Development of static mixers for miscible fluids in laminar flow with the use of computational fluid dynamics (CFD)

Abstract

AbstractStatic mixers with improved performance were developed from CFD simulations in a stepwise approach. The relevant geometric features of simple mixer designs and the corresponding mixing mechanisms—laminar shear, elongational flow, and distributive mixing—were identified first. This information was used to formulate guidelines for the development of new geometries. The solid elements of the static mixer should: (a) provide restrictions to the flow; (b) deflect the flow; (c) be sequentially rotated around the flow direction to provide symmetry; (d) extend from the center of the pipe to the vicinity of the walls to avoid short‐circuiting; and (e) distribute and remix the flow. Based on these guidelines, two improved mixer designs were developed: the DS A–I mixer has a good mixing efficiency and an acceptable pressure drop; the Fins 35° mixer is more efficient and compact, but requires a larger pressure drop. Their performance indicates that their use is possible on industrial applications.