Particle laden flows - theory, analysis and experiment

该研究项目综合了理论、计算和实验，建立了密集颗粒流动的多尺度模型，范围从接近接触颗粒的微观结构动力学到密集悬浮液的宏观流变特性。该项目的理论核心包括近接触颗粒群的力学模型和密集悬浮液的连续统建模和动力学分析。该研究开发了新的Stokesian动力学算法来解决密集悬浮液中缓慢的颗粒相互作用，并通过模拟颗粒如何在微观尺度上集体重新配置以适应施加的外部应变来构建悬浮液流变的连续体模型。新的理论得到了加州大学洛杉矶分校应用数学实验室进行的实验的支持，该实验旨在测试悬浮流变学的预测模型。颗粒流在许多工业应用中都很重要，包括石油和天然气开采、煤炭加工、矿物开采和废水处理。该基础研究项目的结果可用于开发各种应用的定量模型，如采矿工业中的螺旋分离器，惯性微流体装置中的细胞分离和微生物聚集。该项目同时支持研究生和本科生的实验和理论研究。

The research project synthesizes theory, computation and experiments to create multiscale models of dense particulate flows, ranging from microstructural dynamics of nearly contacting particles to the macrorheological properties of dense suspensions. The theoretical core of the project includes both mechanistic models of nearly contacting groups of particles, and continuum modeling and analysis of the dynamics of dense suspensions. The research develops new Stokesian Dynamics algorithms to resolve the slow particle interactions in dense suspensions, and uses simulations of how particles collectively reconfigure on the micro-scale to accommodate applied external strains to construct a continuum model for suspension rheology. New theory is supported by experiments carried out in the Applied Mathematics Laboratory at UCLA to test predictive models of suspension rheology.Particle laden flows are important in many industrial applications including oil and gas extraction, coal processing, mining of minerals, and waste-water treatment. Results from this basic research project can be used to develop quantitative models for such diverse applications as spiral separators in the mining industry, cell separation in inertial microfluidic devices and aggregation of microbes. The project supports both graduate student research and undergraduate research involving experiments and theory.