Low-frequency ac electro-flow-focusing microfluidic emulsification Academic Article uri icon


  • Applications of electric field, using either dc or high-frequency ac field, have shown many advantages in emulsification. We further develop this technique by a detailed study on low-frequency ac electro-flow-focusing (EFF) microfluidic emulsification. Counter-intuitively, the droplet size variation is not monotonic with the electric field, in contrary to the dc-EFF emulsification. This phenomenon originates from a relaxation oscillation of flow rate through the Taylor cone. Particularly, a continuous droplet size decrease was obtained at the voltage ramp-up stage. This emulsification process was modeled in analog to the accumulation and release of charges in an RC electric circuit with an adjustable resistor. © 2010 American Institute of Physics.

author list (cited authors)

  • He, P., Kim, H., Luo, D., Marquez, M., & Cheng, Z.

citation count

  • 32

publication date

  • April 2010