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arXiv · 2208.12221

Controllable particle migration in liquid crystal flows

Magdalena Lesniewska·Nigel Mottram·Oliver Henrich
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Abstract

We observe novel positional control of a colloidal particle in microchannel flow of a nematic liquid crystal. Lattice Boltzmann simulations show multiple equilibrium particle positions, the existence and position of which are tunable using the driving pressure, in direct contrast to the classical Segre-Silberberg effect in isotropic liquids. In addition, particle migration in nematic flow occurs an order of magnitude faster. These new equilibria are determined through a balance of elastic forces, hydrodynamic lift and drag as well as order-flow interactions through the defect structure around the particle.

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Magdalena Lesniewska, Nigel Mottram, Oliver Henrich. 2022-08-25. Controllable particle migration in liquid crystal flows. https://arxiv.org/abs/2208.12221

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