赤道东太平洋弯曲急流区质点轨迹及混沌运动机制

Study on Particles' Trajectory and Chaotic Motion in the Region of Meandering Jet in the Eastern Equatorial Pacific

利用运动学模型 ,研究了弯曲急流控制参数为定常和发生周期扰动时的流体质点运动轨迹以及混沌现象的产生机制。发现弯曲急流控制参数为定常时 ,流体质点的运动为规则的周期运动 ;而控制参数发生扰动时 ,可以发生流体质点在不同特征区的穿行 ,流体质点的运动具有混沌特性。弯曲急流的相速、振幅发生周期扰动均可使流体质点的运动出现混沌特性。作者从运动学上对弯曲急流区的漂流浮标混沌特性给出了解释。

The fluid particles' trajectories and kinetic mechanism of chaotic motion were studied with a kinetic model constructed by Meng Xiangfeng in 2001. Particles' trajectories in the two cases that the control parameters of the meandering jet were steady and changed periodically were studied. It was found that the fluid particles' motions were regular and periodic with steady control parameters of the meandering jet. While with periodic disturbance about the steady control parameters such as phase velocity and meandering amplitude, the fluid particles could traverse across the different characterization zone or show aperiodic behavior. The particles showed chaotic characteristics in motion. Therefore the disturbance of the phase velocity or meander amplitude could make the motion of the fluid particles chaotic. A preliminary kinetic explanation about the chaotic characteristics of the floating drifters was given in this paper.