Lattice Boltzmann Simulation of Electroosmotic Flow and Heat Transfer in a Three-dimensional Rectangular Microchannel

Electroosmotic flow and heat transfer in a three dimensional rectangular microchannel is numerically investigated using a unified lattice Boltzmann method (LBM). The potential distributions, the dimensionless velocity distributions and the temperature distributions in the section of microchannel under both Poisson-Boltzmann model and Nernst-Planck model are compared with Debye-Huckel approximate solution and analytical solution respectively to validate the accurate and precise. Furthermore, the electroosmotic flow and heat transfer in the microchannel with different nonuniform potential distribution along the wall are simulated, and the positive charge distributions for different model are compared. It is found that the Poisson-Boltzmann model has considerable limitations to describe the electric potential field, which have an obvious impact on the flow mode and convective heat transfer in the microchannel. © 2019, Science Press. All right reserved.