论文标题
在Tokamaks中减轻干扰的颗粒消融的近场模拟
Near-field simulations of pellet ablation for disruptions mitigation in tokamaks
论文作者
论文摘要
已经进行了血浆减轻参数空间中单个霓虹灯的消融的详细数值研究。使用Frontier，一种具有显式跟踪材料接口的跟踪的流体动力和低磁性Reynolds编号MHD代码。 Frontier的物理模型解决了沉淀表面的消融，并形成了茂密的冷云材料，流经热等离子体电子的能量沉积，通过消融云的热等离子体电子，沿磁场线和辐射损失的消融云的扩展。基于SAHA方程的局部热力学平衡模型已用于解决云中的原子过程，并已使用Redlich-kwong校正到理想状态的状态气体方程，用于冷和密集的气体。边界颗粒代码是[R.中描述的下一代代码Samulyak，T。Lu，P。Parks，核融合，（47）2007，103--118]。在一维球面对称近似中的半分析改进的中性气体屏蔽模型已经验证了它。主要结果包括定量原子过程的影响和雷德里奇 - 夸纠正对球体对称近似中的颗粒消融的影响，并在广泛的颗粒和血浆参数中对分析缩放定律的验证。使用轴向对称的MHD模拟，已经研究了消融通道的特性以及在强度提高的磁场中的沉淀率的降低。虽然已将重点放在血浆减轻血浆中断的霓虹灯颗粒中，但还提出了氘加油颗粒的选定结果。
Detailed numerical studies of the ablation of a single neon pellet in the plasma disruption mitigation parameter space have been performed. Simulations were carried out using FronTier, a hydrodynamic and low magnetic Reynolds number MHD code with explicit tracking of material interfaces. FronTier's physics models resolve the pellet surface ablation and the formation of a dense, cold cloud of ablated material, the deposition of energy from hot plasma electrons passing through the ablation cloud, expansion of the ablation cloud along magnetic field lines and the radiation losses. A local thermodynamic equilibrium model based on Saha equations has been used to resolve atomic processes in the cloud and Redlich-Kwong corrections to the ideal gas equation of state for cold and dense gases have been used near the pellet surface. The FronTier pellet code is the next generation of the code described in [R. Samulyak, T. Lu, P. Parks, Nuclear Fusion, (47) 2007, 103--118]. It has been validated against the semi-analytic improved Neutral Gas Shielding model in the 1D spherically symmetric approximation. Main results include quantification of the influence of atomic processes and Redlich-Kwong corrections on the pellet ablation in spherically symmetric approximation and verification of analytic scaling laws in a broad range of pellet and plasma parameters. Using axially symmetric MHD simulations, properties of ablation channels and the reduction of pellet ablation rates in magnetic fields of increasing strength have been studied. While the main emphasis has been given to neon pellets for the plasma disruption mitigation, selected results on deuterium fueling pellets have also been presented.
