BioChip Journal

, Volume 13, Issue 1, pp 53–63 | Cite as

A Minireview on Inertial Microfluidics Fundamentals: Inertial Particle Focusing and Secondary Flow

  • Aram J. ChungEmail author
Review Article


In 1961, Segre and Silberberg first reported the tubular pinch effect and numerous theoretical studies were subsequently published to explain the inertial particle migration phenomenon. Presently, as fluid mechanics meets micro- and nanotechnology, theoretical studies on intrinsic particle migration and flow phenomena associated with inertia are being experimentally tested and validated. This collective study on the fluid-particle-structure phenomena in microchannels involving fluid inertia is called, “inertial microfluidics”. Beyond theoretical studies, now inertial microfluidics has been gaining much attention from various research fields ranging from biomedicine to industry. Despite the positive contributions, there is still a lack of clear understanding of intrinsic inertial effects in microchannels. Therefore, this minireview introduces the mechanisms and underlying physics in inertial microfluidic systems with specific focuses on inertial particle migration and secondary flow, and outlines the opportunities provided by inertial microfluidics, along with an outlook on the field.


Inertial microfluidics Fluid inertia Inertial particle migration Secondary flow Inertial microfluidic physics 


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Copyright information

© The Korean BioChip Society and Springer 2019

Authors and Affiliations

  1. 1.School of Biomedical EngineeringKorea UniversitySeoulRepublic of Korea
  2. 2.Department of BioengineeringKorea UniversitySeoulRepublic of Korea
  3. 3.Department of Bio-convergence EngineeringKorea UniversitySeoulRepublic of Korea

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