Numerical Analysis on the Effect of Constriction on the Mixing of Fluids in Serpentine Microchannels

Fluid mixing at micro level is a key function in microfluidic systems for the homogenization of fluid samples. Extensive work has been done by many researchers in the designing of micromixers for achieving efficient mixing. The impact of constrictions on fluid flow and mixing caused by the rectangular bend microchannel is numerically analyzed in this work. The micromixer has two aligned inlet channels and a main mixing channel which has constrictions in its rectangular bend section. Numerical analysis of mixing has been carried out for three different Reynolds number viz. 10, 30 and 60 and at two constriction values (s = 0 µm and s = 50 µm). The findings suggest that the blending efficiency of the micromixer having constriction is much better than the mixing performance exhibited by the channel having no constriction (s = 0 µm).