Phasespace transport of a quasi-neutral multi-fluid plasma over the solar wind MHD termination shock
Phasespace transport of a quasi-neutral multi-fluid plasma over the solar wind MHD termination shock
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太阳风 MHD 终止激波上准中性多流体等离子体的相空间输运
DOI：
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发表时间：
2012
期刊：
影响因子：
--
通讯作者：
I. Chashei
中科院分区：
文献类型：
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作者：
H. Fahr;M. Siewert;I. Chashei
我们研究了多离子MHD冲击的物理特性，即当混合离子群的超音速流被迫适应更下游的压力障碍时形成的MHD冲击特征。我们将描述这种情况，通过使用一个多流体的方法为不同的特定质量和电荷的离子种群的混合物，每个离子物种。首先，我们计算的有效电势，迫使等离子体体减速到下游的整体流速，然后也定义了该系统的下游磁场被冻结。然后，我们计算不可避免的离子特定的过冲速度和增益，要求能量守恒，离子特定的贡献下游的热能和压力。因此，目的是找到等离子体混合物的下游流的MHD状态的解决方案，特别是质子-电子等离子体。我们推导出一个隐式方程的有效压缩比和明确的关系，不同的，下游的离子和电子的温度作为多流体压缩比的函数。通过将所有下游部分压力相加并将其与上游冲压压力进行比较，得到实际的多流体压缩比seff。正如我们所示，电子压力是下游等离子体总压力的主要贡献。
We study the physics of a multi-ion MHD shock, i.e. an MHD shock feature that forms when a supersonic flow of mixed ion populations is forced to adapt itself to a pressure obstacle further downstream. We shall describe this situation by using a multi-fluid approach for a mixture of ion populations with different specific masses and charges per ion species. First we calculate the effective electric potential that forces the plasma bulk to decelerate to the downstream bulk flow velocity which also then defines that system into which the downstream magnetic field is frozen-in. Then we calculate the unavoidable ion-specific overshoot velocities and gain from them, requesting energy conservation, the ion-specific contributions to the downstream thermal energies and pressures. The aim thereby is to find the solution for the MHD status of the downstream flow of the plasma mixture, specifically for a proton-electron plasma. We derive an implicit equation for the effective compression ratio and explicit relations for the different, downstream ion and electron temperatures as function of the multi-fluid compression ratio s. The resulting actual multi-fluid compression ratio seff is found by adding up all the partial downstream pressures and comparing it with the upstream ram pressure. As we can show, the electron pressure is the dominant contribution to the total downstream plasma pressure.
影响因子：
6.5
作者：
H. Fahr;M. Siewert
通讯作者：
H. Fahr;M. Siewert