Flow quantization and nonequilibrium nucleation of soft crystals

Autor(en)

Arash Nikoubashman, Gerhard Kahl, Christos Likos

Abstrakt

We consider dense systems consisting of ultrasoft, overlapping particles under shear and transport flow, by employing a multiscale simulational approach that combines multiparticle-collision dynamics for the solvent particles with standard molecular dynamics for the solute. We find that the nucleation rates of supercooled liquids can be dramatically accelerated via the shear-induced formation of an intermediate string pattern, which disaggregates after the cessation of shear, leading to the emergence of three-dimensional fcc order. Furthermore we expose these cluster crystals to Poiseuille flow and we establish the emergence of a quantized flow pattern, in which both the height and the width of the fluid stream display well-defined plateaus as a function of the applied pressure gradient. The resulting velocity profiles of the solvent closely resemble plug flow. We explain the emergence of the plateaus by successive fluidization of crystalline layers adjacent to the channel walls and discuss the dependence of the discrete flow on the cluster aggregation parameter. Cluster crystals thus emerge as novel systems with applications on nano-and microfluidic devices, allowing the manipulation of flow in a precisely controlled way.

Organisation(en)

Computergestützte Physik und Physik der Weichen Materie

Externe Organisation(en)

Technische Universität Wien

Journal

Soft Matter

Band

8

Seiten

4121-4131

Anzahl der Seiten

11

ISSN

1744-683X

DOI

https://doi.org/10.1039/c1sm06899g

Publikationsdatum

2012

Peer-reviewed

Ja

ÖFOS 2012

103023 Polymerphysik, 103036 Theoretische Physik, 103015 Kondensierte Materie, 103029 Statistische Physik

Link zum Portal

https://ucrisportal.univie.ac.at/de/publications/21b9934d-9bba-4fcb-b5b1-53118d5ee887