Highly accurate numerical simulation of wetting and dewetting on flexible substrates including Heat transfer

柔性基材润湿和反润湿的高精度数值模拟（包括传热）

• 批准号: 422800359
• 负责人: Dr.-Ing. Florian Kummer
• 金额: --
• 依托单位: Fachgebiet Strömungsdynamik
• 依托单位国家: 德国
• 项目类别: Priority Programmes
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/422800359?language=en
• 关键词: Highly; accurate; numerical; simulation; wetting

The essence of this project is development of numerical simulation methods. The specific physics to be modeled, respectively simulated, is motivated by the practical experiments planned in the Priority Program 2171 (SPP 2171). In particular, experiments are to be investigated in which wetting or dewetting of flexible surfaces takes place. For this purpose, a corresponding high-precision numerical toolbox for the simulation of three-phase systems, consisting of a flexible solid as well as a liquid and a gaseous phase, was developed in the first funding phase. In the second funding phase of the program, these simulation techniques will be further improved and extended to cover a broader range of experiments. In particular, evaporation effects are now to be taken into account.It is important to note that simulation is a complement to the experiments in SPP 2171 here, as it can act as a magnifying glass, so to speak: it provides insights that experiment cannot. For example, simulations make it possible to determine quantities that are difficult or impossible to measure in experiments due to technical limitations.The complementary simulation of experiments of increasing complexity is planned. At the beginning there will be configurations with simple droplets and liquid bridges. In the further course, the impact behavior of droplets on flexible substrates will be investigated. Evaporation, by heating the substrate, will also be considered. The most challenging simulation, which concludes the project, is a Leidenfrost configuration, i.e. an evaporating droplet which, supported by its own vapor layer, hovers above a heated substrate.The simulation procedure is based on a numerical method for two-phase flows, developed by the applicants. These are mixtures of two immiscible fluids, in this case the printing ink and the ambient air. This setup is now supplemented by a third phase, i.e. a flexible solid. If air, liquid and solid meet, this is referred to as a three-phase contact line. The numerical-mathematical basis for this project is a so-called extended discontinuous Galerkin method, which was specially developed to simulate three-phase flows with contact lines with high accuracy. In particular, the interfaces between air and liquid, as well as the three-phase contact line can be followed with high accuracy. For the given problems, the method has to be combined with a simulation method for solids. Furthermore, the heat transfer as well as the evaporation have to be modeled.

本课题的实质是数值模拟方法的发展。具体的物理建模，分别模拟，是由优先计划2171 （SPP 2171）计划的实际实验的动机。特别要研究的是柔性表面发生润湿或脱湿的实验。为此，在第一个资助阶段开发了一个相应的高精度数值工具箱，用于模拟由柔性固体、液体和气相组成的三相系统。在该计划的第二个资助阶段，这些模拟技术将进一步改进和扩展，以涵盖更广泛的实验。现在特别要考虑到蒸发效应。值得注意的是，模拟是SPP 2171中实验的补充，因为它可以作为放大镜，可以这么说：它提供了实验无法提供的见解。例如，模拟可以确定由于技术限制而在实验中难以或不可能测量的数量。计划对越来越复杂的实验进行补充模拟。一开始会有简单的液滴和液体桥的结构。在接下来的课程中，将研究液滴在柔性基板上的冲击行为。通过加热基材的蒸发也将被考虑。该项目最具挑战性的模拟是Leidenfrost配置，即由自身蒸汽层支撑的蒸发液滴在加热的基板上方盘旋。模拟程序基于申请人开发的两相流数值方法。这是两种不相容流体的混合物，在这种情况下是印刷油墨和周围空气。这种设置现在由第三阶段补充，即柔性固体。如果空气、液体和固体相遇，这被称为三相接触线。该项目的数值数学基础是所谓的扩展不连续伽辽金方法，该方法是专门为模拟具有高精度接触线的三相流动而开发的。特别是，空气和液体之间的界面，以及三相接触线可以高精度地跟踪。对于给定的问题，该方法必须与固体的模拟方法相结合。此外，传热和蒸发都必须建模。