等离子体湍流能量传输的尺度相关性  

Energy Transfer in Plasma Turbulence:From Macro to Micro Scales

作　　者：杨艳 万敏平 Valentini Francesco Matthaeus William H 史一蓬[4] 陈十一 YANG Yan;WAN Min-ping;VALENTINI Francesco;MATTHAEUS William H;SHI Yi-peng;CHEN Shi-yi(Southern University of Science and Technology, Shenzhen 518055, China;Dipartimento di Fisica, Università della Calabria, I-87036 Cosenza, Italy;Department of Physics and Astronomy, University of Delaware, Newark DE 19716, USA;Peking University, Beijing 100871, China)

机构地区：[1]南方科技大学,广东深圳518055 [2]卡拉布里亚大学物理系,意大利科森扎87036 [3]特拉华大学物理与天文系,美国特拉华州纽瓦克19716 [4]北京大学,北京100871

出　　处：《气体物理》2021年第2期19-27,共9页Physics of Gases

基　　金：国家自然科学基金(11902138,91752201,11672123);南方科技大学校长卓越博士后基金。

摘　　要：对于空间环境中近乎无碰撞的等离子体,可采用Vlasov方程进行理论描述,基于Vlasov方程,讨论了等离子体湍流能量传输和耗散的过程由亚格子应力引起的尺度间的能量传输,电场做功,压强张量做功(压强张量与速度梯度张量的相互作用).通过混合Vlasov-Maxwell(HVM)数值模拟,进一步研究了能量传输通道之间的联系与区别.不同能量传输通道尽管在不同尺度起主要作用,但其空间的分布非常相似,即各能量传输通道之间存在一定的空间相关.结合近年数值模拟和卫星观测的结果,可以大致概括等离子体湍流从磁流体动力学(magnetohydrodynamic,MHD)尺度到动理学尺度的能量传输过程.For a weakly collisional or collisionless plasma,the Vlasov-Maxwell equation is an appropriate limit.The problems of energy transfer and dissipation in plasmas are addressed within the framework of the Vlasov approximation and,in particular there are essentially basic points which are cross-scale energy transfer flux due to subgrid-scale stress,the work done by electric field on charged particles,and the pressure tensor work(pressure-strain interaction).The associations and differences that exist among these energy transfer and dissipation surrogates were investigated in detail through hybrid Vlasov-Maxwell(HVM)simulation.They are found to be dominant at different scales,and are spatially located in proximity to each other even if their point-wise correlation may be weak.These results,in conjunction with previous studies based on numerical simulations and observations,provide a way to clarify the key steps of energy transfer from macroscopic magnetohydrodynamic(MHD)scales to kinetic scales.

关 键 词：能量传输 无碰撞等离子体 湍流 压强张量做功 电场做功 

分 类 号：O533[理学—等离子体物理] O361.3[理学—物理]