Abstract
In this paper, we examined mixing of various two-fluid flows in a silicon/glass microchannel based on the competition of dominant forces in a flow field, namely viscous/elastic, viscous/viscous and viscous/inertial. Experiments were performed over a range of Deborah and Reynolds numbers (0.36 < De < 278, 0.005 < Re < 24.2). Fluorescent dye and microshperes were used to characterize the flow kinematics. Employing abrupt convergent/divergent channel geometry, we achieved efficient mixing of two-dissimilar viscoelastic fluids at very low Reynolds number. Enhanced mixing was achieved through elastically induced flow instability at negligible diffusion and inertial effects (i.e. enormous Peclet and Elasticity numbers). This viscoelastic mixing was achieved over a short effective mixing length and relatively fast flow velocities.
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References
Burghelea T, Segre E, Bar-Joseph I, Groisman A, Steinberg V (2004a) Chaotic flow and efficient mixing in a microchannel with a polymer solution. Phys Rev E Stat Phys Plasmas Fluids 69:066305
Burghelea T, Segre E, Steinberg V (2004b) Mixing by polymers: experimental test of decay regime of mixing. Phys Rev Lett 92:164501
Drikakis D (1997) Bifurcation phenomena in incompressible sudden expansion flows. Phys Fluids 9:76–87
Einstein A (1956) Investigation on the theory of the Brownian bovement. Dover, New York
Gan HY, Lam YC, Nguyen NT (2006) A polymer-based device for efficient mixing of viscoelastic fluids. Appl Phys Lett 88:224103
Hawa T, Rusak Z (2001) The dynamics of a laminar flow in a symmetric channel with a sudden expansion. J Fluid Mech 436:283–320
Landau LD, Lifshitz EM (1995) Fluid mechanics. Butterworth Heinemann, Oxford
Madou MJ (2002) Fundamentals of microfabrication. The Science of Miniaturization. CRC Press, Boca Raton
Nguyen H, Boger DV (1979) The kinematics and stability of die entry flows. J Non-Newt Fluid Mech 5:353–368
Nguyen NT, Wu Z (2005) Micromixers—a review. J Micromech Microeng 15:R1–R16
Ottino JM, Wiggins S (2004) Designing optimal micromixers.Science 305:485–486
Pathak JA, Ross D, Migler KB (2004) Elastic flow instability, curved streamlines, and mixing in microfluidic flows. Phys Fluids 16:4028–4034
Rodd LE, Scott TP, Boger DV, Cooper-White JJ, McKinley GH (2004) Planar entry flow of low viscosity elastic fluids in micro-fabricated geometries. In: Proceedings of the XIVth international congress on rheolgy, NF24-1-NF24-4
Stone HA, Stroock AD, Ajdari A (2004) Engineering flows in small devices. Annu Rev Fluid Mech 36:381–411
White F (1991) Viscous fluid flow. McGraw-Hill, Boston
Wu Z, Nguyen NT, Huang X (2004) Nonlinear diffusive mixing in microchannels: theory and experiments. J Micromech Microeng 14:604–611
Acknowledgments
The authors thank Agency of Science, Technology and Research, Singapore (A*Star) for its financial support (SERC grant no. 052 101 0013). The first author gratefully acknowledges A*Star for providing him an A*Star Graduate Scholarship and supports received from its affiliated institution, the Singapore Institute of Manufacturing Technology (SIMTech). PEO powder was provided by The Dow Chemical Company. This research is protected by a US provisional patent application no. 67/701,078.
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Gan, H.Y., Lam, Y.C., Nguyen, N.T. et al. Efficient mixing of viscoelastic fluids in a microchannel at low Reynolds number. Microfluid Nanofluid 3, 101–108 (2007). https://doi.org/10.1007/s10404-006-0109-4
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DOI: https://doi.org/10.1007/s10404-006-0109-4