Study of the geometry in a 3D flow-focusing device

  • Elena Castro-Hernández
  • Maarten P. Kok
  • Michel Versluis
  • David Fernandez Rivas
Research Paper


We present a numerical and experimental study on a non-planar three-dimensional design of a microfluidic flow-focusing device for the well-controlled generation of monodisperse micron-sized droplets. Three relevant geometric parameters were identified: the distance between the inner inlet channel and the outlet channel, the width of the outlet channel, and its length. Simulation data extracted from a full parameter study and finite element simulations yielded four optimum designs that were then fabricated using soft lithography techniques. Under the predicted operating conditions, micro-droplets of a size of \({\sim}1\,\upmu \text {m}\) in diameter are obtained from a channel \(50\,\upmu \text {m}\) in width. This work represents an important breakthrough in the practical use of flow-focusing devices delivering a ratio of constriction to droplet size of 50 times, with the advantage of reduced clogging of the micro-channel, greatly improving the control and reliability of the device.


Flow-focusing Microfluidics Jet Micro-droplets 


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Copyright information

© Springer-Verlag Berlin Heidelberg 2016

Authors and Affiliations

  • Elena Castro-Hernández
    • 1
  • Maarten P. Kok
    • 2
  • Michel Versluis
    • 2
  • David Fernandez Rivas
    • 3
  1. 1.Área de Mecánica de Fluidos, Departamento de Ingeniería Aeroespacial y Mecánica de FluidosUniversidad de SevillaSevilleSpain
  2. 2.Physics of Fluids GroupMESA+ Institute of Nanotechnology, University of TwenteEnschedeThe Netherlands
  3. 3.Mesoscale Chemical SystemsMESA+ Institute of Nanotechnology, University of TwenteEnschedeThe Netherlands

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