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Interaction of toroidal swimmers in Stokes flow
1Department of Mathematical Sciences, Worcester Polytechnic Institute, Worcester, Massachusetts 01609, USA.
Physical Review. E
|May 17, 2017
Summary
Researchers numerically studied doughnut-shaped swimmers in fluid. Pairs of these toroidal swimmers showed varied efficiency based on rotation, and complex trajectories emerged for non-aligned swimmers.
Area of Science:
- Fluid dynamics
- Microswimmers
- Theoretical physics
Background:
- Doughnut-shaped objects, or toroidal swimmers, were proposed as hypothetical microswimmers.
- Their propulsion relies on the irreversible nature of their surface rotations in Stokesian fluids.
Purpose of the Study:
- To numerically examine the hydrodynamic interactions between pairs and trios of free toroidal swimmers.
- To understand how their configurations and rotations affect swimming efficiency and trajectories.
Main Methods:
- Numerical simulations were employed to analyze swimmer interactions.
- A regularized Stokeslet framework was used for non-axisymmetric cases.
Main Results:
- In tandem configurations, co-rotating toroidal swimmers enhanced individual efficiency compared to solitary swimming.
- Counter-rotating pairs showed reduced efficiency.
- Non-axisymmetric arrangements led to diverse trajectories, including repulsion and periodic states.
Conclusions:
- The hydrodynamic interactions significantly influence the locomotion of toroidal swimmers.
- Configuration and rotation direction are critical factors determining efficiency and emergent dynamics.
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