Particle laden flows - theory, analysis and experiment

该研究项目综合了理论、计算和实验，以建立致密颗粒流的多尺度模型，范围从几乎接触的颗粒的微观结构动力学到致密悬浮液的宏观流变特性。该项目的理论核心包括几乎接触的颗粒群的力学模型，以及稠密悬浮动力学的连续介质建模和分析。该研究开发了新的Stokesian动力学算法来解决稠密悬浮液中缓慢的颗粒相互作用，并利用模拟颗粒如何在微观尺度上重新配置以适应外加应变来构建悬浮液流变学的连续介质模型。新的理论得到了加州大学洛杉矶分校应用数学实验室对悬浮流变学预测模型的实验的支持。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、矿产开采和废水处理。这一基础研究项目的结果可用于开发各种应用的定量模型，如矿业中的螺旋分离器、惯性微流控装置中的细胞分离和微生物聚集。该项目支持研究生研究和涉及实验和理论的本科生研究。

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.