Mathematical Sciences: A Computational Model of Aquatic Animal Locomotion

研究人员将计算机模拟应用于水生动物推进的流体动力学研究。她发展了一个可靠的计算模型，其中流体的运动由不可压缩的Navier-Stokes方程描述，浸没的生物体由经历随时间变化的运动的浸没的弹性结构来模拟。对流动的雷诺数、游泳有机体的几何形状或游泳运动的复杂性没有固有的限制。此外，还可以研究同一流体区域中多个生物的流体动力学相互作用。这项研究的目标是将模拟扩展到不同的游泳模式，如喷气推进，以及划船和波动运动，并将模型扩展到三维，以便研究更真实和复杂的运动。该项目包括浮力对微生物游泳的影响，因此人们可以研究趋地性现象，即相对于重力的运动方向，无论是在单个生物体中还是在集体游泳中。了解水生动物的进化适应以及与微生物相关的生化特性的一个步骤是了解不同游泳形态和运动的力学和水动力学含义。这个项目提供了第一个水生动物运动的计算模型，解决了描述有机体在流体中运动的完整的纳维尔-斯托克斯方程。

The investigator applies computer modelling to the investigation of the fluid dynamics of aquatic animal propulsion. She has developed a reliable computational model in which the fluid motion is described by the incompressible Navier-Stokes equations, and the immersed organism is modelled by an immersed elastic structure undergoing time-dependent motions. No inherent restriction is imposed on the Reynolds number of the flow, on the geometry of the swimming organism, nor on the complexity of the swimming motion. Moreover, fluid dynamic interactions of multiple organisms in in the same domain of fluid can be studied. The goal of this research is to extend the simulations to different modes of swimming such as jet propulsion, as well as rowing and undulatory motion and to extend the model to three dimensions, where more realistic and complex motions can be studied. The project includes the effect of buoyancy on the swimming of microorganisms, so one may study the phenomena of geotaxis, the orientation of movement with respect to gravity, both in single organisms and in collective swimming. One step in understanding the evolutionary adaptations of aquatic animals, as well as the biochemical properties associated with microorganisms, is understanding the mechanical and hydrodynamical implications of different swimming morphologies and motions. This project provides the first computational model of aquatic animal locomotion solves the full Navier-Stokes equations that describe the motion of the organism in the fluid.