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在磁动力等离子体中,非局部对流级联的贡献
J Friedrich1, M Wilbert2, R Marino3
1ForWind, Institute of Physics, University of Oldenburg, Küpkersweg 70, D-26129 Oldenburg, Germany.
Physical review. E
|May 17, 2024
概括
磁动力学 (MHD) 流中的非局部效应会影响能量传输. 考虑到这些非局部贡献,可以改进流能耗的模型,这对于理解太阳能风加热至关重要.
科学领域:
- 等离子体物理学的物理学
- 流体动力学 流体动力学
- 天体物理学 天体物理学
背景情况:
- 动荡的能量级联描述了在流体中跨的能量转移.
- 磁动力学 (MHD) 控制着等离子体,在等离子体中,磁场和流体运动相互作用.
- 了解MHD流中的能量消散是太阳风加热等天体物理现象的关键.
研究的目的:
- 调查MHD等离子体中乱能量级联的非局部贡献.
- 改进对跨尺度的动力和磁能转移的理解.
- 改进与空间等离子体物理学相关的能量消散模型.
主要方法:
- 从MHD方程中得出的Politano和Pouquet定律的复习.
- 引入一个新的术语来解释通过阿尔夫恩效应的非局部能量转移.
- 执行同质和同源的MHD流的直接数值模拟.
主要成果:
- 有证据表明,MHD的乱能量级联有着重要的非本地贡献.
- 证明忽视非本地术语可能会高估能量消耗率.
- 识别特定的等离子体配置,其中非局部效应是明显的.
结论:
- 非局部传输是MHD动荡能量级联的关键组成部分.
- 精确的太阳风加热模型需要结合这些非局部效应.
- 拟议的术语增强了MHD流模拟的预测能力.
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