Regensburg 2013 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

CPP: Fachverband Chemische Physik und Polymerphysik

CPP 41: Colloids and Complex Liquids I

CPP 41.4: Hauptvortrag

Donnerstag, 14. März 2013, 10:30–11:00, H40

Mesoscale Simulations of Active Colloids — •Gerhard Gompper — Institute of Complex Systems, Forschungszentrum Juelich, Germany

Both in soft matter and in biology, there are numerous examples of swimmers and self-propelled particles. With a typical size in the range of a several micro-meters, both low-Reynolds-number hydrodynamics and thermal fluctuations are essential to determine their dynamics. Prominent examples are bacteria like E. coli which move forward by a rotational motion of their spiral-shaped flagella, and synthetic Janus colloids which catalyze a chemical reaction on their surface.

A powerful tool to study the non-equilibrium dynamics of active are mesoscale hydrodynamics simulation techniques, such as multi-particle collision dynamics (MPC), which describe the hydrodynamic behavior of a wide range of complex fluids very well [1].

We focus here on the cooperative behavior of active spherical and rod-like colloids [2], and on the dynamic properties of individual microswimmers near surfaces [3]. Active colloids display a strong surface excess in confined geometries and a pronounced clustering behavior in the bulk. The effects of self-propulsion, hydrodynamic interactions, microswimmer shape, and noise on these phenomena will be discussed.

[1] G. Gompper, T. Ihle, D.M. Kroll, R.G. Winkler, Adv. Polym. Sci. 221, 1 (2009).

[2] Y. Yang, V. Marceau, G. Gompper, Phys. Rev. E 82, 031904 (2010); I.O. Goetze & G. Gompper, Phys. Rev. E 82, 041921 (2010).

[3] J. Elgeti & G. Gompper, EPL 85, 38002 (2009).