A review on the mechanics of inertial microfluidics

Document Type : Review Paper


Department of Mechanical Engineering, School of Engineering, Vali-e-Asr University of Rafsanjan, Iran


In a number of microfluidics-based systems where the Reynolds number is in an intermediate range, both viscosity and inertia are significant, and thus, plenty of interesting effects appear including inertial motion and secondary flow. In recent years, this rapidly expanding area of science has opened a new window of possibilities for micro-particle inertial focusing in high-throughput cellular separation and physiological fluids processing. Moreover, this science is applicable in bio-particle focusing in clinical diagnostics along with widespread applications in environmental cleanup. In this review, fundamental concepts governing the mechanics and physics of inertial microfluidics are discussed. Furthermore, recent mathematical frameworks and theoretical developments that have made this science what we know today are presented in detail. Finally, a number of possible futuristic promising directions in this novel field are proposed since, despite tremendous recent progress, this mainstream technology is still a nascent area of research.


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Volume 52, Issue 1
March 2021
Pages 168-192
  • Receive Date: 11 January 2021
  • Revise Date: 21 February 2021
  • Accept Date: 21 February 2021