Effects of surface roughness and electrokinetic heterogeneity on electroosmotic flow in microchannel
Author(s): Masilamani K, Ganguly S, Feichtinger C, Bartuschat D, Rüde U
Publisher: Institute of Physics
Publication year: 2015
Journal issue: 035505
Pages range: 1-19
In this paper, a hybrid lattice-Boltzmann and finite-difference (LB-FD) model is applied to simulate the effects of three-dimensional surface roughness and electrokinetic heterogeneity on electroosmotic flow (EOF) in a microchannel. The lattice-Boltzmann (LB) method has been employed to obtain the flow field and a finite-difference (FD) method is used to solve the Poisson-Boltzmann (PB) equation for the electrostatic potential distribution. Numerical simulation of flow through a square cross-section microchannel with designed roughness is conducted and the results are critically analysed. The effects of surface heterogeneity on the electroosmotic transport are investigated for different roughness height, width, roughness interval spacing, and roughness surface potential. Numerical simulations reveal that the presence of surface roughness changes the nature of electroosmotic transport through the microchannel. It is found that the electroosmotic velocity decreases with the increase in roughness height and the velocity profile becomes asymmetric. For the same height of the roughness elements, the EOF velocity rises with the increase in roughness width. For the heterogeneously charged rough channel, the velocity profile shows a distinct deviation from the conventional plug-like flow pattern. The simulation results also indicate locally induced flow vortices which can be utilized to enhance the flow and mixing within the microchannel. The present study has important implications towards electrokinetic flow control in the microchannel, and can provide an efficient way to design a microfluidic system of practical interest.
FAU Authors / FAU Editors How to cite
APA: Masilamani, K., Ganguly, S., Feichtinger, C., Bartuschat, D., & Rüde, U. (2015). Effects of surface roughness and electrokinetic heterogeneity on electroosmotic flow in microchannel. Fluid Dynamics Research, 47(035505), 1-19. https://dx.doi.org/10.1088/0169-5983/47/3/035505
MLA: Masilamani, Kannan, et al. "Effects of surface roughness and electrokinetic heterogeneity on electroosmotic flow in microchannel." Fluid Dynamics Research 47.035505 (2015): 1-19.