Fluid Dynamics of Crossflow Filtration in Suspension-Feeding Fishes

悬浮饲养鱼类错流过滤的流体动力学

• 批准号: 0131293
• 负责人: Sarah Sanderson
• 金额: $ 21.87万
• 依托单位: College of William and Mary
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-03-01 至 2006-02-28
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0131293&HistoricalAwards=false
• 关键词: Fluid; Dynamics; Crossflow; Filtration; Suspension

This project will investigate the fluid dynamics of crossflow filtration in suspension-feeding fishes such as menhaden, anchovy, and carp. These fishes filter massive volumes of water to extract suspended food particles that are as small as 5 micrometer to 1 mm in diameter. Although they comprise approximately 25% of the world fish catch and have filtration efficiencies approaching those of industrial filters, the mechanisms that they use to trap their tiny prey remain largely unknown. A miniature fiberoptic endoscope has been used recently to observe particle movement inside the oral cavities of live suspension-feeding fishes. These data, combined with computational fluid dynamics simulations in fish oral cavities, have led to the development of a new model involving crossflow filtration in suspension-feeding fishes. Although crossflow filtration is a multi-billion dollar industry for the manufacture of products that we use every day (e.g., dairy products, beer and wine, pharmaceuticals), this filtration mechanism had not been recognized previously in any vertebrate. During crossflow filtration in fishes, particles are concentrated inside the oral cavity as filtrate exits between the gill rakers, but particles are not retained on the rakers. Instead, the high-velocity crossflow along the rakers carries particles away from the raker surfaces and transports the particles towards the esophagus. Equations from the industrial filtration engineering literature could be used to calculate the hydrodynamic forces on particles and the resulting particle velocities and trajectories during crossflow filtration in fishes. However, values that are appropriate for suspension-feeding fishes must be used in place of the variables in the equations. The empirical data needed for the first quantitative analysis of biological crossflow filtration will be provided by laboratory experiments involving sonomicrometry, pressure transduction, fiberoptic endoscopy, high-speed video, and flow velocity measurement with micro-thermistor probes. This analysis will provide insight into the process of crossflow filtration as it determines the sizes and densities of particles that suspension-feeding fishes retain. The study will engage undergraduate and Masters students in interdisciplinary research that has important ecological, evolutionary, and engineering implications.

本项目将研究悬浮式摄食性鱼类，如鲱鱼、凤尾鱼和鲤鱼的横流过滤的流体动力学。这些鱼过滤大量的水，以提取直径小至5微米至1毫米的悬浮食物颗粒。尽管它们占世界渔获量的大约25%，过滤效率接近工业过滤器，但它们用来诱捕微小猎物的机制在很大程度上仍不清楚。最近，一种微型光纤内窥镜被用来观察悬浮饲养的活鱼口腔内的颗粒运动。这些数据与鱼类口腔中的计算流体力学模拟相结合，导致了一种新的模型的开发，该模型涉及悬浮饲养鱼类的横流过滤。虽然横流过滤是一个价值数十亿美元的行业，用于生产我们每天使用的产品(例如乳制品、啤酒和葡萄酒、药品)，但这种过滤机制以前从未在任何脊椎动物中被认识到。在鱼的横流过滤过程中，当滤液从鳃之间流出时，颗粒会集中在口腔内，但颗粒不会保留在叉子上。取而代之的是，沿着坡口的高速横流将颗粒从坡口表面带走，并将颗粒输送到食道。工业过滤工程文献中的公式可以用来计算鱼类横流过滤过程中对颗粒的水动力以及由此产生的颗粒速度和轨迹。然而，公式中的变量必须用适合于悬浮式鱼类的值来代替。第一次生物横流过滤定量分析所需的经验数据将由实验室实验提供，这些实验包括声学显微测量、压力传递、光纤内窥镜、高速视频和微型热敏电阻探头的流速测量。这一分析将提供对横流过滤过程的洞察，因为它确定了悬浮摄食性鱼类保留的颗粒的大小和密度。这项研究将使本科生和硕士研究生参与具有重要的生态学、进化论和工程学意义的跨学科研究。