Flat Plate Flow Modification Using Tubercles: Insights from Experiments and CFD Simulations

Passive flow control using structured surfaces offers a promising approach for reducing drag in turbulent boundary layers. In this study, we investigate the effect of various bio-inspired and engineered surface patterns ,specifically tubercles, on turbulent flow characteristics over a flat plate. Large Eddy Simulations (LES) and experimental measurements in a towing tank are employed to quantify near-wall flow behavior and drag reduction across a range of Reynolds numbers.

The results demonstrate that tubercle patterns can reduce drag by up to 7 percent, primarily due to the suppression of near-wall vortical structures. A parametric study highlights the critical influence of surface geometry, spacing-to-height ratio, and alignment relative to the main flow direction. These findings advance the understanding of surface-structure interactions and support the development of scalable, energy-efficient drag reduction technologies for marine, aerospace, and industrial applications.