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 



The fabrication and design of the microfluidic devices were possible with the advice and assistance of S. Schlautman and H.S. Rho. The authors are grateful to G. Lajoinie for his valuable assistance during the setup preparation. We also would like to acknowledge the useful comments of Prof. J. M. Gordillo during the design phase. This work has been partially financed with a grant from the V Plan Propio de Investigación of the University of Seville, Project TEP-5984 from Consejería de Economía, Innovación, Ciencia y Empleo and NanoNextNL, a micro- and nanotechnology consortium of the Government of the Netherlands and 130 partners.


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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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