Analytic characterization of sub-Alfvénic turbulence energetics
Analytic characterization of sub-Alfvénic turbulence energetics
复制标题
亚阿尔弗尼湍流能量学的分析表征
DOI：
10.1051/0004-6361/202346072
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发表时间：
2023
影响因子：
6.5
通讯作者：
Pavlidou, V.
中科院分区：
文献类型：
--
作者：
Skalidis, R.;Tassis, K.;Pavlidou, V.
磁流体动力学 (MHD) 湍流是与许多系统相关的跨领域过程。理解这些系统的先决条件是限制 MHD 湍流的作用，特别是动能和磁力形式之间的能量交换。迄今为止，强磁化和可压缩湍流的能量学一直阻碍着理解它们的尝试。数值模拟表明，动能比脉动磁能高几个数量级。我们通过计算基于相干圆柱形流体团动力学的可压缩和亚阿尔芬湍流的能量学来解决这个缺乏平衡的难题。使用 MHD 拉格朗日，我们分析证明，大部分磁能转化为动能，是储存在有序磁场和脉动磁场之间耦合中的能量。分析关系与数值数据（直至二阶项）惊人地一致。
Magnetohydrodynamic (MHD) turbulence is a cross-field process relevant to many systems. A prerequisite for understanding these systems is to constrain the role of MHD turbulence, and in particular, the energy exchange between kinetic and magnetic forms. The energetics of strongly magnetized and compressible turbulence has so far resisted attempts to understand them. Numerical simulations reveal that kinetic energy can be orders of magnitude higher than fluctuating magnetic energy. We solved this lack-of-balance puzzle by calculating the energetics of compressible and sub-Alfvénic turbulence based on the dynamics of coherent cylindrical fluid parcels. Using the MHD Lagrangian, we proved analytically that the bulk of the magnetic energy transferred to kinetic energy is the energy that is stored in the coupling between the ordered and fluctuating magnetic field. The analytical relations are in strikingly good agreement with numerical data, up to second-order terms.