Transactions of the Korean Society of Mechanical Engineers B (대한기계학회논문집B)

The Korean Society of Mechanical Engineers (대한기계학회)
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Generation of Fine Droplets in a Simple Microchannel

유체 소자를 이용한 미세 액적 생성

  • Kim, Su-Dong (School of Mechanical and Aerospace Engineering, and Institute of Advanced Machinery and Design, Seoul Nat'l Univ.) ;
  • Kim, Young-Won (BK21 School for Creative Engineering Design of Next Generation Mechanical and Aerospace Systems, Seoul Nat'l Univ.) ;
  • Yoo, Jung-Yul (School of Mechanical and Aerospace Engineering, and Institute of Advanced Machinery and Design, Seoul Nat'l Univ.)
  • 김수동 (서울대학교 기계항공공학부 및 정밀기계설계공동연구소) ;
  • 김영원 (서울대학교 차세대기계항공시스템 창의설계인력양성사업단) ;
  • 유정열 (서울대학교 기계항공공학부 및 정밀기계설계공동연구소)
  • Received : 2008.12.29
  • Accepted : 2010.06.01
  • Published : 2010.07.01
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Abstract

In the present study, we designed a microfluidic platform for generating monodisperse droplets with diameters ranging from hundreds of nanometers to several micrometers. To generate fine droplets, T-junction and flow-focusing geometry are integrated into the microfluidic channel. Relatively large aqueous droplets are generated at the upstream T-junction and transported to the flow-focusing geometry, where each droplet is broken into smaller droplets of the desired size by the action of pressure and viscous stress. In this configuration, the flow rate of the inner fluid can be made very low, and the ratio of the inner- and outer-fluid flow rates in the flow-focusing region can be made very high. It has been shown that the present microfluidic device can generate droplets with diameters of approximately $1\;{\mu}m$ (standard deviation: <3%).

본 연구에서는 직경이 수백 nm로부터 수 ${\mu}m$에 이르는 균일한 크기의 액적을 생성하는 마이크로 플루이딕 플랫폼이 설계되었다. 미세한 액적을 생성하기 위하여 T-정션과 유동집속 장치가 마이크로�a푸이딕 채널로 통합되었다. 상대적으로 큰 수성 액적들이 상류의 T-정션에서 생성되어 유동집속 장치로 이송되는데, 여기에서 각각의 액적은 압력과 점성응력의 작용에 의하여 목표로 하는 크기로 잘게 쪼개진다. 이러한 구성은 내부 유체의 매우 느린 유량과 유동집속 영역에서 내부 및 외부 유체 사이의 높은 유량비를 가능하게 한다. 본 마이크로플루이딕 장치는 약 $1\;{\mu}m$ 크기의 직경을 가지는 액적들을 3%보다 작은 표준 편차로 생성할 수 있음이 제시되었다.

Keywords

References

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