Propulsion Modeling and Analysis of a Biomimetic Swimmer

We have studied a biomimetic swimmer based on the motion of bacteria such as Escherichia coli (E. coli) theoretically and experimentally. The swimmer has an ellipsoidal cell body propelled by a helical filament. The performance of this swimmer was estimated by modeling the dynamics of a swimmer in viscous fluid. We applied the Resistive Force Theory (RFT) on this model to calculate the linear swimming speed and the efficiency of the model. A parametric study on linear velocity and efficiency to optimize the design of this swimmer was demonstrated. In order to validate the theoretical results, a biomimetic swimmer was fabricated and an experiment setup was prepared to measure the swimming speed and thrust force in silicone oil. The experimental results agree well with the theoretical values predicted by RFT. In addition, we studied the flow patterns surrounding the filament with a finite element simulation with different Reynolds number (Re) to understand the mechanism of propulsion. The simulation results provide information on the nature of flow patterns generated by swimming filament. Furthermore, the thrust forces from the simulation were compared with the thrust forces from theory. The simulation results are in good agreement with the theoretical results.