Читать книгу Liquid Crystals - Iam-Choon Khoo - Страница 50

One of the most striking properties of liquid crystals is their ability to flow freely while exhibiting various anisotropic and crystalline properties. This dual nature of liquid crystals makes them very interesting materials to study; it also makes theoretical formalism very complex.

The main feature that distinguishes liquid crystals in their ordered mesophases (e.g. the nematic phase) from ordinary fluids is that their physical properties are dependent on the orientation of the director axis ; these orientation flow processes are necessarily coupled, except in very unusual cases (e.g. pure twisted deformation). Therefore, studies of the hydrodynamics of liquid crystals will involve a great deal more (anisotropic) parameters than studies of the hydrodynamics of ordinary liquids.

We begin our discussion by reviewing first the hydrodynamics of an ordinary fluid. This is followed by a discussion of the general hydrodynamics of liquid crystals. Specific cases involving a variety of flow‐orientational couplings are then treated.