逆转捩过程中混沌特征的实验研究  

Experimental Research on the Chaos Characteristics during Reverse Transition

作　　者：张振[1] 颜大椿[2] 

机构地区：[1]航天空气动力技术研究院,北京100074 [2]北京大学工学院力学与工程科学系,北京100871

出　　处：《北京大学学报（自然科学版）》2006年第5期624-627,共4页Acta Scientiarum Naturalium Universitatis Pekinensis

摘　　要：利用逆转捩过程中的瞬时速度时间序列计算了逆转捩过程中反映系统无序运动程度的非线性动力学参数,即相关维数、最大Lyapunov指数和关联熵。计算结果表明,在逆转捩过程中存在混沌现象;逆转捩过程与转捩过程相反,流动形态经历了湍流-混沌-层流的演化过程。Nonlinear dynamics parameters, such as correlation dimension, maximum Lyapunov exponent and Kolmogorov entropy, which reflect the chaos characteristics of flow field are calculated with the time series of instantaneous velocity during reverse transition. Computational results show that chaos exists during reverse transition. Contrary to transition, the flow regimes during reverse transition experience the process of turbulence-chaos-laminar flow.

关 键 词：逆转捩 混沌 湍流 

分 类 号：O357.5[理学—流体力学]