Vortex Dynamics and Suppression of Chemical Turbulence in Autocatalytic Reaction-Diffusion Systems

在这个由化学系(化学结构、动力学和机制A)资助的项目中，佛罗里达州立大学的奥利弗·斯坦伯克教授正在研究看似简单的化学反应如何形成复杂的类生命模式。实验室容器中的化学反应可以产生宏观图案，其中包括旋转的螺旋，在红色背景上显示为醒目的蓝色条纹。密切相关的螺旋也作为电现象存在于人类心脏中，在那里它们会导致危及生命的情况，是美国主要的死亡原因之一。斯坦博克教授和他的学生将研究这些螺旋波在厚层中的行为，这些螺旋波在模拟心脏的过程中，专注于具体问题，包括高度变化的影响。他们还将研究如何将这些螺旋固定在与心脏病发作后形成的解剖特征和疤痕组织相对应的惰性区域。本项目使用自催化Belousov-Zhabotinsky(BZ)反应和反应扩散模型的数值模拟来研究自传播浓度波。在三维空间中，这些非线性波可以采取涡旋的形式，绕着称为细丝的一维相位奇点旋转。细丝运动可以产生一种时空混沌，这种混沌在动力学上与人类心脏的室颤有许多相似之处。研究了非反应性非均质对周期涡旋和混沌涡旋的影响，重点研究了缺陷对湍流态的抑制以及涡旋沿台阶边缘的平移运动。另一个组成部分是对高维网络中涡钉扎现象的研究。外展计划包括利用YouTube视频和其他基于互联网的资源向非专业人员和教师传播关键成果和相关背景信息。

In this project funded by the Chemistry Division (Chemical Structure, Dynamics and Mechanisms A), Professor Oliver Steinbock (Florida State University) is studying how seemingly simple chemical reactions can form complex life-like patterns. Chemical reactions in a laboratory container can produce macroscopic patterns that include rotating spirals that appear visually as striking blue bands on a red background. Closely related spirals exist as electrical phenomena also in the human heart where they cause life-threatening conditions and are among the leading causes of death in the US. Professor Steinbock and his students will investigate the behavior of these spiral waves in thick layers that model the heart focusing on specific questions including the effect of height variations. They will also study the pinning of these spirals to inert areas that correspond to anatomical features and scar tissue formed after heart attacks. This project uses the autocatalytic Belousov-Zhabotinsky (BZ) reaction and numerical simulations of reaction-diffusion models to investigate self-propagating concentration waves. In three dimensions, these nonlinear waves can take the form of vortices that rotate around one-dimensional phase singularities called filaments. Filament motion can generate a form of spatio-temporal chaos that shares many dynamical similarities with ventricular fibrillation in the human heart. The effect of non-reactive heterogeneities on periodic and chaotic vortices will be investigated with a focus on the defect-mediated suppression of turbulent states as well as the translational motion of vortices along step edges. Another component is the study of vortex pinning in higher dimensional networks. The outreach program includes the dissemination of key results and pertinent background information to laymen and teachers using YouTube videos and other internet-based resources.