Quasigeostrophic Ellipsoidal Vortex Model
Quasigeostrophic Ellipsoidal Vortex Model
复制标题
准地转椭球涡模型
DOI：
10.1143/jpsj.70.1942
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发表时间：
2001
影响因子：
1.7
通讯作者：
N. Takahashi
中科院分区：
文献类型：
--
作者：
T. Miyazaki;Yutaro Furuichi;N. Takahashi
为了研究准等转湍流中涡旋相互作用的动力学，建立了椭球涡旋模型。每个相干涡旋用均匀位涡椭球来模拟。假设每个涡旋在其他涡旋引起的应变场影响下主轴和倾角发生变化，但仍然是椭球体。椭球涡旋的动力学是从描述准等转涡旋动力学的偏微分方程中提取出来的有限自由度哈密顿系统。除了系统的总能量和卡西米尔数（如涡高和涡体积）守恒外，涡度中心和角动量守恒。即使在两体系统中也可以观察到混沌运动。
An ellipsoidal vortex model is developed in order to investigate the dynamics of vortex interactions in a quasigeostrophic turbulence. Each coherent vortex is modeled by an ellipsoid of uniform potential vorticity. It is assumed that each vortex remains to be an ellipsoid, although its principal axes and inclination angles change under the influence of the strain field induced by other vortices. The dynamics of ellipsoidal vortices are shown to be a Hamiltonian system of finite degree of freedom extracted from the partial differential equations that describe quasigeostrophic vortex dynamics. The center of vorticity and the angular momentum are conserved, besides the total energy and Casimirs of the system, such as the vortex height and the vortex volume. Chaotic motions are observed even in a two-body system.