Collective behaviour of model microswimmers

<p>At small length scales, low velocities, and high viscosity, the effects of inertia on motion through fluid become insignificant and viscous forces dominate. Microswimmer propulsion, of necessity, is achieved through different means than that achieved by macroscopic organisms. We describe...

সম্পূর্ণ বিবরণ

গ্রন্থ-পঞ্জীর বিবরন
প্রধান লেখক: Putz, V
অন্যান্য লেখক: Yeomans, J
বিন্যাস: গবেষণাপত্র
ভাষা:English
প্রকাশিত: 2010
বিষয়গুলি:
_version_ 1826315871727910912
author Putz, V
author2 Yeomans, J
author_facet Yeomans, J
Putz, V
author_sort Putz, V
collection OXFORD
description <p>At small length scales, low velocities, and high viscosity, the effects of inertia on motion through fluid become insignificant and viscous forces dominate. Microswimmer propulsion, of necessity, is achieved through different means than that achieved by macroscopic organisms. We describe in detail the hydrodynamics of microswimmers consisting of colloidal particles and their interactions. In particular we focus on two-bead swimmers and the effects of asymmetry on collective motion, calculating analytical formulae for time-averaged pair interactions and verifying them with microscopic time-resolved numerical simulation, finding good agreement.</p><p>We then examine the long-term effects of a swimmer's passing on a passive tracer particle, finding that the force-free nature of these microswimmers leads to loop-shaped tracer trajectories. Even in the presence of Brownian motion, the loop-shaped structures of these trajectories can be recovered by averaging over a large enough sample size.</p><p>Finally, we explore the phenomenon of synchronisation between microswimmers through hydrodynamic interactions, using the method of constraint forces on a force-based swimmer. We find that the hydrodynamic interactions between swimmers can alter the relative phase between them such that phase-locking can occur over the long term, altering their collective motion.</p>
first_indexed 2024-03-06T19:39:16Z
format Thesis
id oxford-uuid:2018148e-336d-4be2-8c8c-c40278bb2d90
institution University of Oxford
language English
last_indexed 2024-12-09T03:34:05Z
publishDate 2010
record_format dspace
spelling oxford-uuid:2018148e-336d-4be2-8c8c-c40278bb2d902024-12-01T17:38:58ZCollective behaviour of model microswimmersThesishttp://purl.org/coar/resource_type/c_db06uuid:2018148e-336d-4be2-8c8c-c40278bb2d90Theoretical physicsCondensed matter theoryEnglishOxford University Research Archive - Valet2010Putz, VYeomans, J<p>At small length scales, low velocities, and high viscosity, the effects of inertia on motion through fluid become insignificant and viscous forces dominate. Microswimmer propulsion, of necessity, is achieved through different means than that achieved by macroscopic organisms. We describe in detail the hydrodynamics of microswimmers consisting of colloidal particles and their interactions. In particular we focus on two-bead swimmers and the effects of asymmetry on collective motion, calculating analytical formulae for time-averaged pair interactions and verifying them with microscopic time-resolved numerical simulation, finding good agreement.</p><p>We then examine the long-term effects of a swimmer's passing on a passive tracer particle, finding that the force-free nature of these microswimmers leads to loop-shaped tracer trajectories. Even in the presence of Brownian motion, the loop-shaped structures of these trajectories can be recovered by averaging over a large enough sample size.</p><p>Finally, we explore the phenomenon of synchronisation between microswimmers through hydrodynamic interactions, using the method of constraint forces on a force-based swimmer. We find that the hydrodynamic interactions between swimmers can alter the relative phase between them such that phase-locking can occur over the long term, altering their collective motion.</p>
spellingShingle Theoretical physics
Condensed matter theory
Putz, V
Collective behaviour of model microswimmers
title Collective behaviour of model microswimmers
title_full Collective behaviour of model microswimmers
title_fullStr Collective behaviour of model microswimmers
title_full_unstemmed Collective behaviour of model microswimmers
title_short Collective behaviour of model microswimmers
title_sort collective behaviour of model microswimmers
topic Theoretical physics
Condensed matter theory
work_keys_str_mv AT putzv collectivebehaviourofmodelmicroswimmers