Improving mixing efficiency in laminar-flow static mixers with baffle inserts and vortex generators: A three-dimensional numerical investigation using corrugated tubes

Abstract

Static mixers are vital for continuous processes, improving product quality, reducing costs, and enhancing efficiency. This study numerically investigates the mixing performance of various geometry configurations in static mixers. A corrugated tube with baffle inserts arranged in a triangular pattern is used. These studies are carried out using the CFD COMSOL Multiphysics 6.1 software with Reynolds numbers from 10 to 300, examining the impact of vortex generators on hydrodynamic behavior. The obtained outcomes reveal that the implementation of a corrugated tube induces a proficient recirculation flow within the divergence zone, thereby augmenting mixing efficiency by three times in comparison to a straight pipe as indicated by the mixing index. Introducing a baffle configuration composed of four triangular elements yields a heightened mixing index, albeit at the cost of an elevated pressure drop. An alteration of the angle of attack to 30° leads to a notable 22.6% enhancement in the mixing index while concurrently reducing pressure drop, in contrast to the condition where β equals 0°. These findings hold valuable implications for the optimization of static mixer designs, thereby elevating their utility within laminar flow applications. The resultant benefits encompass improved product quality, diminished operational costs, and heightened process efficiency.