Modelling bacterial behaviour close to a no-slip plane boundary: the influence of bacterial geometry
We describe a boundary-element method used to model the hydrodynamics of a bacterium propelled by a single helical flagellum. Using this model, we optimize the power efficiency of swimming with respect to cell body and flagellum geometrical parameters, and find that optima for swimming in unbounded...
| Main Authors: | , , |
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| Format: | Journal article |
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Royal Society Publishing
2010
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| _version_ | 1797088383545114624 |
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| author | Shum, H Gaffney, E Smith, D |
| author_facet | Shum, H Gaffney, E Smith, D |
| author_sort | Shum, H |
| collection | OXFORD |
| description | We describe a boundary-element method used to model the hydrodynamics of a bacterium propelled by a single helical flagellum. Using this model, we optimize the power efficiency of swimming with respect to cell body and flagellum geometrical parameters, and find that optima for swimming in unbounded fluid and near a no-slip plane boundary are nearly indistinguishable. We also consider the novel optimization objective of torque efficiency and find a very different optimal shape. Excluding effects such as Brownian motion and electrostatic interactions, it is demonstrated that hydrodynamic forces may trap the bacterium in a stable, circular orbit near the boundary, leading to the empirically observable surface accumulation of bacteria. Furthermore, the details and even the existence of this stable orbit depend on geometrical parameters of the bacterium, as described in this article. These results shed some light on the phenomenon of surface accumulation of micro-organisms and offer hydrodynamic explanations as to why some bacteria may accumulate more readily than others based on morphology. |
| first_indexed | 2024-03-07T02:49:16Z |
| format | Journal article |
| id | oxford-uuid:ad1bb94b-12b1-4fb8-901e-6108b2ab99c9 |
| institution | University of Oxford |
| last_indexed | 2024-03-07T02:49:16Z |
| publishDate | 2010 |
| publisher | Royal Society Publishing |
| record_format | dspace |
| spelling | oxford-uuid:ad1bb94b-12b1-4fb8-901e-6108b2ab99c92022-03-27T03:33:20ZModelling bacterial behaviour close to a no-slip plane boundary: the influence of bacterial geometryJournal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:ad1bb94b-12b1-4fb8-901e-6108b2ab99c9Mathematical Institute - ePrintsRoyal Society Publishing2010Shum, HGaffney, ESmith, DWe describe a boundary-element method used to model the hydrodynamics of a bacterium propelled by a single helical flagellum. Using this model, we optimize the power efficiency of swimming with respect to cell body and flagellum geometrical parameters, and find that optima for swimming in unbounded fluid and near a no-slip plane boundary are nearly indistinguishable. We also consider the novel optimization objective of torque efficiency and find a very different optimal shape. Excluding effects such as Brownian motion and electrostatic interactions, it is demonstrated that hydrodynamic forces may trap the bacterium in a stable, circular orbit near the boundary, leading to the empirically observable surface accumulation of bacteria. Furthermore, the details and even the existence of this stable orbit depend on geometrical parameters of the bacterium, as described in this article. These results shed some light on the phenomenon of surface accumulation of micro-organisms and offer hydrodynamic explanations as to why some bacteria may accumulate more readily than others based on morphology. |
| spellingShingle | Shum, H Gaffney, E Smith, D Modelling bacterial behaviour close to a no-slip plane boundary: the influence of bacterial geometry |
| title | Modelling bacterial behaviour close to a no-slip plane boundary: the influence of bacterial geometry |
| title_full | Modelling bacterial behaviour close to a no-slip plane boundary: the influence of bacterial geometry |
| title_fullStr | Modelling bacterial behaviour close to a no-slip plane boundary: the influence of bacterial geometry |
| title_full_unstemmed | Modelling bacterial behaviour close to a no-slip plane boundary: the influence of bacterial geometry |
| title_short | Modelling bacterial behaviour close to a no-slip plane boundary: the influence of bacterial geometry |
| title_sort | modelling bacterial behaviour close to a no slip plane boundary the influence of bacterial geometry |
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