Study on mixing performance of perforation static mixers applied to high viscosity polymer mixing

To investigate the effect of perforation structure on the mixing performance, three kinds of perforation arrangement were used to modify Kenics static mixer, which were radial arrangement, axial arrangement, and diagonal arrangement. The corresponding modified static mixers were constructed and named PSM-R, PSM-A, and PSM-D. The flow of polymer melts inside them were simulated using Polyflow software. The effects of perforation arrangement, perforation diameter (d), and perforation spacing distance (δ) on segregation scale (S) and pressure drop (Δp) were analyzed using single-factor experiment. The results showed that the perforation structure was helpful to improve the mixing effect. The impact of d on S and Δp was more significant. While increasing d of PSMs, S firstly decreased and then increased. However, Δp monotonously decreased. The impact of δ on S and Δp was smaller. The model of Reynolds number (Re) versus Δp was obtained by fitting and the effect of Re on Δp was significant. In all PSMs, PSM-A with d of 3 mm and δ of 7 mm has the smallest S, that was reduced by 26.2%, compared to the standard Kenics static mixer.