Modeling the Helical Micro Swimmer and Investigating the Effect of Geometric Parameters on the Microbot Velocity

Microswimmers are usually designed to move in a small stream of fluid, water pipes, or blood vessels. This study was conducted to model helical microswimmers (HMSs) using mathematical models and simulation software. Ultimately, the best modeling approach is introduced by comparing the results of various modeling approaches and the findings of previous researches. The outcomes of microbot modeling by four different approaches are reported in graphs of linear velocity and efficiency changes in terms of helical length, helical pitch, and helical wire radius, and the findings are compared with Wang's Lighthill's graphs. Finally, the best modeling approach with the most similar graph to Wang and Lighthill is introduced. The relationship between linear velocity and kinematic efficiency of the microbot with several helical geometric parameters was confirmed by Wang's results. COMSOL software was used to simulate the rotational and direct motion of the microbot. It was observed that modeling by Lighthill's relations was more similar to Wang's results, and it was more suitable for modeling compared to Gary's and Hancock's relations. It was found that the velocity and efficiency increased when the helical length was increased, and they decreased when the helical wire radius was decreased. Also, increasing the helical pitch, the velocity and efficiency to increase and then decrease, and they had a maximum point. These outcomes are derived from Wang's experiment, mathematical modeling, and simulation.

Keywords:

helical microswimmer , comparing mathematical modelings , simulating motions of helical microswimmers , investigation of the effect of geometric parameters of microswimmer , investigation of the effect of microswimmer's geometric parameters