Modele fenomenologiczne ośrodka ciekłokrystalicznego

Fundamental formal means have been presented of a macroscopic behaviour of liquid crystals. The structure of phenomenological hydrodynamic models has also been discussed, attention being attracted to their non-equivalence and ambiguity. This refers mainly to the relation between the Ericksen-Leslie's model and those of Lubensky and Eringen-Lee within the conservation principle of the angular momentum. The work is both a review and a comparison and constitutes an introduction into the subject ''Models of liquid crystals'' to which further study will be devoted. Electrohydrodynamic and magnetohydrodynamic models, which are developed from hydrodynamic models, will be discussed in a separate publication.