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A New Concept to Transport a Droplet on Horizontal Hydrophilic/Hydrophobic Surfaces

친수성/소수성 수평 표면상에서의 액적이송에 관한 새로운 개념

  • 명현국 (국민대학교 기계시스템공학부)
  • Received : 2013.11.18
  • Accepted : 2014.01.13
  • Published : 2014.03.01

Abstract

A fluid transport technique is a key issue for the development of microfluidic systems. In this paper, a new concept for transporting a droplet without external power sources is proposed and verified numerically. The proposed device is a heterogeneous surface which has both hydrophilic and hydrophobic horizontal surfaces. The numerical simulation to demonstrate the new concept is conducted by an in-house solution code (PowerCFD) which employs an unstructured cell-centered method based on a conservative pressure-based finite-volume method with interface capturing method (CICSAM) in a volume of fluid (VOF) scheme for phase interface capturing. It is found that the proposed concept for droplet transport shows superior performance for droplet transport in microfluidic systems.

유체이송 기술은 최근 마이크로 유체시스템 개발에서 핵심문제로 인식되고 있다. 본 논문에서는 외부동력을 사용하지 않고 액적을 이송시킬 수 있는 새로운 개념을 제안하고, 수치해석을 통해 증명하였다. 제안된 장치는 표면을 단순하게 친수성과 소수성 표면의 복합표면으로 구성하는 것이다. 새로운 개념을 입증하기 위한 수치해석은 보존적인 압력기반 유한체적방법에 기초한 비정렬 셀 중심 방법 및 VOF 방법에 체적포착법인 CICSAM을 채용하고 있는 자체개발 코드(PowerCFD)를 사용하였다. 연구결과 본 연구에서 제안된 개념이 마이크로 유체시스템에서 액적이송에 대해 우수한 성능을 나타내는 것으로 확인되었다.

Keywords

References

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Cited by

  1. Droplet Transport Mechanism on Horizontal Hydrophilic/Hydrophobic Surfaces vol.38, pp.6, 2014, https://doi.org/10.3795/KSME-B.2014.38.6.513
  2. Transport Mechanism of an Initially Spherical Droplet on a Combined Hydrophilic/Hydrophobic Surface vol.39, pp.11, 2015, https://doi.org/10.3795/KSME-B.2015.39.11.871