TY - JOUR T1 - Coupled MRT Lattice Boltzmann Study of Electrokinetic Mixing of Power-Law Fluids in Microchannels with Heterogeneous Surface Potential AU - Yang , Xuguang AU - Wang , Lei AU - Shi , Baochang JO - Advances in Applied Mathematics and Mechanics VL - 6 SP - 1478 EP - 1496 PY - 2018 DA - 2018/09 SN - 10 DO - http://doi.org/10.4208/aamm.OA-2017-0316 UR - https://global-sci.org/intro/article_detail/aamm/12719.html KW - Lattice Boltzmann method, electrokinetic mixing, non-Newtonian fluids. AB -

The electrokinetic mixing, as a powerful technique in microfluidic devices, is widely used in many applications. In this study, a more general dynamic model, which consists of Poisson equation, Nernst-Planck equation and Navier-Stokes equations, is used to describe the electrokinetic mixing of non-Newtonian fluids in microchannels. Furthermore, a coupled multiple-relaxation-time (MRT) lattice Boltzmann (LB) framework is developed to solve this complicated multi-physics transport phenomenon. In numerical simulations, we mainly consider the effects of the arrangement of nonuniform surface potentials and the power-law index on the mixing efficiency and the volumetric flow rate. Numerical results show that the mixing efficiency and the volumetric flow rate of shear-thinning fluids are higher than that of shear-thickening fluids under the same condition. It is also shown that for both types of fluids, there should be a balance between the mixing and liquid transport in electrokinetic microfluidics.