Abstract
Understanding the vortex dynamics in polymer solutions is one of keys for the flow control in a wide range of polymer-related material processing applications. Vortex is generated due to the viscoelasticity of polymer solution, even if no vortex formation is expected under Newtonian flow conditions. In addition, the chaotic vortices generated in viscoelastic fluids have been recently exploited to mix different fluid streams in microfluidic devices. Herein, we investigated the vortex dynamics in dilute polyethylene oxide) solutions at the junction region of Y-shaped microchannels, which have been frequently used to mix two fluid streams. We report the formation of two types of vortices: A vortex at the stagnation point of the junction (center) and a lip vortex at the upstream of the sharp corner. Fluorescent microscopy revealed that the vortex dynamics was significantly affected by the angle between the two upstream channels, polymer concentration, and flow rate. We expect that this work will be useful for understanding the viscoelastic flow in microchannels and for the future design of microfluidic devices such as microfluidic mixers.
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References
Bird, R.B., R.C. Armstrong, and O. Hassager, 1987, Dynamics of Polymeric Liquids, Wiley Interscience, New York.
Di Carlo, D., 2009, Inertial microfluidics, Lab Chip9, 3038–3046.
Engler, M., N. Kockmann, T. Kiefer, and P. Woias, 2004, Numerical and experimental investigations on liquid mixing in static micromixers, Chem. Eng. J.101, 315–322.
Hong, S.O., J.J. Cooper-White, and J.M. Kim, 2016, Inertio-elastic mixing in a straight microchannel with side wells, Appl. Phys. Lett.108, 014103.
Kang, K, S.S. Lee, K. Hyun, S.J. Lee, and J.M. Kim, 2013, DNA-based highly tunable particle focuser, Nat. Commun. 4, 2567.
Kim, D.Y. and J.M. Kim, 2019, Vortex Generation by the Viscoelastic Sheath Flow in a Flow Focusing MicroChannel, Korean J. Chem. Eng.36, 837–842.
Kim, J., S.O. Hong, T.S. Shim, and J.M. Kim, 2017, Inertio-elastic flow instabilities in a 90° bent microchannel, Soft Matter13, 5656–5664.
Kim, J.M., C. Kim., J.H. Kim, C. Chung, K.H. Ahn, and S.J. Lee, 2005, High-resolution finite element simulation of 4:1 planar contraction flow of viscoelastic fluid, J. Non-Newton. Fluid Mech.129, 23–37.
Nguyen, N.-T. and Z. Wu, 2004, Micromixers-a review, J. Micromech. Microeng.15, R1–R16.
Pakdel, P. and G.H. McKinley, 1996, Elastic instability and curved streamlines, Phys. Rev. Lett.77, 2459–2462.
Poole, R.J., S.J. Haward, and M.A. Alves, 2014, Symmetry-breaking bifurcations in T-channel flows: effects of fluid viscoelasticity, Procedia Eng.79, 28–34.
Rodd, L.E., T.P. Scott, D.V. Boger, J.J. Cooper-White, and G.H. McKinley, 2005, The inertio-elastic planar entry flow of low-viscosity elastic fluids in micro-fabricated geometries, J. Non-Newton. Fluid Mech.129, 1–22.
Soulages, J., M.S.N. Oliveira, P.C. Sousa, M.A. Alves, and G.H. McKinley, 2009, Investigating the stability of viscoelastic stagnation flows in T-shaped microchannels, J. Non-Newton. Fluid Mech.163, 9–24.
Squires, T.M. and S.R. Quake, 2005, Microfluidics: Fluid physics at the nanoliter scale, Rev. Mod. Phys.77, 977.
Tabeling, P., 2006, Introduction to Microfluidics, Oxford University Press, New York.
Tirtaatmadja, V., G.H. McKinley, and J.J. Cooper-White, 2006, Drop formation and breakup of low viscosity elastic fluids: Effects of molecular weight and concentration, Phys. Fluids18, 043101.
Xia, Y and G.M. Whitesides, 1998, Soft lithography, Angew. Chem. Int. Ed.37, 550–575.
Yang, S., J.Y. Kim, S.J. Lee, S.S. Lee, and J.M. Kim, 2011, Sheathless elasto-inertial particle focusing and continuous separation in a straight rectangular microchannel, Lab Chip11, 266–273.
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This research was supported by the Ajou University Research Fund.
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This paper is based on an invited lecture presented by the corresponding author at the 30th Anniversary Symposium of the Korean Society of Rheology (The 18th International Symposium on Applied Rheology (ISAR)), held on May 21-24, 2019, Seoul.
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Park, YM., Hong, S.O., Lee, P.C. et al. Vortex dynamics at the junction of Y-shaped microchannels in dilute polymer solutions. Korea-Aust. Rheol. J. 31, 189–194 (2019). https://doi.org/10.1007/s13367-019-0019-0
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DOI: https://doi.org/10.1007/s13367-019-0019-0