Author(s)

Shigeomi Chono, Tomohiro Tsuji

Department of Mechanical Engineering, Kochi University of Technology, Kochi, Japan.

We investigate the flow induced by annihilation of a pair of defects in liquid crystals using the Doi theory with the Marrucci-Greco potential, in which the orientation state is described with the orientational distribution function. We have numerically studied both the transient behaviors of two defects with different structures and their velocity field, and estimated the magnitude of the induced velocity. A defect with positive strength moves faster than one with negative strength. The long-range order of the molecular orientation field has a large effect on the annihilation time, and the annihilation time is reduced by increasing the long-range order. We find that flows are induced during the annihilation of a pair of defects and that several vortices are generated in the vicinity of the defects. The maximum velocity is predicted to develop spatially between the two defects just after their annihilation in time. In our simulation, the maximum induced velocity reaches an order of 10 μm/s. The induced velocity increases with increasing long range-order and nematic potential strength.

Complex Fluid, Liquid Crystal, Defect, Annihilation, Generation of Flow

Chono, S. and Tsuji, T. (2018) Numerical Simulation of Liquid Crystal Flow Induced by Annihilation of a Pair of Defects. Open Journal of Fluid Dynamics, 8, 343-360. doi: 10.4236/ojfd.2018.84022.