论文标题
弱磁性球形卷轴流中的混沌波动力学
Chaotic wave dynamics in weakly magnetised spherical Couette flows
论文作者
论文摘要
提出了填充两个同心球之间间隙的液态金属的直接数值模拟。该流程受内部球体旋转（由雷诺数RE衡量）与弱外部施加的轴向磁场（由Hartmann数字HA测量）之间的相互作用。通过改变后者，从空间对称性和时间依赖性方面，可以获得丰富的流量特征。 HOPF分叉的结果发现了具有两个或三个独立频率的流动。它们在足够大的Hartmann数字间隔内保持稳定，其中检测到两，三，甚至四种类型的不同流动的多稳定性区域。通过准确的频率分析和庞加莱部分分析溶液的时间特征。还描述了经历了一个不稳定的流量分支，这也是三频解决方案的两倍级联和频率锁定的频率锁定。
Direct numerical simulations of a liquid metal filling the gap between two concentric spheres are presented. The flow is governed by the interplay between the rotation of the inner sphere (measured by the Reynolds number Re) and a weak externally applied axial magnetic field (measured by the Hartmann number Ha). By varying the latter a rich variety of flow features, both in terms of spatial symmetry and temporal dependence, is obtained. Flows with two or three independent frequencies describing their time evolution are found as a result of Hopf bifurcations. They are stable on a sufficiently large interval of Hartmann numbers where regions of multistability of two, three and even four types of these different flows are detected. The temporal character of the solutions is analysed by means of an accurate frequency analysis and Poincaré sections. An unstable branch of flows undergoing a period doubling cascade and frequency locking of three-frequency solutions is described as well.
