ERI: Shear-Flow-Driven Coupled Mechanisms as a Means to Actively Control Particle Dissolution

该奖项的全部或部分资金来自《2021年美国救援计划法案》(公法117-2)。固体颗粒在液体中的溶解在自然界中是普遍存在的，它出现在广泛的科学和工业应用中。然而，溶解的基本机制仍然是一个活跃的研究领域。在大多数情况下，颗粒溶解涉及三个基本机制：流体和颗粒动力学、颗粒到周围流体的传质以及颗粒侵蚀。这三种机制是相互耦合的，它们通过复杂的非线性关系相互作用，这些关系并不完全被理解。特别是，流体动力学对流体-颗粒相互作用引起的溶解的影响长期以来被忽视。有强有力的证据表明，局部剪切流增强了从颗粒表面到周围流体的传质。该ERI奖包括高保真的数值模拟、高精度的实验测量和新颖的机器学习技术，这些技术将有助于确定流动在非球形颗粒系统溶解中的关键作用。该ERI奖将集中于1)流体和颗粒运动的耦合动力学、溶解物质的传质以及简单剪切流动中扁平颗粒和不规则形状颗粒的表面侵蚀；以及2)弥合颗粒悬浮液中溶解的微观动力学和宏观描述之间的差距。详细微观尺度动力学的高保真建模，包括任意形状颗粒的缩基建模，将与宏观尺度上颗粒大小和形状的时间演变的种群平衡建模相耦合。研究结果将为通过调整流动剪切率以及颗粒的初始尺寸和几何分布来主动控制颗粒溶解提供指导。这些结果可以应用于广泛的应用，包括生物和化学合成、可再生生物质能源、靶向药物输送、生物材料的降解和可溶解的微型机器人。这项研究将为本科生和研究生提供培训机会，特别是那些来自STEM领域代表性不足的群体的学生。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

This award is funded in whole or in part under the American Rescue Plan Act of 2021 (Public Law 117-2). The dissolution of solid particles in a liquid is ubiquitous in nature and it arises in a wide array of scientific and industrial applications. Nevertheless, the fundamental mechanisms of dissolution are still an active area of research. In most cases, particle dissolution involves three basic mechanisms: fluid and particle dynamics, mass transfer from a particle to the surrounding fluid, and particle erosion. These three mechanisms are coupled, and they interact with each other through complex nonlinear relationships that are not completely understood. In particular, the effect of hydrodynamics on dissolution arising from fluid-particle interactions has long been overlooked. There is strong evidence that local shear flow enhances mass transfer from the particle surface to the surrounding fluid. This ERI award comprises high-fidelity numerical simulations, high-precision experimental measurements, and novel machine learning techniques that together will help identify the critical role of flow in the dissolution of non-spherical particle systems. This ERI award will focus on 1) the coupling dynamics of fluid and particle motion, mass transfer of dissolved species, and surface erosion of prolate and oblate particles and irregularly shaped particles in simple shear flow; and 2) bridging the gap between microscale dynamics and macroscale descriptions of dissolution in suspensions of particles. High-fidelity modeling of detailed microscale dynamics, including reduced-basis modeling of arbitrarily shaped particles, will be coupled to population balance modeling of the temporal evolution of particle size and shape at the macroscale. The results of the research should provide guidance to actively control particle dissolution by adjusting flow shear rate and the initial distribution of particle size and geometry. The results could be applied in a wide array of applications including biological and chemical synthesis, renewable biomass energy, targeted drug delivery, degradation of biomaterials, and dissolvable microrobots. The research will provide training opportunities for undergraduate and graduate students, especially those from groups that are underrepresented in STEM fields.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.