Mathematical Scienaes: Computational Modeling of Swimming Organisms

数学科学：游泳生物的计算模型

• 批准号: 9501048
• 负责人: Lisa Fauci
• 金额: $ 9万
• 依托单位: Tulane University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1995
• 资助国家: 美国
• 起止时间: 1995-08-01 至 1999-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9501048&HistoricalAwards=false
• 关键词: Mathematical; Scienaes; Computational; Modeling; Swimming

Fauci The investigator develops and implements computational methods for modeling the fluid dynamics problems of aquatic animal locomotion across a wide range of animal sizes. Of interest are both the dynamics of a single organism and the relationship of its morphology to its motility properties, and the collective hydrodynamic interactions of groups of swimmers with each other and their environment. Applications studied include bacterial chemotaxis in micropores, spermatozoa motility in the reproductive tract, and the coupling of active and passive tissue properties to the external swimming mechanics of a leech. Bacterial chemotaxis in micropores is of special interest, because the transport behavior of microorganisms through porous media is important in studying the contamination of groundwater supplies. Although bioremediation, the process by which microbes degrade contaminants, has field scale implications, the detailed study of pore-level behavior of the coupled fluid-contaminant-microbial system is essential. The project's computational model includes the detailed analysis of hydrodynamics, contaminant reaction, diffusion and convection, and the chemotactic responses of the swimming microbes. This allows the systematic study of the influence of different parameters, such as swimming speed, diffusion rates, microbial uptake rates, as well as stochastic parameters relating to the likelihood with which microbes change their swimming direction in response to the evolving contaminant field. This is difficult, if not impossible, to examine in a laboratory environment. The project studies the way organisms swim, using computational models. The organisms studied vary in size from bacteria to leeches. Of paramount importance in the study of bacterial transport in micropores is the growth of biofilms. Under certain physical and chemical conditions, microbes adhere to each other and the local pore structure. This biofilm growth affects and is affe cted by the local flow characteristics and contaminant transport. The computational model has the ability to model complex, dynamic fluid-structure interactions. Agglomeration is modeled by exerting appropriate binding stresses between discrete representations of organisms, that may hold them together, or, if fluid stresses are large, may yield and release the organisms. The model is a powerful tool for understanding biofilm processes at a micropore level. This has important consequences for environmental problems.

Fauci 研究人员开发和实施计算方法，用于模拟各种动物大小的水生动物运动的流体动力学问题。 感兴趣的是一个单一的生物体的动力学和它的形态的关系，其运动性能，和集体的流体动力学相互作用的游泳者群体与彼此和他们的环境。 研究的应用包括微孔中的细菌趋化性，生殖道中的精子运动，以及水蛭外部游泳力学的主动和被动组织特性的耦合。 微生物在多孔介质中的迁移行为对研究地下水污染具有重要意义，因此微生物在多孔介质中的趋化性是一个值得关注的问题。 虽然生物修复，微生物降解污染物的过程，具有现场规模的影响，耦合流体污染物-微生物系统的孔隙水平的行为的详细研究是必不可少的。 该项目的计算模型包括流体动力学、污染物反应、扩散和对流以及游动微生物的趋化反应的详细分析。 这允许系统地研究不同参数的影响，例如游动速度、扩散速率、微生物吸收速率以及与微生物响应于不断变化的污染物场而改变其游动方向的可能性有关的随机参数。 这在实验室环境中很难，如果不是不可能的话。 该项目使用计算模型研究生物体游泳的方式。 研究的生物体大小不一，从细菌到水蛭。 在微孔中细菌运输的研究中最重要的是生物膜的生长。 在一定的物理和化学条件下，微生物相互粘附在局部孔隙结构上。 这种生物膜的生长影响并受局部流动特性和污染物输运的影响。 计算模型具有模拟复杂的动态流体-结构相互作用的能力。 团聚是通过施加适当的约束力之间的离散表示的生物体，这可能会保持它们在一起，或者，如果流体应力是大的，可能会产生和释放的生物体。 该模型是一个强大的工具，了解生物膜过程中的一个层次。 这对环境问题有重要影响。