Monodisperse droplets by impinging flow-focusing Academic Article uri icon


  • © 2017, Springer-Verlag GmbH Germany. We proposed a new flow-focusing technique for generation of monodisperse femtoliter droplets, based on the capillary micro-cross. A funnel-shaped interface of two phase system is observed in a capillary cross for mass production of uniform drops, where a tapered exit orifice is extruded into the dispersed feeding capillary. The droplets, down to 2 μm in size at frequency of 20 kHz, are controllable in size when choosing orifice and capillary sizes, as well as flow rates of inner and outer fluids. For a specific diameter of exit orifice, there is a maximal flow rate of outer fluid, beyond which the interface will be penetrated. Until then, the interface is in steady state and all droplets are highly uniform (<3%), implicating an absolute instability in the whole process.

author list (cited authors)

  • Wu, T., Luo, Z., Ding, W., Cheng, Z., & He, L.

citation count

  • 7

publication date

  • August 2017