Collaborative Research: A Multiscale Thermo-Hygro-Mechanical Investigation of Fibrous Porous Materials

这项合作研究将探索温度和湿度的隔离微尺度限制如何影响纤维多孔材料（如口罩）的机械性能。纤维多孔材料在复杂环境下的航空航天、生物工程、能源、电子等现有和新兴技术中的应用急剧增长，需要深入了解和量化热和水分对此类系统机械性能的影响。该项目的重点是开发一个数值框架，揭示纤维多孔材料的微观力学及其对宏观性能的影响。该项目的成果将是通过机器学习（ML）信息均匀化的第一种热-湿-力学本构模型，该模型捕捉了纤维多孔材料在现实环境中的机械效应。该研究项目还将为女性和代表性不足的少数民族参与STEM提供难得的机会，使其成为未来数据驱动工程技术的领导者和创新者。该项目旨在开发计算模型，可以准确预测纤维材料在不同温度和湿度的真实环境中的性能。纤维多孔材料的性能将高度依赖于固有的微观结构特征，如随时间变化的蒸汽和水分传输、纤维-蒸汽相互作用、纤维变形、失效机制和微观结构演变。该项目的目标是：1）通过严格的数值研究，揭示了以前没有详细探索过的涉及复杂瞬态多物理相互作用的微尺度现象的新知识，2）开发了一种新方法，该方法结合了基于物理的ML算法来绘制热-湿-力学关系，3）建立一个虚拟材料测试平台，使未来设计具有高机械效率和性能的纤维多孔材料成为可能。这些目标将回答以下两个科学问题：1）在热湿条件共存的情况下，微受限域中局部变形的主要机制是什么？2)暴露在环境条件下的纤维的微观力学是如何通过宏观尺度表现出来的？通过对这些问题的回答，我们可以从微观层面上对纤维与周围环境的相互作用，以及湿度、温度和纤维结构之间的相互作用如何决定纤维多孔材料的整体性能等问题进行深入的了解。该奖项体现了NSF的法定使命，通过使用基金会的知识价值和更广泛的影响评审标准进行评估，被认为值得支持。

This collaborative research will explore how an isolated microscale confinement of temperature and humidity impacts the mechanical performance of a fibrous porous material such as face masks. Dramatic growth in the application of fibrous porous materials in existing and emerging technologies in aerospace, bioengineering, energy, electronics, etc. under complex environments demands an in-depth understanding and quantifying the thermal and moisture effects on mechanical performance of such systems. The project is focused on developing a numerical framework that unveils the micro-mechanics of fibrous porous materials and the impacts on their macroscopic performance. The outcome of this project will be a first-of-a-kind thermo-hygro-mechanical constitutive model through machine learning (ML) - informed homogenization that captures the mechanical effects of fibrous porous materials in a realistic environment. This research project will also provide exceptional opportunities for STEM participation of women and underrepresented minorities to become the future leaders and innovators of data-enabled engineering technologies.This project is to develop computational models that can provide accurate prediction of a fibrous material’s performance in the confinement of a real-world environment with varying thermal and humidity. The fibrous porous material performance will be highly dependent on the inherent microstructural features such as time-dependent vapor and moisture transports, fiber-vapor interactions, fiber deformations, failure mechanisms, and microstructure evolution. The objectives for this project are: 1) uncovering new knowledge in microscale phenomena that have not previously been explored in detail involving complex transient multi-physics interactions through rigorous numerical investigations, 2) developing a novel approach that combines the physics-based ML algorithms to draw thermo-hygro-mechanical relationships, and 3) establishing a virtual material testing platform that enables the future design of fibrous porous materials with high mechanical efficiency and performance. These objectives will answer the following two scientific questions: 1) what are the principal mechanisms of localized deformation in a micro-confined domain with the co-existence of thermal and moisture conditions? 2) how does micromechanics of fiber exposed to environmental conditions manifest through macroscale? Answering these questions will advance the fundamental understanding of interactions between fiber and its surrounding environments at a micro-level and how the interplay between humidity, temperature, and fiber structures defines the performance of fibrous porous materials as a whole.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.