Code O-SUKI: Simulation of direct-drive fuel target implosion in heavy ion inertial fusion

The Code O-SUKI is an integrated 2-dimensional (2D) simulation program system for a fuel implosion, ignition and burning of a direct-drive nuclear-fusion pellet in heavy ion beam (HIB) inertial confinement fusion (HIF). The Code O-SUKI consists of the four programs of the HIB illumination and energy deposition program of OK3 (Comput. Phys. Commun. 181, 1332 (2010)), a Lagrangian fluid implosion program, a data conversion program, and an Euler fluid implosion, ignition and burning program. The OK3 computes the multi-HIBs irradiation onto a spherical fuel target. One HIB is divided into many beamlets in OK3. Each heavy ion beamlet deposits its energy along the trajectory in a deposition layer depending on the particle energy. The OK3 also has a function of a wobbling motion of the HIB axis oscillation, and the HIBs energy deposition spatial detail profile is obtained inside the energy absorber of the fuel target. The spherical target implosion 2D behavior is computed by the 2D Lagrangian fluid code coupled with OK3, until just before the void closure time of the fuel implosion. After that, all the data by the Lagrangian implosion code are converted to them for the Eulerian code. The fusion Deuterium (D)-Tritium (T) fuel and the inward moving heavy tamping material are imploded and deformed seriously at the stagnation phase. The Euler fluid code is appropriate to simulate the fusion fuel compression, ignition and burning. The Code O-SUKI 2D simulation system provides a capability to compute and to study the HIF target implosion dynamics.O-SUKI代码是一套集成化二维（2D）仿真程序系统，用于模拟重离子束（Heavy Ion Beam, HIB）惯性约束聚变（Inertial Confinement Fusion, HIF）场景下，直接驱动型核聚变靶丸的燃料内爆、点火与燃烧过程。该系统由四大模块构成：OK3的HIB辐照与能量沉积程序（发表于《Comput. Phys. Commun.》181卷，1332页，2010年）、拉格朗日流体（Lagrangian fluid）内爆程序、数据转换程序，以及欧拉流体（Euler fluid）内爆、点火与燃烧程序。OK3用于计算多束重离子束辐照球形燃料靶的过程：单束重离子束会被拆分为多个子束，每个重离子子束将根据粒子能量，沿自身轨迹在能量沉积层内完成能量沉积。此外，OK3还支持重离子束轴的摆动振荡功能，可获取燃料靶能量吸收体内部的HIB能量沉积空间细节分布。在燃料内爆的空泡闭合时刻之前，通过与OK3耦合的二维拉格朗日流体程序，可计算得到球形靶的二维内爆行为。在此之后，需将拉格朗日内爆程序生成的全部数据转换为适配欧拉程序的格式。在滞止阶段，聚变氘（Deuterium, D）-氚（Tritium, T）燃料以及向内运动的重质填充材料会发生剧烈的内爆变形。欧拉流体程序能够精准模拟聚变燃料的压缩、点火与燃烧过程。O-SUKI二维仿真系统具备计算与研究HIF靶内爆动力学过程的能力。