Orientational dynamics of the compressible nematic liquid crystals induced by a temperature gradient.

We have carried out a numerical study of a system of hydrodynamic equations including director reorientation, fluid flow, temperature, and density redistribution across a compressible hybrid-oriented liquid crystal (HOLC) cell under the influence of a temperature gradient nablaT directed normal to the restricting surfaces, when the sample is heated both from below and above. Calculations show that under the influence of nablaT the compressible HOLC sample settles down to a stationary flow regime, both with the horizontal u and vertical w components of velocity v, and u is directed in the opposite direction, approximately one order of magnitude less, than the one in the case of an incompressible HOLC cell. The role of hydrodynamic flow in the relaxation processes of the stress tensor components, for a number of dynamic regimes in the compressible HOLC cell containing 4-n-pentyl-4'-cyanobiphenyl, has been investigated.