Design optimization of active microfluidic mixer incorporating micropillar on flexible membrane

In this paper, the optimization of a new design of active microfluidic mixer incorporating micropillar for accelerating the mixing of fluids was performed. The studied microfluidic mixer consists of the microfluidic, mechanical, and electromagnetic parts. The finite element analysis is used to study the effect of input channel angle, micropillar's radius and spacing, and shape of membrane on the performance of mixer. In particular, the mixing flow rate, membrane deflection and micropillar swivel or bending were evaluated. The results show that the flow rate in the range of 3.78-3.88 A mu l/s which is almost two times of the input flow rate was obtained. The results also show that the deflection height ranging from 40 to 170 A mu m, micropillar swivel from 7A degrees to 20A degrees were obtained. Furthermore, from the comparison among the membrane shapes, it revealed that the membrane in circular shape generates higher deflection and swivel than the other membranes in square and rectangle shapes due to the uniform tensile stress distribution.