Steady-state hydrodynamic instabilities of active liquid crystals: hybrid lattice Boltzmann simulations.
We report hybrid lattice Boltzmann (HLB) simulations of the hydrodynamics of an active nematic liquid crystal sandwiched between confining walls with various anchoring conditions. We confirm the existence of a transition between a passive phase and an active phase, in which there is spontaneous flow...
| Autori principali: | , , , |
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| Natura: | Journal article |
| Lingua: | English |
| Pubblicazione: |
2007
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| _version_ | 1826275811049603072 |
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| author | Marenduzzo, D Orlandini, E Cates, M Yeomans, J |
| author_facet | Marenduzzo, D Orlandini, E Cates, M Yeomans, J |
| author_sort | Marenduzzo, D |
| collection | OXFORD |
| description | We report hybrid lattice Boltzmann (HLB) simulations of the hydrodynamics of an active nematic liquid crystal sandwiched between confining walls with various anchoring conditions. We confirm the existence of a transition between a passive phase and an active phase, in which there is spontaneous flow in the steady state. This transition is attained for sufficiently "extensile" rods, in the case of flow-aligning liquid crystals, and for sufficiently "contractile" ones for flow-tumbling materials. In a quasi-one-dimensional geometry, deep in the active phase of flow-aligning materials, our simulations give evidence of hysteresis and history-dependent steady states, as well as of spontaneous banded flow. Flow-tumbling materials, in contrast, rearrange themselves so that only the two boundary layers flow in steady state. Two-dimensional simulations, with periodic boundary conditions, show additional instabilities, with the spontaneous flow appearing as patterns made up of "convection rolls." These results demonstrate a remarkable richness (including dependence on anchoring conditions) in the steady-state phase behavior of active materials, even in the absence of external forcing; they have no counterpart for passive nematics. Our HLB methodology, which combines lattice Boltzmann for momentum transport with a finite difference scheme for the order parameter dynamics, offers a robust and efficient method for probing the complex hydrodynamic behavior of active nematics. |
| first_indexed | 2024-03-06T23:04:28Z |
| format | Journal article |
| id | oxford-uuid:634e8960-d25c-44f0-939e-e528fd301c9c |
| institution | University of Oxford |
| language | English |
| last_indexed | 2024-03-06T23:04:28Z |
| publishDate | 2007 |
| record_format | dspace |
| spelling | oxford-uuid:634e8960-d25c-44f0-939e-e528fd301c9c2022-03-26T18:12:05ZSteady-state hydrodynamic instabilities of active liquid crystals: hybrid lattice Boltzmann simulations.Journal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:634e8960-d25c-44f0-939e-e528fd301c9cEnglishSymplectic Elements at Oxford2007Marenduzzo, DOrlandini, ECates, MYeomans, JWe report hybrid lattice Boltzmann (HLB) simulations of the hydrodynamics of an active nematic liquid crystal sandwiched between confining walls with various anchoring conditions. We confirm the existence of a transition between a passive phase and an active phase, in which there is spontaneous flow in the steady state. This transition is attained for sufficiently "extensile" rods, in the case of flow-aligning liquid crystals, and for sufficiently "contractile" ones for flow-tumbling materials. In a quasi-one-dimensional geometry, deep in the active phase of flow-aligning materials, our simulations give evidence of hysteresis and history-dependent steady states, as well as of spontaneous banded flow. Flow-tumbling materials, in contrast, rearrange themselves so that only the two boundary layers flow in steady state. Two-dimensional simulations, with periodic boundary conditions, show additional instabilities, with the spontaneous flow appearing as patterns made up of "convection rolls." These results demonstrate a remarkable richness (including dependence on anchoring conditions) in the steady-state phase behavior of active materials, even in the absence of external forcing; they have no counterpart for passive nematics. Our HLB methodology, which combines lattice Boltzmann for momentum transport with a finite difference scheme for the order parameter dynamics, offers a robust and efficient method for probing the complex hydrodynamic behavior of active nematics. |
| spellingShingle | Marenduzzo, D Orlandini, E Cates, M Yeomans, J Steady-state hydrodynamic instabilities of active liquid crystals: hybrid lattice Boltzmann simulations. |
| title | Steady-state hydrodynamic instabilities of active liquid crystals: hybrid lattice Boltzmann simulations. |
| title_full | Steady-state hydrodynamic instabilities of active liquid crystals: hybrid lattice Boltzmann simulations. |
| title_fullStr | Steady-state hydrodynamic instabilities of active liquid crystals: hybrid lattice Boltzmann simulations. |
| title_full_unstemmed | Steady-state hydrodynamic instabilities of active liquid crystals: hybrid lattice Boltzmann simulations. |
| title_short | Steady-state hydrodynamic instabilities of active liquid crystals: hybrid lattice Boltzmann simulations. |
| title_sort | steady state hydrodynamic instabilities of active liquid crystals hybrid lattice boltzmann simulations |
| work_keys_str_mv | AT marenduzzod steadystatehydrodynamicinstabilitiesofactiveliquidcrystalshybridlatticeboltzmannsimulations AT orlandinie steadystatehydrodynamicinstabilitiesofactiveliquidcrystalshybridlatticeboltzmannsimulations AT catesm steadystatehydrodynamicinstabilitiesofactiveliquidcrystalshybridlatticeboltzmannsimulations AT yeomansj steadystatehydrodynamicinstabilitiesofactiveliquidcrystalshybridlatticeboltzmannsimulations |