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Published on: February 17, 2019
Hydrodynamics of linked sphere model swimmers
G P Alexander1, C M Pooley, J M Yeomans
1Rudolf Peierls Centre for Theoretical Physics, 1 Keble Road, Oxford OX1 3NP, UK.
Summary
We detail the hydrodynamics of linked sphere swimmers. Their flow fields and interactions depend on swimmer parameters and stroke phase, highlighting time reversal symmetry
Area of Science:
- Fluid dynamics
- Microswimmer hydrodynamics
- Non-Newtonian fluid mechanics
Background:
- Understanding microswimmer behavior is crucial for applications in targeted drug delivery and micro-robotics.
- The hydrodynamics of simple models provide foundational insights into complex fluid-structure interactions.
Purpose of the Study:
- To provide a detailed analysis of the hydrodynamics of linked sphere microswimmers.
- To elucidate the relationship between swimmer parameters, swimming stroke, and generated flow fields.
- To investigate inter-swimmer interactions in dilute suspensions.
Main Methods:
- Calculation of asymptotic forms for time-averaged flow fields.
- Analysis of hydrodynamic interactions between multiple swimmers.
- Emphasis on the role of time reversal symmetry in far-field flow patterns.
Main Results:
- The time-averaged flow field of a single swimmer is characterized and shown to depend on swimmer parameters and stroke dynamics.
- Interactions between swimmers in dilute suspensions are quantified.
- The significance of time reversal symmetry in dictating far-field flow is demonstrated.
- Swimmer interactions are shown to be highly sensitive to the relative phase of their swimming strokes.
Conclusions:
- The study provides a detailed hydrodynamic model for linked sphere swimmers.
- Time reversal symmetry is a key factor in determining the flow fields generated by these microswimmers.
- Inter-swimmer interactions are complex and strongly influenced by the synchronization and phase of their movements.
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