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Kontakt
| Büro: | EW 268 |
|---|---|
| Telefon: | +49 30 314 28851 |
| Adresse: | Sekr. EW 7-1 Institut für Theoretische Physik Technische Universität Berlin Hardenbergstr. 36 D-10623 Berlin |
| Email: | henning.reinken(a)itp.tu-berlin.de |
Research interests
- Mesoscale turbulence under the influence of an orienting external field
- © AG Klapp
Active fluids show a variety of self-sustained non-equilibrium phenomena. An intriguing example is the emergence of a turbulent state in bacterial suspensions, denoted as mesoscale turbulence. In contrast to turbulence in an ordinary fluid, mesoscale turbulence is characterized by the formation of vortex structures exhibiting a typical length scale. Recent publications have shown that a fourth order field theory for the collective microswimmer velocity describes the main features of mesoscale turbulence, including the emergence of the typical vortex size. Such a fourth order continuum theory that couples the polar order parameter of the microswimmers to the solvent velocity can be derived from a microscopic model via the Focker Planck equation for the probability distribution.
In this work, we extend the theory to include the influence of orienting external fields, such as magnetic fields in the case of magnetotactic bacteria or gravitational fields in the case of gravitactic bacteria. We derive the additional terms in the field equation for the polar order parameter to determine the effects on the state diagram. In addition, we investigate analytically and numerically the influence of such external fields on the emerging structures at the transition to mesoscale turbulence.
Methods: Continuum theory, Fokker-Planck equation, numerical finite-difference and spectral methods, linear stability analysis, weakly nonlinear analysis
Publications
H. Reinken, D. Nishiguchi, S. Heidenreich, Andrey Sokolov, M. Bär, S. H. L. Klapp, I. S. Aranson,
Organizing bacterial vortex lattices by periodic obstacle arrays,
Commun. Phys. 3, 76 (2020).
https://www.nature.com/articles/s42005-020-0337-z
Henning Reinken, Sebastian Heidenreich, Markus Bär, Sabine H. L. Klapp,
Anisotropic mesoscale turbulence and pattern formation in microswimmer suspensions induced by orienting external fields,
New J. Phys. 21, 013037 (2019).
https://doi.org/10.1088/1367-2630/aaff09
Henning Reinken, Sabine H. L. Klapp, Markus Bär, Sebastian Heidenreich,
Derivation of a hydrodynamic theory for mesoscale dynamics in microswimmer suspensions,
Phys. Rev. E 97, 022613 (2018).
https://doi.org/10.1103/PhysRevE.97.022613
Rodrigo Lugo-Frias, Henning Reinken, Sabine H. L Klapp,
Shear banding in nematogenic fluids with oscillating orientational dynamics,
Eur. Phys. J. E 39: 88 (2016).
The final publication is available at Springer via
http://dx.doi.org/10.1140/epje/i2016-16088-3
Talks
Self-organization of microswimmer in arrays of obstacles
Engineering of Chemical Complexity, 10th International Conference, June 2019
Stabilization of a square vortex lattice in microswimmer suspensions by periodic arrays of obstacles
DPG Spring Meeting, 2019, Regensburg
Self-organization of microswimmers in arrays of obstacles
23stes Harzseminar, März 2019, Goslar-Hahnenklee
Asymmetric pattern formation in microswimmer suspensions subjected to orienting external fields
NECD18 - International Conference of GRK1558, October 2018, Potsdam
Mesoscale turbulence in active suspensions subjected to orienting external fields
DPG Spring Meeting, 2018, Berlin
Influence of orienting external fields on the dynamics of mesoscale turbulence
22stes Harzseminar, Februar 2018, Goslar-Hahnenklee
Influence of orienting external fields on the dynamics of mesoscale turbulence
Workshop of GRK 1558, 2017, Templin
Rheology and shear-induced dynamics of polar microswimmers
DPG Spring Meeting, 2017, Dresden
Flow-induced pattern formation in anisotropic fluids
21stes Harzseminar, Februar 2017, Goslar-Hahnenklee
Shear banding in nematogenic fluids
Workshop of GRK 1558, 2016, Bad Schandau-Krippen
Shear-driven instabilities in hard-core anisotropic colloids: Shear banding
DPG Spring Meeting, 2016, Regensburg
Posters
Asymmetric pattern formation in microswimmer suspensions subjected to orienting external fields
Erice Workshop: Self-Organization in Active Matter, October 2018, Erice, Italy
Influence of orienting external fields on the dynamics of mesoscale turbulence
Liquid Matter Conference, July 2017, Ljubljana
Shear banding in nematogenic fluids with oscillating orientational dynamics
3rd International Workshop on Nonlinear Response in Complex Matter, 2016, Primosten, Croatia
Inhomogeneous flow induced dynamics of nematic colloidal binary mixtures
NECD15 – International Conference of GRK 1558, 2015, Potsdam
Inhomogeneous shear-induced alignment of anisotropic binary mixtures
DPG Spring Meeting, 2015, Berlin