inertial particle focusing and separation in a modified square-wave serpentine microchannel: a dns approach

Efficient particle focusing and separation in microfluidic systems are essential for applications in biomedical research, clinical diagnostics, and industrial processes. this study examined a modified square-wave serpentine microchannel designed to enhance particle manipulation by leveraging inertial and dean forces. a direct numerical simulation (dns) approach was used to calculate forces acting on particles, including lift, dean, and virtual mass forces, under various reynolds numbers. the computational model was validated by comparing simulated results with experimental data, showing excellent agreement. particle migration patterns were evaluated across reynolds numbers, revealing distinct regimes where particles transitioned from negligible migration to focused lines and, at high flow rates, mixing occurred. the performance of the modified microchannel was compared with classical designs, demonstrating superior particle focusing and separation efficiency. additional simulations analyzed the effects of particle size and flow conditions on separation performance, highlighting the importance of flow parameters. these findings provide a foundation for optimizing microchannel geometries and suggest the potential for incorporating non-newtonian fluids to improve performance, particularly at low reynolds numbers. this study offers new insights into particle manipulation in microfluidics and lays the groundwork for advanced designs in this field.