Density-induced asymmetric pair of Dean vortices and its effects on mass transfer in a curved microchannel with two-layer laminar stream

Jin Xuan, Michael K.H. Leung, Dennis Y.C. Leung, Meng Ni

Research output: Journal article publicationJournal articleAcademic researchpeer-review

17 Citations (Scopus)


To better understand the mass transfer and provide possible performance improvement methods for the microfluidic devices relying on the two-layer laminar flow, a computational fluid dynamics simulation is performed to investigate the phenomenon of a two-layer laminar stream passing through a curved microchannel. The results show that due to the density difference between the two fluids, asymmetric pair of Dean vortices are formed as the fluids pass through the curve. Due to the inter-stream convection, the denser fluid intrudes into the less-dense one resulting in a Γ sharp layer-interface. Furthermore, the parametric analysis helps identify ways to minimize the inter-stream mass transfer, such as increasing the density ratio, as well as reducing the Re number and aspect ratio. The study concludes that the microchannel curve can be properly designed to obtain a clear interface between two streams to fulfill the basic requirement of microfluidic devices.
Original languageEnglish
Pages (from-to)216-223
Number of pages8
JournalChemical Engineering Journal
Issue number1
Publication statusPublished - 15 Jun 2011


  • Computational fluid dynamics
  • Dean vortices
  • Microchannel
  • Two-layer laminar flow

ASJC Scopus subject areas

  • Chemistry(all)
  • Environmental Chemistry
  • Chemical Engineering(all)
  • Industrial and Manufacturing Engineering

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