受地球固体内核的超转动启发，该研究小组探究了自由旋转物体与柱状容器内的Rayleigh–Bénard热对流的大尺度环流（LSC）之间的动力学相互作用。令人惊讶且持续的自转现象同时在自由物体和LSC中出现，破坏了系统的轴对称性。自转速度随着热对流的强度增加而单调增大，热对流的强度由Rayleigh数（Ra）来衡量，该数值与加热底部和冷却顶部之间的温差成正比。
旋转方向偶尔会自发地反转，特别是在较高的Ra下更为频繁。反转事件遵循泊松过程；流动波动可能会随机地中断和重新建立维持旋转的机制。这种自转仅由热对流驱动，并通过添加自由物体来增强，丰富了经典动力系统。
附：英文原文
Title: Persistent corotation of the large-scale flow of thermal convection and an immersed free body
Author: Wang, Kaizhe, Zhang, Jun
Issue&Volume: 2023-5-15
Abstract: Inspired by the superrotation of the Earth’s solid core, we investigate the dynamics of a free-rotating body as it interacts with the large-scale circulation (LSC) of the Rayleigh–Bénard thermal convection in a cylindrical container. A surprising and persistent corotation of both the free body and the LSC emerges, breaking the axial symmetry of the system. The corotational speed increases monotonically with the intensity of thermal convection, measured by the Rayleigh number Ra, which is proportional to the temperature difference between the heated bottom and cooled top. The rotational direction occasionally and spontaneously reverses, occurring more frequently at higher Ra. The reversal events follow a Poisson process; it is feasible that flow fluctuations randomly interrupt and reestablish the rotation-sustaining mechanism. This corotation is powered by thermal convection alone and promoted by the addition of a free body, enriching the classical dynamical system.
DOI: 10.1073/pnas.2217705120
Source: https://www.pnas.org/doi/10.1073/pnas.2217705120