Viscous effects on plasmoid formation from nonlinear resistive tearing growth in a Harris sheet  

作　　者：Nisar AHMAD Ping ZHU Ahmad ALI Shiyong ZENG Nisar AHMAD;朱平;Ahmad ALI;曾市勇(CAS Key Laboratory of Geospace Environment and Department of Engineering and Applied Physics,University of Science and Technology of China,Hefei 230026,People's Republic of China;International Joint Research Laboratory of Magnetic Confinement Fusion and Plasma Physics,State Key Laboratory of Advanced Electromagnetic Engineering and Technology,School of Electrical and Electronic Engineering,Huazhong University of Science and Technology,Wuhan 430074,People's Republic of China;Department of Engineering Physics,University of Wisconsin-Madison,Madison,Wisconsin 53706,United States of America;Pakistan Tokamak Plasma Research Institute,Islamabad 44000,Pakistan;Department of Plasma Physics and Fusion Engineering,University of Science and Technology of China,Hefei 230026,People’s Republic of China)

机构地区：[1]CAS Key Laboratory of Geospace Environment and Department of Engineering and Applied Physics,University of Science and Technology of China,Hefei 230026,People's Republic of China [2]International Joint Research Laboratory of Magnetic Confinement Fusion and Plasma Physics,State Key Laboratory of Advanced Electromagnetic Engineering and Technology,School of Electrical and Electronic Engineering,Huazhong University of Science and Technology,Wuhan 430074,People's Republic of China [3]Department of Engineering Physics,University of Wisconsin-Madison,Madison,Wisconsin 53706,United States of America [4]Pakistan Tokamak Plasma Research Institute,Islamabad 44000,Pakistan [5]Department of Plasma Physics and Fusion Engineering,University of Science and Technology of China,Hefei 230026,People’s Republic of China

出　　处：《Plasma Science and Technology》2022年第1期18-29,共12页等离子体科学和技术（英文版）

基　　金：supported by the National Magnetic Confinement Fusion Science Program of China(No.2019YFE03050004);National Natural Science Foundation of China(Nos.11775221 and 51821005);U.S.DOE(Nos.DE-FG02-86ER53218 and DESC0018001);the Fundamental Research Funds for the Central Universities at Huazhong University of Science and Technology(No.2019kfyXJJS193);the support from NIMROD team;the support from the Chinese Government Scholarship。

摘　　要：In this work,the evolution of a highly unstable m=1 resistive tearing mode,leading to plasmoid formation in a Harris sheet,is studied in the framework of full MHD model using the Non-Ideal Magnetohydrodynamics with Rotation,Open Discussion simulation.Following the initial nonlinear growth of the primary m=1 island,the X-point develops into a secondary elongated current sheet that eventually breaks into plasmoids.Two distinctive viscous regimes are found for the plasmoid formation and saturation.In the low viscosity regime(i.e.P_(r)■1),the plasmoid width increases sharply with viscosity,whereas in the viscosity dominant regime(i.e.P_(r)■1),the plasmoid size gradually decreases with viscosity.Such a finding quantifies the role of viscosity in modulating the plasmoid formation process through its effects on the plasma flow and the reconnection itself.

关 键 词：VISCOSITY RECONNECTION PLASMOIDS Prandtl number 

分 类 号：O53[理学—等离子体物理]