Passive Flow Control Using a Multi-Scale Approach

This study investigates the impact of Triangular Prism Texturing (TPT) elements on the turbulent boundary layer characteristics of a flat plate, specifically analyzing changes in turbulent skin friction and flow separation. The analysis is based on data collected from Particle Image Velocimetry (PIV), comparing a baseline flat plate to one modified with TPT elements with a freestream velocity of 13 m/s. Results indicate that the TPT elements significantly alter the boundary layer dynamics by reducing the velocity defect and enhancing the velocity profile's fullness near the wall. This modification leads to a reduction in turbulent skin friction, as shown by a lower shear stress across the boundary layer. Additionally, the fuller velocity profiles suggest an increased momentum near the wall, enhancing the boundary layer's resistance to adverse pressure gradients and thus reducing the likelihood of flow separation. These findings demonstrate that TPT's can effectively improve the aerodynamic efficiency of surfaces by reducing drag and preventing flow separation, making it a promising technology for applications requiring optimized flow characteristics, such as in aerospace, automotive, and wind energy sectors.