Influence of Groove Structures on Flow Field and Bacterial Adhesion: A CFD-DEM Coupling Study

Stringent cleanliness standards govern process fluid transport in integrated circuit (IC) manufacturing. Cavitation-induced surface defects on flow control components promote bacterial adhesion, thereby compromising wafer fabrication. To elucidate the coupling mechanisms among surface topography, hydrodynamics, and bacterial retention, this study utilizes a one-way coupled Computational Fluid Dynamics and Discrete Element Method (CFD-DEM) approach integrated with extended Derjaguin–Landau–Verwey–Overbeek (XDLVO) theory. We constructed a numerical model of rod-shaped Pseudomonas aeruginosa, integrated with a customized API-based coupling scheme to resolve temporal scale disparities, and systematically simulated flow evolution and adhesion behaviors across varying groove geometries (quadrilateral, triangular, and semicircular) and inlet velocities (1–3 m/s). The results indicate that groove-induced flow separation and recirculation vortices drive bacterial accumulation at the trailing edge. Triangular profiles exhibited superior flow stability, yielding significantly lower adhesion than quadrilateral and semicircular shapes. Bacterial retention scaled inversely with flow velocity due to enhanced hydrodynamic shear. These findings provide theoretical and engineering insights for the anti-contamination design of ultra-clean flow control components in IC manufacturing.