热射流拟序结构中混沌现象的实验研究

就开放流体系统中的热射流拟序结构的混沌现象进行了实验研究．发现流场在绝对不稳定情况（S＜0.72）下，环涡模式控制了整个流场．此时相空间中对应的动力系统发生倍周期和Hopf分岔，说明动力系统可通过Feigenbaum和RTN途径进入混沌．相关维、相关熵和Lyapunov指数的计算表明：在一定Re数下，动力系统的时间渐近行为已呈混沌态，表现为奇异吸引子，相关维数D2约为3．80．

THE EXPERIMENTAL STUDY OF THE CHAOTIC PHENOMENA OF HEATED JETS

The chaotic phenomena of the coherent structure in the open flow system of heated jetshave been studied by experiments. The present work is concentrated on the relationship betweentypes of the coherent structure in the physical space and asymptotic behaviors of the dynamicalsystem in the phase space.When S = 1 (cold jet), convective instability is everywhere in the flow field. Axisymmetricand belieal modes are the prevailing types of the coherent structure of the jets with two differentnozzle diameters.When...