Double shell capsule implosions are an alternative approach to achieving alpha heating on the National Ignition Facility. Current machining techniques construct the outer shell as two hemispheres that are glued together, and the deuterium and tritium (DT) liquid inside the inner shell will be injected by a fill tube. These features introduce asymmetries and jetting that may disrupt the confinement of the DT fuel if not carefully controlled. Simulations indicate that in order to achieve high yields in the laboratory, these features as well as susceptibility to the Rayleigh–Taylor instability (RTI) must be mitigated. Due to uncertainties in computational models and the expense of using the best physics models at adequate resolution in three dimensions, our computational modeling must be constrained by experiments. We report on the results of recent hydrogrowth radiography and dual-axis keyhole experiments with double shell targets that have been used to evaluate our modeling of the outer shell joint as well as the impacts of high-energy x-ray preheat that strongly impacts RTI growth. Our simulations show good agreement with the experimental data and inform several important modeling choices.

中文翻译：

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使用实验约束间接驱动双壳胶囊内爆的计算模型

双层胶囊内爆是在国家点火设施上实现α加热的另一种方法。当前的机械加工技术将外壳构造为两个半球，这些半球被粘合在一起，并且内壳内部的氘和tri（DT）液体将通过填充管注入。这些特征导致不对称和喷射，如果不仔细控制，可能会破坏DT燃料的限制。模拟表明，为了在实验室中获得高产量，必须减轻这些特征以及对瑞利泰勒不稳定性（RTI）的敏感性。由于计算模型的不确定性以及在三个维度上以足够的分辨率使用最佳物理模型的花费，我们的计算模型必须受到实验的限制。我们报告了最近的水电子照相和双壳双轴匙孔实验的结果，这些实验已用于评估我们对外壳关节的建模以及高能X射线预热的影响，这些影响强烈影响RTI的生长。我们的仿真结果与实验数据吻合良好，并为一些重要的建模选择提供了依据。