激光非均匀性对内界面变形影响的数值模拟  

Numerical simulation of effect of laser nonuniformity on interior interface

作　　者：郁晓瑾[1] 吴俊峰[1] 叶文华[1] 

机构地区：[1]北京应用物理与计算数学研究所,北京100088

出　　处：《强激光与粒子束》2007年第8期1283-1286,共4页High Power Laser and Particle Beams

基　　金：国家863计划项目资助课题;国家自然科学基金资助课题(10475011;10225105)

摘　　要：使用LARED-S程序，参照NIF直接驱动DT点火靶，模拟研究了激光非均匀性对高收缩比球内爆内界面变形的影响。2维数值模拟计算表明：直接驱动高收缩比内爆对驱动激光非均匀性非常敏感，内界面流体不稳定性的发展严重破坏靶丸的对称压缩，使中心热斑的体积显著减小。以最大压缩时扰动增长幅度不超过热斑半径的1／3为限，模拟给出不同模数的低阶扰动模（模数小于等于12）对驱动激光均匀性的要求在2．5％～0．25％之间，其中模数在8～10之间的扰动模对激光功率均匀性的要求最严格，约为0．25％。Using the LARED-S code and referring to the NIF direct-drive DT ignition target, the effect of laser nonuniformity on the interior interface in direct-drive spherical implosion with high convergence ratio was numerically studied. The two-dimensional results show that the implosion with high convergence ratio is sensitive to the nonuniformity of driving laser, and the growth of hydrodynamic instability on interior interface destroys the symmetric-drive and reduces the volume of central hot spot observably. Taking the limit that perturbation amplitude is equal to 1/3 radius of central hot spot, the simulation also gives that the requirements for the laser uniformity for different mode number（less than 12） on simple physical model are between 2.5 % 0.25%, and the modes between 8-10 have the most rigorous requirement which is about 0.25%.

关 键 词：惯性约束聚变 流体不稳定性 收缩比 非均匀性 数值模拟 

分 类 号：O361.5[理学—流体力学] O242.1[理学—力学]