A combined experimental and numerical approach to study the hierarchy of multiscale structures arising from the stationary solutal Marangoni instability

实验和数值相结合的方法来研究由静止溶质马兰戈尼不稳定性引起的多尺度结构的层次结构

• 批准号: 167363687
• 负责人: Privatdozent Dr. Thomas Boeck
• 金额: --
• 依托单位: Institut für Verfahrenstechnik und Umwelttechnik
• 依托单位国家: 德国
• 项目类别: Priority Programmes
• 财政年份: 2010
• 资助国家: 德国
• 起止时间: 2009-12-31 至 2016-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/167363687?language=en
• 关键词: combined; experimental; numerical; approach; study

Mass transfer across liquid interfaces is frequently accompanied by solutal Marangoni convection with complex and irregular flow structures. This so-called interfacial turbulence, which can significantly enhance mass transfer rates, is of considerable importance in chemcial engineering, e.g. in liquid-liquid extraction processes. Interfacial turbulence is known to evolve progressively from small to large lengthscales by a cascade-like process, where larger and larger structures emerge on a background of smaller flow structures. This hierarchical evolution displays a characteristic sequence of flow structures before it is repeated on a significantly larger length scale. The details of this evolution and the characteristic properties of the various flow structures and their transformations are only poorly understood. These deficiencies will be addressed by the project through a combination of accurate experiments with novel techniques for optical flow measurement, and by highly resolved numerical simulations. The particular configuration to be studied is a liquid-liquid system, composed of two immiscible solvents separated by a plane interface. Solutes of different surfaceactivity together with a tuning of solvent system and container geometry will be used to select different hierarchy levels of the interfacial turbulence cascade. The mathematical model incorporates the ow in both liquid phases in connection with a separate transport equation of the interfacial concentration and takes a nonlinear sorption kinetics of the surfactant into account. Relevant data to the generic structures of interfacial turbulence at a plane interface will be provided to other projects of the priority programme in benchmark quality. In the second period, structures of higher order in the turbulence cascade will be addressed. Beside the potential to refine mass transfer models, the detailed understanding of interfacial turbulence will open important conceptual links to other areas of nonlinear dynamics such as reaction-diffusion systems.“

跨液体界面的传质经常伴随着具有复杂和不规则流动结构的溶液马兰戈尼对流，这种所谓的界面湍流可以显着提高传质速率，在化学工程（例如液-液萃取过程）中具有相当重要的意义。众所周知，界面湍流通过类似级联的过程从小尺度逐渐演化到大尺度，在较小的流动结构的背景上出现越来越大的结构。在以更大的长度尺度重复之前，对流结构的特征序列的了解很少，该项目将通过组合来解决这些缺陷。利用光流测量新技术和高分辨率数值模拟进行精确实验。要研究的特定配置是由两种不混溶的溶剂组成，这些溶剂通过平面界面分开，并具有不同的表面活性。溶剂系统和容器几何形状将用于选择界面湍流级联的不同层级。该数学模型将两个液相中的流动与界面浓度的单独传输方程结合起来，并考虑表面活性剂的非线性吸附动力学相关数据。平面界面处的界面湍流的通用结构将以基准质量提供给优先计划的其他项目。在第二阶段，将提供湍流级联中的更高阶结构。除了完善传质模型的潜力之外，对界面湍流的详细理解还将打开与非线性动力学其他领域（例如反应扩散系统）的重要概念联系。