Biomedical Microdevices

, Volume 14, Issue 5, pp 849–862

Numerical and experimental characterization of a novel modular passive micromixer

Authors

  • Francesco Pennella
    • Department of Mechanical and Aerospace Engineering, Politecnico di Torino
  • Massimiliano Rossi
    • Institut für Strömungsmechanik und Aerodynamik LRT-7Universität der Bundeswehr München
  • Simone Ripandelli
    • Department of Applied Science and Technology, Politecnico di Torino
  • Marco Rasponi
    • Bioengineering Department, Politecnico di Milano
  • Francesco Mastrangelo
    • Department of Mechanical and Aerospace Engineering, Politecnico di Torino
  • Marco A. Deriu
    • Department of Mechanical and Aerospace Engineering, Politecnico di Torino
  • Luca Ridolfi
    • Department of Environmental, Land and Infrastructure Engineering, Politecnico di Torino
  • Christian J. Kähler
    • Institut für Strömungsmechanik und Aerodynamik LRT-7Universität der Bundeswehr München
    • Department of Mechanical and Aerospace Engineering, Politecnico di Torino
Article

DOI: 10.1007/s10544-012-9665-4

Cite this article as:
Pennella, F., Rossi, M., Ripandelli, S. et al. Biomed Microdevices (2012) 14: 849. doi:10.1007/s10544-012-9665-4

Abstract

This paper reports a new low-cost passive microfluidic mixer design, based on a replication of identical mixing units composed of microchannels with variable curvature (clothoid) geometry. The micromixer presents a compact and modular architecture that can be easily fabricated using a simple and reliable fabrication process. The particular clothoid-based geometry enhances the mixing by inducing transversal secondary flows and recirculation effects. The role of the relevant fluid mechanics mechanisms promoting the mixing in this geometry were analysed using computational fluid dynamics (CFD) for Reynolds numbers ranging from 1 to 110. A measure of mixing potency was quantitatively evaluated by calculating mixing efficiency, while a measure of particle dispersion was assessed through the lacunarity index. The results show that the secondary flow arrangement and recirculation effects are able to provide a mixing efficiency equal to 80 % at Reynolds number above 70. In addition, the analysis of particles distribution promotes the lacunarity as powerful tool to quantify the dispersion of fluid particles and, in turn, the overall mixing. On fabricated micromixer prototypes the microscopic-Laser-Induced-Fluorescence (μLIF) technique was applied to characterize mixing. The experimental results confirmed the mixing potency of the microdevice.

Keywords

Microfluidic mixerClothoid microchannelMicrofluidicsComputational fluid dynamicsMicroscopic-Laser-Induced-Fluorescence

Copyright information

© Springer Science+Business Media, LLC 2012