Computer studies on powerful magnetic energy conversion by the spontaneous fast reconnection mechanism
Computer studies on powerful magnetic energy conversion by the spontaneous fast reconnection mechanism
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DOI：
10.1063/1.870965
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发表时间：
1995-02
影响因子：
2.2
通讯作者：
M. Ugai
中科院分区：
文献类型：
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作者：
M. Ugai
在自发重联模型的基础上，计算机模拟研究了最初存储在电流片系统中的磁能释放成等离子体能量的物理机制。对于均匀电阻率模型，随着扩散区随时间的延长，最终建立了Sweet-Parker机制。扩散区中的欧姆加热ηJ2在释放磁能中起主导作用。附着在扩散区域上，会形成一个长的等离子体团，并像大振幅阿尔文脉冲一样传播，其中发电机和电机效应沿着等离子体团边界被抵消。对于异常电阻率模型，快速重联机制最终成立的扩散区仍然是本地化的X中性点附近。正是沿着沿着慢激波层的强大的电动机效应[u 0]，急剧地释放了储存的磁能。一个大规模的等离子体团会明显膨胀，所以周围的磁场
On the basis of the spontaneous reconnection model, computer simulations study the physical mechanism by which magnetic energy, initially stored in a current sheet system, is released into plasma energies. For the uniform resistivity model, the Sweet–Parker mechanism is eventually set up with the diffusion region becoming longer with time. It is the Ohmic heating ηJ2 in the diffusion region that plays the dominant role in releasing the magnetic energy. Attached to the diffusion region, a long plasmoid is formed and propagates like a large‐amplitude Alfven pulse, where the generator and motor effects are canceled along the plasmoid boundary. For the anomalous resistivity model, the fast reconnection mechanism is eventually set up with the diffusion region remaining to be localized near an X neutral point. It is the powerful motor effect [u⋅(J×B)≳0] along the slow shock layers that drastically releases the stored magnetic energy. A large‐scale plasmoid distinctly swells, so that the ambient magnetic fields ...