title: Size-selective separation of micro beads by utilizing secondary flow in a curved rectangular microchannel.
abstract: This paper presents a microscale benefit of a secondary flow obtained in a curved rectangular microchannel, which is generally unfavorable and negligible in conventional fluid flow. We have demonstrated the separation and sorting of micro beads by their size using secondary flow. The physical mechanism occurring in the size-selective separation was explained based on the numerical analysis of the characteristic velocity distribution on the cross-sectional plane normal to the main flow stream. The dynamic trajectories of micro beads of different sizes and materials are visualized and compared for the experimental demonstration. We also discuss the effects of both the shape uniformity of the micro beads and the inlet condition on the size-selective separation.
authors.affiliation: School of Mechanical Engineering, Pusan National University, Geumjeong-Gu, Busan 609-735, South Korea.
authors.forename: Dong Hyun
authors.initials: DH
authors.lastname: Yoon
authors.forename: Jin Bong
authors.initials: JB
authors.lastname: Ha
authors.forename: Yoen Kyung
authors.initials: YK
authors.lastname: Bahk
authors.forename: Takahiro
authors.initials: T
authors.lastname: Arakawa
authors.forename: Shuichi
authors.initials: S
authors.lastname: Shoji
authors.forename: Jeung Sang
authors.initials: JS
authors.lastname: Go