Computational Modeling of Micro-Swimmer: Fluid-Structure Interaction

In this study we will be looking at numerical modeling of a micro-swimmer. The micro-swimmer is simplified as a single flagellum immersed in Newtonian fluid. It is discretized into points joined by elastic linear and torsion springs. An active moment is applied along the entire length of swimmer. Fluid equations are solved using the Projection Method and swimmer-fluid couplings are accomplished using the Immersed Boundary Method. We validate the case of a swimmer confined between two narrow walls with results from literature. Next we verify that hydrodynamic effects contributed by the walls allow swimmers to swim at higher velocities. We show that for a given wave amplitude of the swimmer, narrowing the walls of the confining channel increases the velocity of the swimmer. In addition, for a given swimmer velocity, narrowing the walls of the confining channel allows the swimmer to expand less energy. We also investigate the hydrodynamic effects from the presence of a second swimmer and show that the presence of a second swimmer may have a significant effect on the locomotion of both swimmers.