Three-dimensional structure of radiative cooling in impurity seeded plasmas in the Large Helical Device
Three-dimensional structure of radiative cooling in impurity seeded plasmas in the Large Helical Device
复制标题
大型螺旋装置中杂质种子等离子体辐射冷却的三维结构
DOI：
10.1016/j.nme.2022.101294
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发表时间：
2022
影响因子：
2.6
通讯作者：
Munechika K.
中科院分区：
文献类型：
--
作者：
Mukai K.;Kawamura G.;Masuzaki S.;Hayashi Y.;Tanaka H.;Peterson B.J.;Oishi T.;Suzuki C.;Kobayashi M.;Munechika K.
在偏滤器分离过程中，由于注入氮气（N2）而引起的辐射冷却在三维空间中的局部化现象被实验探测到。由于沿沿着某些磁力线的局部化导致偏滤器板热负荷降低的环向不对称性，因此对于聚变堆应避免这种情况。三维局部结构提取使用主成分分析（PCA）从二维辐射图像测量与红外成像视频测辐射热计（IRVB）。通过应用PCA的34个图像中的每一个在N2种子等离子体与环对称的热负荷减少和氖（Ne）种子等离子体与环对称的热负荷减少，N2种子等离子体的辐射特征被发现作为主成分（PC）之一。三维输运程序EMC 3-EIRENE表明，由于第一电离能的差异，在偏滤器腿之一的电离增强氮气播种相比，氖播种。来自偏滤器腿的磁场线沿着提取的辐射结构，并终止于偏滤器，其中热负荷由于N2播种而降低。这些结果表明，三维局部结构的辐射冷却实验检测。
Three-dimensionally localization of radiative cooling due to nitrogen (N2) seeding for divertor detachment was detected experimentally. Since the localization along some magnetic field lines induces toroidal asymmetry of heat load reduction on divertor plates, it should be avoided for fusion reactors. The three-dimensionally localized structure was extracted using Principal Component Analysis (PCA) from two-dimensional radiation images measured with an InfraRed imaging Video Bolometer (IRVB). By applying PCA to 34 images each in N2seeded plasmas with toroidally-asymmetric heat load reduction and in neon (Ne) seeded plasmas with toroidally-symmetric heat load reduction, a radiation feature in N2seeded plasmas was found as one of the principal components (PC). The three-dimensional transport code EMC3-EIRENE indicated that the ionization in one of the divertor legs is enhanced in nitrogen seeding compared with Ne seeding due to the difference in the first ionization energy. The magnetic field lines from the divertor leg were along the extracted radiation structure and were terminated by the divertor where the heat load decreased due to the N2seeding. These results indicate that three-dimensionally localized structure of radiative cooling was detected experimentally.