This title appears in the Scientific Report :
2010
Please use the identifier:
http://dx.doi.org/10.1103/PhysRevE.82.041921 in citations.
Please use the identifier: http://hdl.handle.net/2128/9312 in citations.
Mesoscale Simulations of Hydrodynamic Squirmer Interactions
Mesoscale Simulations of Hydrodynamic Squirmer Interactions
The swimming behavior of self-propelled microorganisms is studied by particle-based mesoscale simulations. The simulation technique includes both hydrodynamics and thermal fluctuations that are both essential for the dynamics of microswimmers. The swimmers are modeled as squirmers, i.e., spherical o...
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Personal Name(s): | Götze, I. |
---|---|
Gompper, G. | |
Contributing Institute: |
Theorie der Weichen Materie und Biophysik; IAS-2 JARA - HPC; JARA-HPC Theorie der Weichen Materie und Biophysik; IFF-2 |
Published in: | Physical Review E Physical review / E, 82 82 (2010 2010) 4 4, S. 041921 041921 |
Imprint: |
College Park, Md.
APS
2010
2010-10-26 2010-10-01 |
Physical Description: |
041921 |
DOI: |
10.1103/PhysRevE.82.041921 |
Document Type: |
Journal Article |
Research Program: |
BioSoft: Makromolekulare Systeme und biologische Informationsverarbeitung |
Series Title: |
Physical Review E
82 |
Subject (ZB): | |
Link: |
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Publikationsportal JuSER |
Please use the identifier: http://hdl.handle.net/2128/9312 in citations.
The swimming behavior of self-propelled microorganisms is studied by particle-based mesoscale simulations. The simulation technique includes both hydrodynamics and thermal fluctuations that are both essential for the dynamics of microswimmers. The swimmers are modeled as squirmers, i.e., spherical objects with a prescribed tangential surface velocity, where the focus of thrust generation can be tuned from pushers to pullers. For passive squirmers (colloids), we show that the velocity autocorrelation function agrees quantitatively with the Boussinesq approximation. Single active squirmers show a persistent random-walk behavior, determined by forward motion, lateral diffusion, and orientational fluctuations, in agreement with theoretical predictions. For pairs of squirmers, which are initially swimming in parallel, we find an attraction for pushers and a repulsion for pullers, as expected. The hydrodynamic force between squirmer pairs is calculated as a function of the center-to-center distances d(cm) and is found to be consistent with a logarithmic distance dependence for d(cm) less than about two sphere diameters; here, the force is considerably stronger than expected from the far-field expansion. The dependence of the force strength on the asymmetry of the polar surface velocity is obtained. During the collision process, thermal fluctuations turn out to be very important and to strongly affect the postcollision velocity directions of both squirmers. |