无力磁场和Beltrami流

On Force-Free Magnetic Fields and Beltrami Flows

National Laboratory for Turblence Research, Department of Mechanics and Engineering Science Peking Unversity Beijing 100871, P. R. China

摘要: 场矢量处处平行其旋度的管式矢量场具有复杂的拓扑结构．而且通常表现出混饨行为．本文提供了具有常数比例因子的这类矢量场在三种基本坐标系内的解析解,并指出完全导电流体内的一个Beltrami流能维持一个定常无力磁场,如果磁场矢量处处平行速度．
- 解析解 /
- 最大螺旋度 /
- 混沌磁力线
Abstract: Solenoidal vector fields,which satisfy the condition that the field vector every where parallels to its curl,have complex topologicla structures,andusually show chaotic behaviors.In this paper,analytical solutions for vector fields with constant proportional facfor in three basic coordinate sysems are presented and it is pointed out that a Beltrami flow can sustain a steady force-free magnetic fild in a perfectly conducting fluid,provided the magnetic field is parallel to the velocity everywhere.
- analytical solutions /
- maximal helicity /
- chaotic lines of force

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