摘要
文章以反应扩散系统为例 ,介绍了在可激发系统与振荡系统中螺旋波产生、发展、演化的一些基本性质及规律 ,并讨论了作者近年来对螺旋波的各种失稳途径、时空混沌的产生机理及螺旋波控制方面所做的实验与理论工作 .重点讨论了两类螺旋波失稳现象 :爱克豪斯失稳与多普勒失稳 .两类失稳都使系统从有规律的螺旋波态变为时空混沌 (缺陷湍流 )态 .
Using a reaction diffusion system as an example,we introduce the basic properties of spiral waves in excitable or oscillatory media,and discuss different routes that lead from an ordered spiral state to a chaotic state.First we present some basic properties of spiral dynamic,such as its emergence,development,and transition.Then we discuss our recent experimental results on the spiral instabilities of the Belosov Zhabotinsky reaction in a quasi two dimensional reaction diffusion system.Two routes leading to spatio temporal turbulence have been observed in the experiments.Both of them can be characterized by defect mediated turbulence.The first instability is due to the Eckhaus instability,which generates defects at a distance from the spiral center because of its“convective”nature.The second instability creates defects in the spiral center.The mechanism of the instability is linked to the Doppler effect,when a Hopf bifurcation contributes to the spiral core,making the latter meandering.
出处
《物理》
CAS
北大核心
2001年第1期30-36,共7页
Physics
基金
国家杰出青年科学基金资助项目
