Lattice Boltzmann-based microchannel concentration mixing with surface roughness-mediated flow dynamics

• DOI: 10.1063/5.0257627
• Publication Date: 2025-03-14T14:32:23Z
• Authors: Lit Kean Chai; Chin Vern Yeoh; Ean Hin Ooi; Ji Jinn Foo
• Keywords: Lattice Boltzmann methods; Microchannel

Efficient mixing at the microscales is essential for optimizing mass transfer and reaction rates in various microfluidic applications, underscoring significance of comprehending manipulating surface roughness to improve performance. Surface morphology microchannels inherently influenced by fabrication post-treatment. This study investigates effects three-dimensional (3D) Gaussian-generated random on species homogenization. Nine profiles, varying (a) relative (ε = 0.4%, 0.7%, 1.0%) (b) correlation length (k 10%, 20%, 30%), form channel base ReDh 100. Using lattice Boltzmann method, we examine efficiency (MI), velocity statistics, spatial frequency. Higher ε enhances near-wall mixing, with a 5.7% MI increase 1.0% compared 0.4%. Conversely, shorter lengths create more rugged surfaces, increasing interfacial area diffusion thereby elevating 8.4% when k decreases from 30% 10%. Spatial frequency analysis confirms that higher frequencies (shorter wavelengths, lower k) near-surface mixing. However, smoother surfaces (higher reduce global flow resistance, enhance central advective effects, overall outlet Thus, practical applications emphasizing performance, yield superior results. not only advances our understanding parameters fluid rough-walled highlights characteristics but also offers valuable insights into processes diverse applications.