2010

Authors

  • Peng-Ching Ho Peng-Ching Ho
  • Yit-Fatt Yap Yit-Fatt Yap
  • Nam-Trung Nguyen Nam-Trung Nguyen
  • John Chee-Kiong Chai John Chee-Kiong Chai

This paper reports the investigation on the process of thermally mediated droplet formation at a microfluidic Tjunction. The temperature field generated by an integrated heater causes changes in properties of the fluids and affects the droplet formation process. The droplet formation process is formulated in this paper as an incompressible immiscible twophase flow problem. The motion of the two-phases is strongly coupled by interfacial conditions, which are governed by the three-dimensiol vier-Stokes and the energy equations. The interface or the droplet surface is described by a rrow- band particle level-set method. The numerical solutions of the problem are obtained with finite volume method on a staggered mesh and validated with the experiment data on droplet formation in the dripping regime of a T-junction. The combined effect of the temperature-dependent viscosities and interfacial tension of the fluids results in a larger droplet at elevated temperature. The effectiveness of the penetration of temperature field induced by different heater geometries that resulted in different incremental change in droplet size over a temperature range is discussed.