Field-driven pattern formation in nematic liquid crystals: mesoscopic simulations of electroconvection

Beitrag in einer Fachzeitschrift
(Originalarbeit)


Details zur Publikation

Autor(en): Lee KW, Pöschel T
Zeitschrift: RSC Advances
Jahr der Veröffentlichung: 2017
Band: 7
Heftnummer: 67
ISSN: 2046-2069
Sprache: Englisch


Abstract



As an environment for rich pattern formation, the electroconvection (EC) of nematic liquid crystals (LCs) is studied via fully nonlinear simulations for the first time. Previously, EC was mostly studied by experiments or

by linear/weakly nonlinear hydrodynamic theory for its instability criteria. While the negative dielectric LCs are used in most EC analytical and experimental investigations, EC with positive dielectric LCs is limited to

experiments only, due to their more complex nonlinear behavior. In this work we take a step beyond the existing weakly nonlinear EC research by using a fully nonlinear particle-based simulation. To investigate

the distinct dynamics of positive and negative dielectric LCs, we modified the molecular potential in the LC stochastic rotational model (LC SRD) [Lee et al., J. Chem. Phys., 2015, 142, 164110] to incorporate the

dielectric characteristics and the field-particle interaction. As a result, different convection patterns known in the EC experiments were observed in our simulations, for which those patterns appeared orderly, as a function of external field strength. The simulated director and flow fields correspond to each other well, as found in our experiments. For the positive dielectric LC, we discovered a net directional flow accompanying the travelling EC rolls. This numerical model and its hydrodynamic analysis could be used for precise flow control at the micro-scale, such as nematic colloidal transportation in microfluidics.




 



FAU-Autoren / FAU-Herausgeber

Lee, Kuang-Wu Dr.
Lehrstuhl für Multiscale Simulation of Particulate Systems
Lehrstuhl für Multiscale Simulation of Particulate Systems
Pöschel, Thorsten Prof. Dr.


Zusätzliche Organisationseinheit(en)
Exzellenz-Cluster Engineering of Advanced Materials


Zitierweisen

APA:
Lee, K.-W., & Pöschel, T. (2017). Field-driven pattern formation in nematic liquid crystals: mesoscopic simulations of electroconvection. RSC Advances, 7(67). https://dx.doi.org/10.1039/C7RA06757G

MLA:
Lee, Kuang-Wu, and Thorsten Pöschel. "Field-driven pattern formation in nematic liquid crystals: mesoscopic simulations of electroconvection." RSC Advances 7.67 (2017).

BibTeX: 

Zuletzt aktualisiert 2019-06-03 um 12:03