Optimization of a passive micromixer using models based on variable diffusion coefficient

Abstract

In this work a passive micromixer is designed, simulated and optimized in order to obtain fully mixed liquids at the outlet. The basic configuration is a microchannel with two inlets, three outlets, and obstacles that increase the transversal component of velocity and facilitate the mixing. The simulations are based on an improved model of diffusion coefficient that depends on local concentration and properties of each mixing liquid. The model is applied to two cases of miscible fluids: water with methanol and water with glucose solution. The simulations based on this model are used to optimize design specifications. The results are discussed in terms of velocity and concentration distribution and compared to results obtained by classic approach.