论文标题
东H模式等离子体和ITER 15 MA基线场景的刮擦层功率宽度的模拟。
Simulations of scrape-off layer power width for EAST H-mode plasma and ITER 15 MA baseline scenario by 2D electrostatic turbulence code
论文作者
论文摘要
刮擦层功率宽度（λ_Q）是表征分离热载荷的重要参数。近年来，已经进行了许多实验，理论和数值研究。在本文中，已升级的2D静电湍流代码BOUT-HESEL首次升级以模拟H模式等离子体。该代码已针对先前的实现和实验进行了验证。发现模拟的λ_Q与东H模式放电的EICH缩放率很好。该代码用于模拟ITER 15MA基线方案。 ITER模拟表明，径向粒子/热传输以斑点传输为主，并预测λ_{q，iter} = 9.6 mm，这比EICH缩放的预测大得多。根据东部修改的情况，提出了提出的估计的HESEL H模式缩放，λ_Q= 0.51R_C^1.1B_T^（ - 0.3）Q_95^1.1。此缩放预测λ_{q，iter} = 9.3毫米，对于ITER情况而言，它非常吻合。进一步的研究结合了EICH缩放数据库中的基本参数，表明，EICH缩放中对机器尺寸（RC）的缺失缩放率似乎是由于当前设备对环形磁场（BT）的负尺度依赖性所遮盖的。然而，迭代并非如此，解释了为什么在最近的研究和本文中的模拟可以重现当前设备的EICH缩放，而是预测ITER的λ_Q更大的λ_Q。根据仿真结果，λ_Q对RC的强正缩放依赖性是由于在增加机器大小时增加了平行连接长度和径向EXB湍流热传输的增强而减慢平行热传输的组合。
The scrape-off layer power width (λ_q) is an important parameter for characterizing the divertor heat loads. Many experimental, theoretical, and numerical studies have been performed in recent years. In this paper, a 2D electrostatic turbulence code, BOUT-HESEL, has been upgraded to simulate H-mode plasmas for the first time. The code is validated against the previous implementation and the experiments. The simulated λ_q is found to agree quite well with the Eich scaling for the EAST H-mode discharge. The code is utilized to simulate the ITER 15MA baseline scenario. The ITER simulation reveals that the radial particle/heat transports are dominated by blobby transports, and predicts λ_{q,ITER} = 9.6 mm, which is much larger than the prediction by the Eich scaling. Based on the EAST modified cases, an estimated HESEL H-mode scaling, λ_q=0.51R_c^1.1B_t^(-0.3)q_95^1.1 is proposed. This scaling predicts λ_{q,ITER} = 9.3 mm, which agrees surprisingly well with that for the ITER case. A further investigation combined with the basic parameters in the database of the Eich scaling shows that the missing positive scaling dependence on the machine size (Rc) in the Eich scaling appears to be shaded by the negative scaling dependence on the toroidal magnetic field (Bt) for current devices. This is however not the case for ITER, explaining why simulations in recent studies and in this paper can reproduce the Eich scaling for current devices, but predict a much larger λ_q for ITER. According to the simulation results, the strong positive scaling dependence of λ_q on Rc is due to a combination of slowing down the parallel heat transports by increasing the parallel connection length and the enhancement of the radial ExB turbulent heat transports when the machine size is increased.
