引入守恒格式的自相似解进行ICF辐射驱动时变对称性分析

引入守恒格式的自相似解计算黑腔X射线能流时空分布，通过视角因子方法计算靶丸表面入射能流分布，从而进行惯性约束聚变辐射驱动时变对称性分析。分析了光斑运动、激光脉冲波形及靶丸装配偏差对靶丸辐照均匀性的影响。以二阶分量时间积分值为优化目标，最佳腔长计算值与内爆对称性调节实验结果相符，内爆腔靶组合参数扫描得到的最佳长径比与NIF目前实验值相当，模型有效性得到验证。

Analysis of time-dependent radiation symmetry in ICF based on self-similar solution

With the self-similar solution of X-ray confinement in cavity, the time-dependent redistribution of thermal X rays inside the hohlraum is calculated. Distribution of radiation power intensity on the capsules surface is calculated via the view-factor method. After that, the time-dependent radiation drive symmetry of the capsule could be studied. The effects of motion of laser spots, laser pulses and pointing error of capsule on the radiation uniformity are analyzed. Multi parameter couples are scanned to reach the minimum of time-integrated value of the second coefficient of Legendre polynomials. The best lengths of hohlraum agree with the results of implosion symmetry tuning experiments on SG-Ⅱ and SG-Ⅲ prototype laser facilities. The best length-to-diameter ratio of hohlraum is close to the point design targets on the National Ignition Facility (NIF). The validated model may give some reference to the future experiments design and analysis of implosion symmetry.