Toward modeling of the scrape-off layer currents induced by electrode biasing using 2D particle-in-cell simulations  

作　　者：Huaxiang ZHANG Dehui LI Yunfeng LIANG 张华祥;李德徽;梁云峰(Institute of Plasma Physics,Chinese Academy o f Sciences,Hefei 230031,People's Republic of China;University of Science and Technology of China,Hefei 230026,People's Republic of China;Forschungszentrum Jülich GmbH.Institut für Energie und Klimaforschung Plasmaphysik.Trilateral Euregio Cluster,D-52425 Jiilich,Germany)

机构地区：[1]Institute of Plasma Physics,Chinese Academy o f Sciences,Hefei 230031,People's Republic of China [2]University of Science and Technology of China,Hefei 230026,People's Republic of China [3]Forschungszentrum Jiilich GmbH.Institut fiir Energie und Klimaforschung Plasmaphysik.Trilateral Euregio Cluster,D-52425 Jiilich,Germany

出　　处：《Plasma Science and Technology》2020年第10期62-75,共14页等离子体科学和技术（英文版）

基　　金：supported by National Natural Science Foundation of China (Nos. 51828101 and No.11875294);the National Key R&D Program of China (No. 2017YFE0301100)。

摘　　要：The property of scrape-off layer(SOL) currents induced by a biased electrode is investigated by fully kinetic collisionless two-dimensional particle-in-cell(PIC) simulations. A reduced Vlasov–Darwin model is employed, which is capable of describing the low-frequency kinetic behavior without electromagnetic vacuum modes(w^2=w_(pe)~2+ c^2k^2). A linear decay distribution of electron currents parallel to the background magnetic field is exhibited. Simulation analyses indicate that the cross field ion current is a key factor in sheath formation and global current balance. The influences of electrode area, biasing voltage and plasma source on the SOL current profile are studied, respectively.Characteristic plasma parameters in the far SOL region of the EAST tokamak are used in simulations to assess the current driving ability of the electrode biasing method. Due to the limitations of computational power, the geometrical size of the simulation domain is significantly smaller than the realistic SOL, which may lead to an absence of the quasi-neutral region in the upstream plasma.At last, a heuristic method is proposed to calculate the upper bound of the total current strength.

关 键 词：scrape-off layer electrode biasing PARTICLE-IN-CELL 

分 类 号：TL631.24[核科学技术—核技术及应用]