Squirmer hydrodynamics near a periodic surface topography
The behaviour of microscopic swimmers has previously been explored near large-scale confining geometries and in the presence of very small-scale surface roughness. Here, we consider an intermediate case of how a simple microswimmer, the tangential spherical squirmer, behaves adjacent to singly and d...
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| Format: | Article |
| Language: | English |
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Frontiers Media S.A.
2023-04-01
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| Series: | Frontiers in Cell and Developmental Biology |
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| Online Access: | https://www.frontiersin.org/articles/10.3389/fcell.2023.1123446/full |
| _version_ | 1797847703423549440 |
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| author | Kenta Ishimoto Eamonn A. Gaffney David J. Smith |
| author_facet | Kenta Ishimoto Eamonn A. Gaffney David J. Smith |
| author_sort | Kenta Ishimoto |
| collection | DOAJ |
| description | The behaviour of microscopic swimmers has previously been explored near large-scale confining geometries and in the presence of very small-scale surface roughness. Here, we consider an intermediate case of how a simple microswimmer, the tangential spherical squirmer, behaves adjacent to singly and doubly periodic sinusoidal surface topographies that spatially oscillate with an amplitude that is an order of magnitude less than the swimmer size and wavelengths that are also within an order of magnitude of this scale. The nearest neighbour regularised Stokeslet method is used for numerical explorations after validating its accuracy for a spherical tangential squirmer that swims stably near a flat surface. The same squirmer is then introduced to different surface topographies. The key governing factor in the resulting swimming behaviour is the size of the squirmer relative to the surface topography wavelength. For instance, directional guidance is not observed when the squirmer is much larger, or much smaller, than the surface topography wavelength. In contrast, once the squirmer size is on the scale of the topography wavelength, limited guidance is possible, often with local capture in the topography troughs. However, complex dynamics can also emerge, especially when the initial configuration is not close to alignment along topography troughs or above topography crests. In contrast to sensitivity in alignment and topography wavelength, reductions in the amplitude of the surface topography or variations in the shape of the periodic surface topography do not have extensive impacts on the squirmer behaviour. Our findings more generally highlight that the numerical framework provides an essential basis to elucidate how swimmers may be guided by surface topography. |
| first_indexed | 2024-04-09T18:15:40Z |
| format | Article |
| id | doaj.art-734d443780384ec693fcc3c21b6e74f0 |
| institution | Directory Open Access Journal |
| issn | 2296-634X |
| language | English |
| last_indexed | 2024-04-09T18:15:40Z |
| publishDate | 2023-04-01 |
| publisher | Frontiers Media S.A. |
| record_format | Article |
| series | Frontiers in Cell and Developmental Biology |
| spelling | doaj.art-734d443780384ec693fcc3c21b6e74f02023-04-13T04:34:21ZengFrontiers Media S.A.Frontiers in Cell and Developmental Biology2296-634X2023-04-011110.3389/fcell.2023.11234461123446Squirmer hydrodynamics near a periodic surface topographyKenta Ishimoto0Eamonn A. Gaffney1David J. Smith2Research Institute for Mathematical Sciences, Kyoto University, Kyoto, JapanWolfson Centre for Mathematical Biology, Mathematical Institute, University of Oxford, Oxford, United KingdomSchool of Mathematics, University of Birmingham, Birmingham, United KingdomThe behaviour of microscopic swimmers has previously been explored near large-scale confining geometries and in the presence of very small-scale surface roughness. Here, we consider an intermediate case of how a simple microswimmer, the tangential spherical squirmer, behaves adjacent to singly and doubly periodic sinusoidal surface topographies that spatially oscillate with an amplitude that is an order of magnitude less than the swimmer size and wavelengths that are also within an order of magnitude of this scale. The nearest neighbour regularised Stokeslet method is used for numerical explorations after validating its accuracy for a spherical tangential squirmer that swims stably near a flat surface. The same squirmer is then introduced to different surface topographies. The key governing factor in the resulting swimming behaviour is the size of the squirmer relative to the surface topography wavelength. For instance, directional guidance is not observed when the squirmer is much larger, or much smaller, than the surface topography wavelength. In contrast, once the squirmer size is on the scale of the topography wavelength, limited guidance is possible, often with local capture in the topography troughs. However, complex dynamics can also emerge, especially when the initial configuration is not close to alignment along topography troughs or above topography crests. In contrast to sensitivity in alignment and topography wavelength, reductions in the amplitude of the surface topography or variations in the shape of the periodic surface topography do not have extensive impacts on the squirmer behaviour. Our findings more generally highlight that the numerical framework provides an essential basis to elucidate how swimmers may be guided by surface topography.https://www.frontiersin.org/articles/10.3389/fcell.2023.1123446/fullmicroswimminglow Reynolds number flowcell motilityconfinementsurface topography |
| spellingShingle | Kenta Ishimoto Eamonn A. Gaffney David J. Smith Squirmer hydrodynamics near a periodic surface topography Frontiers in Cell and Developmental Biology microswimming low Reynolds number flow cell motility confinement surface topography |
| title | Squirmer hydrodynamics near a periodic surface topography |
| title_full | Squirmer hydrodynamics near a periodic surface topography |
| title_fullStr | Squirmer hydrodynamics near a periodic surface topography |
| title_full_unstemmed | Squirmer hydrodynamics near a periodic surface topography |
| title_short | Squirmer hydrodynamics near a periodic surface topography |
| title_sort | squirmer hydrodynamics near a periodic surface topography |
| topic | microswimming low Reynolds number flow cell motility confinement surface topography |
| url | https://www.frontiersin.org/articles/10.3389/fcell.2023.1123446/full |
| work_keys_str_mv | AT kentaishimoto squirmerhydrodynamicsnearaperiodicsurfacetopography AT eamonnagaffney squirmerhydrodynamicsnearaperiodicsurfacetopography AT davidjsmith squirmerhydrodynamicsnearaperiodicsurfacetopography |