靶丸支撑膜对ICF内爆性能影响的模拟研究

使用二维多群辐射扩散流体力学程序LARED-S，模拟研究靶丸支撑膜在惯性约束聚变氘氘（DD）气体靶内爆过程中的扰动演化过程及其对内爆性能的影响.二维模拟表明：靶丸支撑膜显著降低DD气体靶内爆的中子产额，二维模拟产额为一维结果的55.2%.内爆性能下降的主要物理机制是支撑膜使靶壳生成大幅度的尖钉深入DD气体区，使烧蚀层与DD气体之间物质界面处的电子热传导漏失功率显著增大，导致DD核反应速率显著降低，中子反应速率峰值时刻（bang-time时刻）提前.相比一维理想内爆的模拟结果，支撑膜引入的扰动显著降低bang-time时刻DD气体压强与内爆动能转化为DD气体内能的效率，壳层剩余动能相应大幅增加.

Influence of Capsule Support Tent on ICF Capsule Implosion Performance: Simulation Study

Influence of capsule support tent on ICF DD gas implosion performance is investigated with a two-dimensional radiation diffusion hydrodynamic code LARED-S. It shows that the support tent reduces significantly the neutron yield with a YOC (yield over clean) of 55.2%. The main degradation mechanism is that the capsule shell produces high-amplitude high-density spikes, penetrating deep into the central DD gas. It increases greatly power loss due to electron conduction on the CH/DD interface, leading to the rapid reduction of DD reaction rate and final neutron yield. Compared with one-dimensional ideal implosion simulation result, bang-time of the two-dimensional tent simulation is apparently earlier, and perturbations introduced by the capsule support tent reduce the central pressure and internal energy of DD gas, which is converted from the shell implosion kinetic energy.