Theory-based scaling laws of the near and far scrape-off layer (SOL) widths are analytically derived for L-mode diverted tokamak discharges by using a two-fluid model. The near SOL pressure and density decay lengths are obtained by leveraging a balance among the power source, perpendicular turbulent transport across the separatrix, and parallel losses at the vessel wall, while the far SOL pressure and density decay lengths are derived by using a model of intermittent transport mediated by filaments. The analytical estimates of the pressure decay length in the near SOL is then compared to the results of three-dimensional, flux-driven, global, two-fluid turbulence simulations of L-mode diverted tokamak plasmas, and validated against experimental measurements taken from an experimental multi-machine database of divertor heat flux profiles, showing in both cases a very good agreement. Analogously, the theoretical scaling law for the pressure decay length in the far SOL is compared to simulation results and to experimental measurements in TCV L-mode discharges, pointing out the need of a large multi-machine database for the far SOL decay lengths.

通过使用双流体模型，针对 L 模式转向托卡马克放电，分析导出了基于理论的近和远刮削层 (SOL) 宽度的标度定律。近 SOL 压力和密度衰减长度是通过利用能量源、穿过分离面的垂直湍流输运和容器壁的平行损失之间的平衡获得的，而远 SOL 压力和密度衰减长度是通过使用以下模型得出的由细丝介导的间歇运输。然后将近 SOL 中压力衰减长度的分析估计值与 L 型转向托卡马克等离子体的三维、通量驱动、全局、两流体湍流模拟的结果进行比较，并根据来自偏滤器热通量分布的实验性多机数据库，在这两种情况下都显示出非常好的一致性。类似地，将远 SOL 中压力衰减长度的理论标度定律与模拟结果和 TCV L 模式放电的实验测量值进行比较，指出远 SOL 衰减长度需要大型多机数据库。