Evaluation of a novel oscillatory flow flexible chamber mixer

Abstract

This thesis describes experiments used to evaluate the performance of a novel oscillatory flow mixer consisting of a pair of flexible chambers connected by perforated plates, or septa. During operation, the septa undergo reciprocating motion, alternately compressing the end chambers. During compression, fluid is forced through the septa, creating an array of jets that drive the mixing process. Flow and mixing characterization within the mixer were conducted using particle image velocimetry (PIV), laser induced fluorescence (LIF), and other qualitative methods. Tests were performed for Reynolds numbers (based on septum-hole diameter and through-hole velocity) ranging from 4 to 23000, which encompass the creeping, laminar, and turbulent flow regimes. Results include mean and RMS velocity, shear rate maps, concentration profiles, and qualitative observations. The results suggest that the mixer is capable of gentle, continuous stirring (important for biological applications), as well as vigorous agitation. Finally, a comparison between this mixer and other existing mixing technologies is presented, along with recommendations for mixing performance optimization for real world applications.