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arXiv · 1609.03861

Optimal boundary control of a simplified Ericksen--Leslie system for nematic liquid crystal flows in $2D$

C. Cavaterra·E. Rocca·H. Wu
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Abstract

In this paper, we investigate an optimal boundary control problem for a two dimensional simplified Ericksen--Leslie system modelling the incompressible nematic liquid crystal flows. The hydrodynamic system consists of the Navier--Stokes equations for the fluid velocity coupled with a convective Ginzburg--Landau type equation for the averaged molecular orientation. The fluid velocity is assumed to satisfy a no-slip boundary condition, while the molecular orientation is subject to a time-dependent Dirichlet boundary condition that corresponds to the strong anchoring condition for liquid crystals. We first establish the existence of optimal boundary controls. Then we show that the control-to-state operator is Fr\'echet differentiable between appropriate Banach spaces and derive first-order necessary optimality conditions in terms of a variational inequality involving the adjoint state variables.

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C. Cavaterra, E. Rocca, H. Wu. 2016-09-13. Optimal boundary control of a simplified Ericksen--Leslie system for nematic liquid crystal flows in $2D$. https://doi.org/10.1007/s00205-017-1095-2

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