Resonant magnetohydrodynamic waves in high-beta plasmas
Resonant magnetohydrodynamic waves in high-beta plasmas
复制标题
高β等离子体中的共振磁流体动力波
DOI：
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发表时间：
2009
期刊：
影响因子：
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通讯作者：
M. Ruderman
中科院分区：
文献类型：
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作者：
M. Ruderman
当整体磁流体力学（MHD）波在弱耗散非均匀等离子体中传播时，该波与局域Alfven波或慢MHD波的共振相互作用是可能的。这种相互作用发生在共振位置，在该位置，全球波的相速度与阿尔文波或慢MHD波的相速度一致。作为这种相互作用的结果，形成了包围谐振位置的耗散层，其厚度与R−1/3成比例，其中R <$1是雷诺数。共振层中的波动的特征在于大振幅和大梯度。大梯度的存在下，即使在非常弱的耗散等离子体的全球波的强烈耗散。通常，全球波动的特点是同时存在阿尔文和慢共振。在具有小或中等等离子体β β的等离子体中，Alfven共振和慢共振对应的共振位置被很好地分离，从而使等离子体中的波动被分离。
When a global magnetohydrodynamic (MHD) wave propagates in a weakly dissipative inhomogeneous plasma, the resonant interaction of this wave with either local Alfven or slow MHD waves is possible. This interaction occurs at the resonant position where the phase velocity of the global wave coincides with the phase velocity of either Alfven or slow MHD waves. As a result of this interaction a dissipative layer embracing the resonant position is formed, its thickness being proportional to R−1/3, where R⪢1 is the Reynolds number. The wave motion in the resonant layer is characterized by large amplitudes and large gradients. The presence of large gradients causes strong dissipation of the global wave even in very weakly dissipative plasmas. Very often the global wave motion is characterized by the presence of both Alfven and slow resonances. In plasmas with small or moderate plasma beta β, the resonance positions corresponding to the Alfven and slow resonances are well separated, so that the wave motion in the ...