Formation of Burgers Vortex and its Dynamics in Magnetized Plasmas

1.得到了与轴对称系统中观测到的类台风涡旋相一致的定态解，并给出了类台风涡旋背后的物理机制.如果包括离心力，则E x B漂移有两个分支。一个是众所周知的普通E x B漂移，它由洛伦兹力和势力的平衡决定。新认识的一种是由洛伦兹力和离心力实现的反常E x B漂移。由于反常E x B力与径向坐标成正比，且在无穷远处发散，通常可忽略此分支。而在类似台风的涡旋中，涡旋的核心部分则可以用异常的E x B漂移来解释。旋涡的外部由普通的E x B漂移描述。因此，首先将异常E x B漂移识别为物理过程.从力的平衡来看，密度结构由离心力决定。中心处的密度较低，并向旋涡边缘增加。因此等离子体在中心有一个洞。与密度结构相对应，径向流向中心收敛，转化为轴向流.涡核区的轴向流动方向为上游，涡外的轴向流动方向为下游，表明涡核区的轴向流动具有多胞结构的特征。然而，这一点尚未得到充分理解。势在中心处最大，并向旋涡边缘减小。最大方位速度为1.5倍离子声速，最大径向速度为0.5倍离子声速。因此，向内的离子速度是超音速的，并且满足玻姆条件以产生空气中鞘层。这件事还没有解决。

1. A stationary solution has been obtained which shows a good agreement with the observed typhoon-like vortex in axi-symmetric system and physics behind the typhoon-like vortex has been given.2. There are two branches for the E x B drift if a centrifugal force is included. One is well known ordinary E x B drift which is determined by a balance of the Lorenz force and the potential force. Newly recognized one is an anomalous E x B drift which is realized by the Lorenz force and the centrifugal force. Since the anomalous E x B force is proportional to radial coordinate and diverges at infinity, usually this branch can be ignored. However in a typhoon like vortex, the core part of the vortex is explained by the anomalous E x B drift. Outer part of the vortex is described by an ordinary E x B drift. Thus an anomalous E x B drift is first to be identified as a physical process.3. From the force balance, the density structure is determined by the centrifugal force. The density is low at the center and increases toward the edge of the vortex. Thus the plasma has a hole at the center.4. Corresponding to the density structure the radial flow converges towards the center which is converted into an axial flow.5. The axial flow in the core part of the vortex is directed toward up-stream while the axial flow outside the vortex is directed to down-stream, which suggests the axial flow is characterized by a multiple cell structure. However this has not been fully understood.6. The potential is maximum at the center and decreases towards the edge of the vortex. The maximum of the azimuthal velocity is 1.5 times the ion sound velocity and the radial velocity is 0.5 times the ion sound velocity. Therefore the inward ion velocity is super-sonic and satisfies the Bohm condition to create a mid-air sheath. This is left unsolved.