Modeling viscoelastic flow in a multiflux static mixer

We present a numerical and experimental study of the polymer flow in a multiflux static mixer. Various geometrical configurations are compared in terms of layer homogeneity. To evaluate the layer-forming process in different geometries, we applied a general and precise approach based on trajectory calculations for a large set of material points, followed by a statistical analysis. A simulation of viscous flow using the Carreau-Yasuda constitutive equation produced results which deviated from our experimental findings. Therefore, we used the Giesekus constitutive equation, taking into account viscoelastic effects, such as extrudate swell and secondary motions inside the mixer. Parallel plate rheometry was employed to collect dynamic mechanical data in the linear viscoelastic flow regime. Weissenberg numbers were calculated, and the maximum relaxation time in the obtained spectrum was limited to avoid divergence issues. The results of our study provide deeper insights into the layer-forming process of viscoelastic melts in a multiflux static mixer.