Dynamic streaming birefringence

Summary A compact formulation is given of the phenomenon of birefringence and some results in oscillatory deformation are derived in terms of a birefringence tensor. The birefringence tensor then enables invariant forms of rheo-optic equations to be formulated involving a birefringence relaxation spectrum. An important practical aspect of the work is that the use of streaming birefringence in engineering studies of inhomogeneous or unsteady fluid flow fields is rather more complicated than the use of photoelastic effects in the study of deformed solids.