Modeling of the turbulent magnetohydrodynamic residual-energy equation using a statistical theory
Modeling of the turbulent magnetohydrodynamic residual-energy equation using a statistical theory
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DOI：
10.1063/1.2209232
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发表时间：
2006-06
影响因子：
2.2
通讯作者：
N. Yokoi
中科院分区：
文献类型：
--
作者：
N. Yokoi
在磁流体力学的框架下，研究了导电流体中动能和磁能之间的差异。平均分配偏差用湍流剩余能KR来衡量。借助于非均匀湍流的统计分析理论--双尺度直接相互作用近似，导出了在剩余能量演化方程中出现的相关张量的表达式。利用这些结果，我们提出了一个模型方程KR演变。该方程的结构的检查表明，缩放的剩余能量的演变与耦合的平均场剪切湍流的交叉螺旋度（速度-磁场相关性）。太阳风的应用表明，缩放的OKKR的OKKR可以增加附近的外部的阿尔芬点在内日光层，而几乎稳定的行为OKKR的OKKR的OKKR的建议在外日光层。这些结果与观测结果一致。
The difference between the kinetic and magnetic energies in a conducting fluid is investigated in the framework of magnetohydrodynamics. The deviation from equipartition is measured by the turbulent residual energy KR. With the aid of the two-scale direct-interaction approximation, a statistical analytical theory for inhomogeneous turbulence, expressions for the correlation tensors appearing in the evolution equation for the residual energy are derived. Using these results, we propose a model equation for KR evolution. Examination of the structure of this equation shows that the evolution of the scaled residual energy is related to the cross helicity (velocity-magnetic-field correlation) of turbulence coupled with the mean-field shears. An application to the solar wind shows that the scaled ∣KR∣ can be increased near the outside of the Alfven point in the inner heliosphere whereas the almost stationary behavior of ∣KR∣ is suggested in the outer heliosphere. These results are consistent with observations o...