Collaborative Research: Integrated Experiments and Modeling for Spatial, Finite, and Fast Rheometry of Graded Hydrogels using Inertial Cavitation

合作研究：利用惯性空化对梯度水凝胶进行空间、有限和快速流变测量的综合实验和建模

• 批准号: 2232426
• 负责人: Jonathan Estrada
• 金额: $ 37.44万
• 依托单位: Regents of the University of Michigan - Ann Arbor
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-06-01 至 2026-05-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2232426&HistoricalAwards=false
• 关键词: Collaborative; Research; Integrated; Experiments; Modeling

Until recently, inertial cavitation—the rapid, unstable growth and collapse of bubbles—has been best known as a damaging agent in environments such as pumps, coatings, and bodily tissues. Current advances in medicine aim to harness inertial cavitation to cut tissues noninvasively using ultrasound, but this goal is limited by available data. A present challenge is that tissues and various soft material systems are complex, with interfaces and stiffness gradients along different internal directions. This award supports characterizing, modeling, and predicting the mechanical response of non-uniform soft materials subject to rapid bubble collapse and oscillation. This knowledge could be used, for example, to speed up assessment during ultrasound-based surgery and provide critical insight into mitigating injury from rapid forces. Thus, the research will not only promote the progress of science but will also advance national health, prosperity, and welfare. This project will further train students working across disciplines of fluid and solid mechanics, and materials science. The team will encourage scientific learning in a broad early-learner audience via the development of two children's books written in multiple languages and outreach activities about soft material mechanics.A single test probing ultra-high-rate and finite deformation regimes of materials simultaneously has been elusive. Prior work has established inertial cavitation rheometry as a promising candidate, but the technique restrictively assumes spherical symmetry. This project aims to leverage quantities surrounding asphericity—regarded as a problem in the original technique—as a critical metric for assessing local material gradients. A multi-perspective, ultra-high-rate microscopy platform for characterizing graded, ultraviolet-light-tunable hydrogels using bubble kinematics, and full-field deformations determined via embedded speckle plane-based digital image correlation comprise the experimental setup. Concurrently, numerical methods leveraging (a) full-field kinematic fields with simulation and (b) bubble shape perturbation information with a modified 1D-perturbation model of the governing equations of motion and conservation will establish a suite of baseline problems. Together, critical measurable quantities in the inverse calibration problem will be used to establish a fast reduced-order model for describing both material behavior and gradients therein. This approach will provide a methodology for producing linearly graded hydrogels, a database of ultra-high-rate, finite viscoelastic hydrogel behavior, upgraded inverse-calibration procedures leveraging spherical perturbations and simulations, and a reduced-order approach for fast rheology without, with, or with-coupled property gradients.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.

直到最近，在泵，涂料和身体组织等环境中，惯性空化（快速，不稳定的生长和气泡塌陷）一直是损害剂。目前的医学进展旨在利用惯性空化来使用超声进行脱落组织，但该目标受到可用数据的限制。当前的挑战是，组织和各种软材料系统都是复杂的，沿不同内部方向的界面和刚度梯度。该奖项支持表征，建模和预测受气泡塌陷和振荡的非均匀软材料的机械响应。例如，可以使用这些知识来加快基于超声手术的评估，并为缓解快速力量的损伤提供批判性的见解。这项研究不仅将促进科学的进步，而且还将促进国家健康，繁荣和福利。该项目将进一步培训跨流体和固体力学和材料科学学科工作的学生。该团队将通过开发用多种语言编写的两种儿童读物和有关软材料机制的外展活动来鼓励在广泛的早期学习者中进行科学学习。一种材料的超高速率和有限的变形方案的单次测试探测根本难以捉摸。先前的工作已将惯性气态变流变体作为有前途的候选者，但是该技术限制性地假定了球形对称性。该项目旨在利用围绕非球面的数量（作为原始技术中的问题）作为评估当地材料梯度的关键指标。一个多探针，超高的显微镜平台，用于使用气泡运动学来表征分级，紫外线 - 触发水凝胶，以及通过基于嵌入式斑点平面的数字图像相关性确定的全场变形，同时使用嵌入式斑点平面图像相关性，同时使用数值，数值的方法（a）具有仿真和替代的模型（a）的模型（a）拟态的模型（A）在理事方程式和保护方程中，将建立一套基线问题。总之，将使用反向校准问题中的临界测量量来建立一个快速降低阶模型，以描述其中的材料行为和其中的梯度。这种方法将提供一种方法来生产线性分级水凝胶，一个超高率，有限的粘粘性水凝胶行为的数据库，升级的逆计算程序利用了逆向扰动和模拟的逆验证程序，以及降低了降低的级别流感学的方法，没有，与之相关的物业级别的宣布。使用基金会的智力优点和更广泛的影响评估标准进行评估。