Micromechanical modelling and simulation of functional paper materials

功能纸材料的微机械建模与仿真

• 批准号: 405422877
• 负责人: Professorin Dr.-Ing. Bai-Xiang Xu
• 金额: --
• 依托单位: Fachgebiet Mechanik Funktionaler Materialien
• 依托单位国家: 德国
• 项目类别: Research Grants
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/405422877?language=en
• 关键词: Micromechanical; modelling; simulation; functional; paper

The functionality of paper materials relies on the microstructural details of the paper material to be examined, which, in addition to the used fiber material, is a decisive factor for the functionalization and for the design with regard to specific applications. In the first funding period, a micromechanical model and cohesive finite element simulations have been successfully completed, as well as statistical analysis of the structure-property relation using machine learning from massive simulation results. In the proposed funding period, the chemical functionalizations that are the common focus of various sub-projects and their influence on the mechanical activation of the fibers, the fiber-fiber composite and finally the entire fiber network are to be integrated into the simulation models. The aim is also to investigate the micromechanical properties by means of adapted simulation models in cooperation with the experimentally oriented sub-projects as part of the continuation PAK962-2 in order to gain groundbreaking knowledge with regard to the planned functionalization, under both dry and wet conditions regarding the layout of the design space for functional papers. Furthermore, microscopic details of the paper materials are primarily of a stochastic nature. The apparently spatially statistical arrangement of the fibers and thus the pore structure, which on the one hand depends on the fiber material used and on the other hand is heavily dependent on the manufacturing process, can be examined for microscopic details thanks to modern graphic imaging processes. These methods offer a number of new possibilities to generate practical and most realistic geometry models, which is helpful for numerical simulation calculations. Statistical features can then be analyzed from these models or the model geometry can be obtained directly from the images in order to then carry out the simulation of the mechanical properties. The latter pursues the further aim of using advanced imaging methods to derive a one-to-one microstructure and thus to reconstruct a so-called “digital twin”. This should be used: a) to determine material parameters based on the experiments; b) to validate the simulation models; c) to create reconstruction of geometry models for the simulation; d) to derive statistical characteristics and then construct realistic fiber networks that are statistically evenly distributed. The complex structure-property relationship of the fiber networks through chemical modification is also examined using a sensitivity analysis based on machine learning that has been developed in the first period.

纸材料的功能依赖于要检查的纸材料的微观结构细节，除了所使用的纤维材料外，这是功能化和有关特定应用的设计的决定性因素。在第一个资助期内，成功完成了微观力学模型和内聚有限元模拟，并利用大量模拟结果中的机器学习对结构-性能关系进行了统计分析。在拟议的资助期内，化学功能化是各个子项目的共同重点，它们对纤维、纤维-纤维复合材料以及最后整个纤维网络的机械活化的影响将被纳入模拟模型。作为pak962续篇的一部分，我们的目的是通过与实验导向的子项目合作，通过适应的模拟模型来研究微力学性能，以便在干湿条件下获得关于功能性论文设计空间布局的规划功能方面的突破性知识。此外，纸张材料的微观细节主要具有随机性。纤维的明显的空间统计排列和孔隙结构，一方面取决于所使用的纤维材料，另一方面严重依赖于制造工艺，由于现代图形成像工艺，可以检查微观细节。这些方法为生成实用的、最真实的几何模型提供了许多新的可能性，有助于数值模拟计算。然后可以从这些模型中分析统计特征，或者直接从图像中获得模型几何形状，以便进行力学性能的模拟。后者追求的进一步目标是使用先进的成像方法来获得一对一的微观结构，从而重建所谓的“数字双胞胎”。这应用于：a)根据实验确定材料参数；B)验证仿真模型；C)创建用于仿真的几何模型重建；D)得出统计特征，然后构建统计上均匀分布的现实光纤网络。通过化学改性的光纤网络的复杂结构-性质关系也使用基于机器学习的敏感性分析进行了检查，该敏感性分析已在第一阶段开发。