Three-Dimensional Vortex-Induced Reaction Hot Spots at Flow Intersections
Sang Hyun Lee, Peter K. Kang
Abstract
We show the emergence of reaction hot spots induced by three-dimensional (3D) vortices with a simple A+B→C reaction. We conduct microfluidics experiments to visualize the spatial map of the reaction rate with a chemiluminescence reaction and cross validate the results with direct numerical simulations. 3D vortices form at spiral-saddle-type stagnation points, and the 3D vortex flow topology is essential for initiating reaction hot spots. The effect of vortices on mixing and reaction becomes more vigorous for rough-walled channels, and our findings are valid over wide ranges of channel dimensions and Damköhler numbers.
Topics & Concepts
VortexSaddleSaddle pointMechanicsFlow (mathematics)Reaction rateSpiral (railway)Mixing (physics)Hot spot (computer programming)PhysicsChannel (broadcasting)Materials scienceGeometryChemistryComputer scienceMathematicsBiochemistryOperating systemCatalysisQuantum mechanicsMathematical optimizationComputer networkMathematical analysisMicrofluidic and Capillary Electrophoresis ApplicationsMicrofluidic and Bio-sensing TechnologiesFluid Dynamics and Turbulent Flows