Prediction of mixing performance of passive mixers using vortex index

Abstract

We studied the effects of vorticity and molecular diffusion on laminar mixing in passive micromixers. A micromixer is an essential component of Lab-on-a-Chip because mixing is extremely slow in a microchannel. Based on Peclet number and vortex index that is newly defined in this paper, we developed a numerical model with which we can predict mixing extend of passive micromixers. To verify the model, we performed numerical simulations for various types of passive mixer and a wide range of Peclet number and Reynolds number. The comparison of model predictions and numerical results shows a good agreement. This model helps design passive mixers for Lab-on-a-Chip and readily predicts the mixing performance.