Power dependence of the density limit due to plasma–wall interactions in a burning plasma

作者：Jiaxing Liu, Ping Zhu, D. F. Escande · 发表于：Plasma Physics and Controlled Fusion · 年份：2025 · DOI：10.1088/1361-6587/adf883 · 被引用次数：1 · 研究领域：Magnetic confinement fusion research、Plasma Diagnostics and Applications、Laser-induced spectroscopy and plasma

Abstract The density limit is one of the major obstacles to achieving the desired fusion performance in tokamaks. However, the underlying physics mechanism for its recently observed power dependence in experiments has not been well understood or predicted in theory. In this work, we derive the power-dependent scaling of the density limit from the plasma–wall self-organization (PWSO) theory [DF. Escande 2022 NF] for the first time. These newly derived scalings successfully match the experimentally observed power dependence of density limits in multiple tokamak devices, such as ASDEX-U and W7-AS, confirming the validity of the PWSO theory. Critically influencing factors are identified as plasma–wall sputtering and particle confinement time. In addition, the effects of nonsputtered impurities and fusion products are evaluated, and the refined PWSO-density limit model is extended to the burning plasma regime to predict the conditions necessary for entering the burning plasma.