Microfluidics and Nanofluidics

, Volume 16, Issue 1, pp 275–286

Bubble coalescence at a microfluidic T-junction convergence: from colliding to squeezing

  • Yining Wu
  • Taotao Fu
  • Chunying Zhu
  • Youguang Ma
  • Huai Z. Li
Research Paper

DOI: 10.1007/s10404-013-1211-z

Cite this article as:
Wu, Y., Fu, T., Zhu, C. et al. Microfluid Nanofluid (2014) 16: 275. doi:10.1007/s10404-013-1211-z

Abstract

This paper aims at studying the coalescence of bubbles at a microfluidic T-junction convergence by using a high-speed digital camera and the VOF simulation. The microfluidic channels have uniform square cross-section with 400 μm wide and 400 μm deep. The responses of bubble collisions at the T-junction convergence have been investigated within a wide range of dimensionless bubble size and capillary number Ca. Colliding coalescence, squeezing coalescence, and non-coalescence were observed at the junction. The result showed that whatever for colliding coalescence or squeezing coalescence, the coalescence efficiency decreases with the increase in the two-phase superficial velocity for moderate liquid viscosities, and the transition from colliding to squeezing coalescence due to the increase in the two-phase superficial velocity enhances the coalescence of bubbles. The decrease in the bubble size for moderate liquid viscosities and the increase in the liquid viscosity are not conducive to bubble coalescence.

Keywords

CoalescenceBubble collisionInterfaceMicrofluidicsT-junction

Supplementary material

10404_2013_1211_MOESM1_ESM.docx (1.4 mb)
Supplementary material 1 (DOCX 1439 kb)

Copyright information

© Springer-Verlag Berlin Heidelberg 2013

Authors and Affiliations

  • Yining Wu
    • 1
  • Taotao Fu
    • 1
  • Chunying Zhu
    • 1
  • Youguang Ma
    • 1
  • Huai Z. Li
    • 2
  1. 1.State Key Laboratory of Chemical Engineering, School of Chemical Engineering and TechnologyTianjin UniversityTianjinPeople’s Republic of China
  2. 2.Laboratory of Reactions and Process EngineeringUniversity of Lorraine, CNRSNancy CedexFrance