Point of departure is an extended Kirkwood-Smoluchowski (K-S) equation for the pair-correlation function (PCF) which is applicable to a rather large range of shear rates. A solution procedure for the K-S equation in a stationary plane Couette-flow (simple shear flow) is outlined where the...

A theory for nonequilibrium phenomena primarily associated with the molecular orientation in liquids and liquid crystals is developed within the framework of irreversible thermodynamics. The alignment tensors of rank 2 and 4 are taken into consideration as additional macroscopic variables. With...

A nonlinear inhomogeneous relaxation equation for the friction pressure is derived from the Boltzmann equation with the help of the moment method. Nonlinear terms emerge from both the flow term and the quadratic part of the Boltzmann collision operator. The importance of the latter contributions...

The thermodynamic functions like the internal energy, the entropy, the pressure and the Gibbs free energy are expanded with respect to scalars constructed from the components of the alignment tensors specifying the orientations of the molecules. Microscopic expressions are derived for the...

After some general remarks on order in fluids and the anisotropy of distribution functions, results obtained by theoretical considerations and by nonequilibrium molecular dynamics computer simulations are presented for two specific examples. These are the influences of a shear flow, firstly, on...

A generalized Fokker-Planck equation for the bond-orientational distribution function is formulated. Torques are taken into account which stem from a mean field proportional to a fourth rank anisotropy tensor specifying a state with cubic symmetry and from the gradient of a flow velocity field....

Based on a relaxation equation for the alignment tensor characterizing the molecular orientation in liquid crystals under flow we present results for the full orientational dynamics of homogeneous liquid crystals in a shear flow. We extend the analysis of the symmetry-adapted states by...

The method of non-equilibrium molecular dynamics, with special emphasis on the simulation of a plane Couette flow, and results for simple fluids are reviewed briefly. Then simulation data are presented for complex fluids, in particular for polymeric liquids and anisotropic fluids such as nematic...

The orientational dynamics of low molecular weight and polymeric nematic liquid crystals in a flow field is investigated, based on a nonlinear relaxation equation for the second rank alignment tensor. Various approximations are discussed: Assuming uniaxial alignment with a constant order...

For a system of noninteracting spheroidal Brownian particles a Fokker-Planck equation is derived which takes into account a hydrodynamical coupling between translational and orientational degrees of freedom. With the moment method, transport relaxation equations are obtained from which an...