The fibre orientation state evolution is evaluated by the fully 3D convection-dispersion equation, i.e. the Fokker-Planck equation. This is solved along various streamlines in the contraction with vane inserts so that effects of wakes and boundary layers could be studied across a jet. As an input to the fibre orientation model the turbulent flow field is solved by Computational Fluid Dynamics (CFD) with second-order closure of the turbulence model. Parameter values for the rotational dispersion coefficient of three hypotheses reported in studies are tested for an independent experimental case. After the contraction the anisotropy profile across the flow, has a variation in anisotropy value in different regions, identified as the boundary layer, the undisturbed region and wakes. The numerical result predicts these regions by comparison to the experimental result with the fully 3D approach of the fibre orientation state applied.