Research on Influence of Metal-Vapor Deposition on Target Injected into a Laser Fusion Reactor

在未来的激光聚变反应堆中，液态金属将被用来保护第一层壁免受微爆炸成核的高能粒子的伤害。反应器将充满低压金属蒸汽，用于加热低温目标。从理论上和实验上研究了金属蒸气对靶材的影响。建立了一种评估金属蒸气在注入低温靶上沉积速率的模型。讨论了沉积金属气相的厚度和均匀性，比较了均匀性的要求。讨论的结果是蒸汽压力和喷射速度的设计空间。由于沉积金属层厚度的不均匀性，注射时反应器内的蒸汽压必须小于0.05托。讨论了汽流对注入目标轨迹的影响。制备了检测沉积速率和分布的实验装置。对空中靶标进行了初步的喷射实验，记录了40m/s的喷射速度。为了模拟反应器环境，制备了电炉。炉的记录温度为1100C，足以达到反应器中所需的蒸汽压。注射实验正在进行中。

In a future laser fusion reactor, liquid metal will be used to protect the first wall from energetic particles nucleated by micro-explosions. The reactor will be filled with low pressure metal vapor that heat the cryogenic target. The influence of metal vapor on target is studied theoretically and experimentally.A model to evaluate the deposition rate of metal vapor on the injected cryogenic target is nucleated. The thickness and the uniformity of the deposited metal vapor is discussed comparing requirement for the uniformity. The discussion resulted in a design space for the vapor pressure and the injection velocity. The vapor pressure in the reactor at the time of the injection must be less than 0.05 Torr due to the non-uniformity of the thickness of the deposited metal layer. Influence of the vapor flow on the trajectory of injected target is also discussed.Experimental equipment to check the deposition rate and the distribution was prepared. Preliminary experiment on injection of a target in the air was conducted and the injection velocity of 40m/s was recorded. To simulate the reactor environment, an electric furnace was prepared. The recorded temperature of the furnace was 1100C that is sufficient to achiever the required vapor pressure in the reactor. The injection experiment is now in progress.