Numerical simulations of mixing in an SMRX static mixer

The present work focuses on the flow characteristics and mixing induced by Sulzer SMRX static mixers. It is observed both experimentally and numerically that pressure drop increases linearly with velocity for this mixer type and that, as expected, this effect is amplified when multiple mixers are placed in the flow field. It is further shown numerically that the slope of the pressure drop versus velocity curve increases for increasing internal mixer tube crossing angles. Moreover, it is found that mixing efficiency is a strong function of the internal tube crossing angle. Finally, analysis of the pressure drop results, particle patterns at the reactor outlet, streamlines, and the intensity of segregation suggests that the optimum configuration of an SMRX mixer is one with a 90° internal tube crossing angle. It also shows to what extent the use of two static mixers provide enhanced mixing compared to one.