基于高对称性驱动线圈的高效电磁驱动磁通压缩关键技术研究

At present, electromagnetic flux compression is one of the most efficient techniques for the production of ultrahigh magnetic fields (> 300 T) in a large space. However, the inherent problems of low energy conversion efficiency and liner implosion asymmetry of this technique result that it is very difficult to further increase magnetic field. To overcome these problems, a novel high efficient electromagnetic flux compression technique based on highly symmetrical driving coils is proposed, where the high symmetrical driving coils based on a unique multi-layer solenoid of close-packed thin wires are introduced to completely solve the problem of liner implosion asymmetry and further increase the energy conversion efficiency, which will make the new technique be able to generate higher magnetic field under the same power supply. The project will mainly study: 1) the design and fabrication method of the high symmetrical driving coils, the electromagnetic implosion behavior and energy conversion rule of liner driven by the highly symmetrical driving coil; 2) 2D numerical model of electromagnetic flux compression using the current filament method. This study will offer a necessary technical support to the extreme physics research to meet the requirement for higher magnetic field.

电磁驱动磁通压缩技术是目前最有效地在较大空间范围内产生超强脉冲磁场（> 300 T）的方法，但是该技术固有的能量转换效率低和套筒内爆不对称问题，导致其难以进一步提高磁场强度。针对上述问题，本项目创新性地提出一种基于新型高对称性驱动线圈的高效电磁驱动磁通压缩新技术。该技术中的驱动线圈采用独特的多层密绕复合螺线管结构，能够彻底解决套筒内爆不对称问题，并进一步提升能量转换效率，从而在相同储能下获得更高的磁场。本项目拟重点开展：1）高对称性驱动线圈设计方法、制作工艺及在其驱动下套筒电磁内爆压缩行为和能量转换规律的研究；2）基于电流丝法的二维电磁驱动磁通压缩过程的数值模拟方法的研究。本项目的开展能够为极端物理研究提供必要的技术支撑，以满足其对磁场强度越来越高的要求。

本项目针对现有电磁驱动磁通压缩技术存在的套筒内爆不对称和能量转换效率低等问题，深入开展了一种基于多层密绕螺旋结构的高对称性驱动线圈的高效电磁驱动磁通压缩新技术研究。首先，完成了高对称性驱动线圈设计方法及制作工艺研究，成功研制出了具有无馈流缝隙特点的高均匀性驱动线圈；其次，完成基于电流丝法的电磁驱动磁通压缩过程的数值模拟方法研究，对比发现该数值模型能够较好地预测中前期的金属套筒内爆行为；最后，完成了高对称性线圈驱动下套筒电磁内爆压缩行为的研究，研究结果证实了采用多层密绕螺线管结构的驱动线圈能够较好地解决套筒内爆不对称问题，并能够进一步提升能量转换效率。本项目研究结果为利用电磁驱动磁通压缩技术获得更高磁场提供一种切实可行的路线，也为后续电磁驱动磁通压缩技术实现1000T级磁场提供了有力的技术支撑。