Magnetic diffusion and the motion of field lines
Magnetic diffusion and the motion of field lines
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DOI：
10.1080/03091920500044808
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发表时间：
2005-04
影响因子：
1.3
通讯作者：
A. Wilmot-Smith;E. Priest;G. Hornig
中科院分区：
文献类型：
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作者：
A. Wilmot-Smith;E. Priest;G. Hornig
扩散的磁场通过等离子体中讨论的一维，二维和三维的配置，连同描述这种扩散的磁通量的速度，当它存在时，一般是非唯一的方面的可能性。物理上有用的定义，这样的速度包括这样做的能量流或在这样一种方式，它消失在一个稳定的状态。直线场线（或平面通量表面）扩散，就好像通量在中性片处消失，而圆形场线（或圆柱形通量表面）扩散，就好像通量在0型中性线处消失。在三维空间中，并不总是能够定义通量速度，例如当通过闭合场线的磁通量随时间变化时。然而，在至少某些这样的情况下，可以用一对准通量速度来描述磁场的行为。
Diffusion of a magnetic field through a plasma is discussed in one-, two- and three-dimensional configurations, together with the possibility of describing such diffusion in terms of a magnetic flux velocity, which, when it exists, is in general non-unique. Physically useful definitions of such a velocity include doing so in terms of the energy flow or in such a way that it vanishes in a steady state. Straight field lines (or plane flux surfaces) diffuse as if flux is disappearing at a neutral sheet, whereas circular field lines (or cylindrical flux surfaces) do so as if flux is disappearing at an 0-type neutral line. In three dimensions it is not always possible to define a flux velocity, for example when the magnetic flux through a closed field line is changing in time. However, in at least some such cases it is possible to describe the behaviour of the magnetic field in terms of a pair of quasi-flux-velocities.