A theoretical investigation of the Pieranski—Guyon instability in Couette flow of nematic liquid crystals

Abstract

This paper examines the onset of homogeneous and roll type instabilities in Couette flow of a nematic liquid crystal with the anisotropic axis of these transversely isotropic liquids uniformly aligned in the axial direction. The stabilising influence of an axially oriented magnetic field is also considered Within the context of a linear stability analysis, an orthonormalisation method is employed to compute accurate numerical results from the continuum equations for the critical shear rates at which instability becomes possible. The dependance of the thresholds upon magnetic field strength is investigated leading to a prediction of the value at which a change in the nature of the instability occurs. The influence of superposed rotation upon this transition value is also examined.