eng Science and Education Publishing American Journal of Energy Research 2328-7330 2025-10-29 13 3 86 95 10.12691/ajer-13-3-2 AJER20251332 article Tiberius S. Gikenyi gikenyi.tiberius@students.jkuat.ac.ke 1 Churchill O. Saoke 1 Joseph N. Kamau 1 Physics Department, Jomo Kenyatta University of Agriculture and Technology, Nairobi, 00200, Kenya The efficiency of a wind turbine depends on the aerodynamic efficiency of its blade¡¯s airfoil geometry. In this study, we numerically investigate the influence of static extended trailing edges (SETEs) and gurney flaps (GFs) on the aerodynamic characteristics of the NACA 0012 airfoil at a low Reynolds number (Re = 2 × 105). The analysis was conducted using computational fluid dynamics (CFD) based on the 2-dimensional steady and unsteady Reynolds-Averaged Navier-Stokes (RANS/URANS) with the k-¦Ø Shear Stress Transport (SST) model. Three different-sized SETE flap lengths of 10%c, 20%c, and 30%c and three Gurney flaps with heights of 1%c, 2%c, and 3%c were tested at various angles of attack (-4° to 20°). Measurements used the same baseline airfoil at the same Reynolds number to ensure direct comparison between SETE and Gurney flaps. Results show that while the GF 2%c produces high lift, it also causes greater instability beyond stall. SETE 20%c provides superior lift-to-drag ratios, delays separation, and reduces unsteady wake structures, making it an ideal configuration for small-scale wind turbine applications. https://pubs.sciepub.com/ajer/13/3/2/ajer-13-3-2.pdf NACA0012 Gurney flap Static extended trailing edge CFD low Reynolds number