Characterization of mixing in micromixers by a test reaction: Single mixing units and mixer arrays

The mixing quality of a single mixing unit and mixer arrays having various designs was characterized. A known test reaction for mixing quality had to be optimized, since a much higher sensitivity as for the characterization o f macroscopic mixers was needed. This adapted test reaction allowed not onl y the characterization of the mixing quality but also analysis of the homog eneity of the flow distribution between parallely aligned mixing units. A c omparison of the mixing quality to those of macroscopic reference systems ( like mixing in stirred and unstirred vessels as well as to laminar and turb ulent mixing-tees) is presented. The mixing quality-volume flow dependence revealed a complex behavior, the hydrodynamic origin of which has been anal yzed.