FLOW WAVES INDUCED BY CHEMICAL WAVE TRAINS TRAINS AND DYNAMIC BEHAVIOR OF SURFACE DEFORMATION WAVES

Belousov-Zhabotinsky（BZ）反应是非平衡开放条件下体系的典型例子。通过对反应扩散机制下的图案动力学进行建模，了解了系统中观察到的螺旋结构和目标图案等自组织现象。我们发现在溶液层中诱导的对流激发化学波。它们是与螺旋波相关的振荡流和与加速化学波（bim波）相关的发达对流。在这项研究中，我们进行了实验和理论的方法来理解奇怪的现象，如流波出现在化学波列。指出了不仅与相应的化学波列相关的Marangoni不稳定性，而且反应物和/或催化剂的全球分布都有效地带来了表面张力驱动的对流。新的发现是：1）在化学螺旋波的激发下，在直径大于15 cm的反应器中观察到了出流波; 2）出流波的流型由靶向螺旋变化。螺旋流波（波长60 mm，旋转周期40 s，传播速度1500μm/s）以化学螺旋波（波长1.0mm，旋转周期20 s，传播速度100μm/s）的模式旋转。3）考虑催化剂和反应物的分布梯度，进行了数值实验。我们观察到化学波的周期性不稳定性和对流结构的周期性变化这两种奇怪的动力学。上述结果已在“从细胞到大脑的复杂系统的动力学方面（2000.11：仙台，日本）”国际会议上报告。特别是，一个新的发现机制的解释将在国际会议上Marangoni对流在德国举行（吉森：2001.9）。

Belousov-Zhabotinsky (BZ) reaction is known as a typical example of the system under non-equilibrium and open conditions. Self-organizations such as spiral structures and target patterns observed in the system have been understood by modeling the pattern dynamics with reaction-diffusion mechanism. We have found convection flows induced in the solution layer exciting chemical waves. They are oscillatory flow associated with the spiral waves and developed convection associated with the accelerating chemical waves (bim waves). In this study, we carried out both experimental and theoretical approaches to understand the curious phenomena such as flow waves appeared in the chemical wave trains. It was pointed out that not only the Marangoni instability associated with the respective chemical wave trains but also a global distribution of reactants and/or catalysts are effective to bring the surface tension driven convection. New findings are1) Outgoing flow waves are observed in a reactor having a large diameter (more than 15 cm) under the excitation of chemical spiral waves,2) The flow waves change their pattern shape from target to spiral. The spiral flow waves (having wavelength 60mm, rotation period 40s, and propagation velocity 1500μm/s) are rotating in the underlying pattern of chemical spiral waves (having wavelenth 1.0mm, rotation period 20s, and propagation velocity 100μm/s).3) Taking the distribution gradients of catalysts and reactants into account numerical experiments are carried out. We observed two curious dynamics of periodic instability in the chemical waves and periodic change in the convection structure.The above results have been reported at an international conference on "Dynamic Aspects of Complex Systems from Cell to Brain (2000.11 : Sendai, Japan)". Especially, a mechanistic explanation of the new findings will be presented in the international conference on Marangoni convection to be held in Germany (Giessen : 2001.9).