Fluid modeling in low Reynolds number systems

Abstract: Recent years have seen a tremendous increase in the level of research efforts targeted towards the use of microfluidic devices in medicine, biology, and chemistry. The applications of such systems range from chemical synthesis and analysis, to enabling tools for biotechnology, such as DNA or protein analysis and drug discovery. The benefits of replacing “macro” fluid handling systems include the reduction in the consumption of samples and reagents; the enhanced performance in the reactions’ speed due to increased surface to volume ratios; and the increased portability associated with the integration of various analytical processes within small areas. One of the fundamental challenges in the development of microfluidic devices is enhancing the mixing of the reactant flows needed as part of their functionality. The flow structures on the microscale are laminar with parallel streamlines and no turbulence. This greatly limits the convectional mixing, and forces microfluidic devices to rely on slow diffusional mixing. This talk will present some of the work done by me and my collaborators on exploiting the interaction of the flow with the confining geometry in microfluidic devices, to greatly enhance their mixing performance. Results will be presented on Dean flow curved micromixers, ridged microchannels and microfluidic fuel cells. Some of the work done on modelling fluid flow is also relevant for cavity flows and polymer processing.