UNS:Collaborative Research: Transport and Chemotaxis of Swimming Cells in Porous Media Flows

CBET 1510768/1511340PI：Dunkel，Joern/Guasto，Jeffrey该项目的目标是确定控制多孔介质中游泳细胞运输和趋化的物理机制。许多种类的细胞都能在液体中产生自身的推进力。在它们的自然栖息地和工程系统中，游泳细胞必须在复杂的微结构中导航，以响应来自食物来源和其他生物的各种化学信号。研究人员将使用理论、数值模拟和实验相结合的方法来检查流体流动、边界结构和化学刺激对单个细胞和细胞集合运动的相对重要性。其结果将适用于生态过程和各种技术，包括生物反应器、生物修复和清洁水的保护。当地高中生将被招募参与该项目。游泳细胞和合成自行式颗粒组成了一类新兴的主动悬浮，其传输特性可能与被动标量和颗粒流显著不同。我们将研究悬浮微结构和流动对细胞在多孔介质中传输的影响，以研究跨越典型游泳风格和身体形状的各种细胞的稀薄和致密悬浮。微流控装置将被设计成创造良好控制的环境，模拟多孔介质中的自然流动条件和化学梯度。微生物悬浮液的高速视频显微镜将提供大型细胞群体的统计特征，以及鞭毛和流体动力学相互作用调节大规模行为的机械细胞尺度视图。多孔介质结构对化学梯度中趋化细胞的传输系数的影响也将被检验。连续体和基于粒子的模型将被数值实现，结果将与实验进行系统地验证，以建立一个定量的、预测多孔介质流动中活跃细胞传输的框架。

CBET 1510768 / 1511340PIs: Dunkel, Joern / Guasto, JeffreyThe goal of this project is to determine the physical mechanisms that govern transport and chemotaxis of swimming cells in porous media. Many kinds of cells are capable of generating their own propulsion in liquids. In their natural habitats and in engineered systems, swimming cells have to navigate through complex microstructures in response to various chemical signals from food sources and other organisms. The investigators will use a combination of theory, numerical simulation, and experiments to examine the relative importance of fluid flows, boundary structures and chemical stimuli on the locomotion of individual cells and collections of cells. The results will be applicable to ecological processes and diverse technologies, including bioreactors, bioremediation, and preservation of clean water. Local high-school students will be recruited to participate in the project.Swimming cells and synthetic self-propelled particles comprise an emerging class of active suspensions, whose transport properties can differ significantly from those of passive scalars and particulate flows. The effects of suspension microstructure and flow on cell transport in porous media will be investigated for dilute and dense suspensions of various cells that span canonical swimming styles and body shapes. Microfluidic devices will be designed to create well-controlled environments that simulate natural flow conditions and chemical gradients in a porous medium. High-speed video microscopy of microbial suspensions will provide a statistical characterization of large cell ensembles as well as a mechanistic cell-scale view of the flagellar and hydrodynamic interactions mediating large-scale behaviors. The effects of porous media structure on the transport coefficients of chemotaxing cells in chemical gradients will also be examined. Continuum and particle-based models will be implemented numerically and results will be systematically validated against experiments to establish a quantitative, predictive framework for active cell transport in porous media flows.