pinch, plasma focus and gas-puff z-pinches were created.(3) The influence of the various parameters to the optimum condition of plasma focus has been studied in detail so far, but cathode effects have hardly been studied systematically, in the present research, the two types of cathodes - grid-like cathode consisted of sixteen Cu bars and cylindrical tube cathode - were applied to the plasma focus device. It was shown that the structural difference clearly affected the optimum condition of focus(4) To suppress the instabilities in conventional cylindrical z-pinches, the dense sheet z-pinches were proposed. The basic features of ideal sheet z-pinch with infinite width were given. There are two types of real sheet z-pinches - the stretched and compressional types. Their stability and the possibility as fusion plasma were examined.(5) in the experiment on the stretched-type sheet z-pinch, the sheet z-pinch plasma was created at the appropriate initial pressure region.