Flow reorganization of a spanwise non-uniform airfoil by a biomorphic wavy leading edge

Wavy leading edges (WLEs) can modify separation and vortex development, yet their interaction with the spanwise pressure gradients of non-uniform airfoils with geometric twist remains unclear. Here, a biomorphic WLE inspired by the hammerhead shark cephalofoil is applied to an MH114-based spanwise non-uniform wing to examine its influence on the pressure field and vortex structures. Six configurations combining different wave numbers and amplitudes are evaluated using steady Reynolds-averaged Navier–Stokes simulations with the shear stress transport k–ω model at Reynolds numbers of 1.07 × 106 and 1.33 × 106 over angles of attack from 0° to 15°. Because the baseline wing has non-uniform section loading, the WLE produces section-dependent rather than uniform aerodynamic changes. At low angles of attack, the response is concentrated near the wave peaks, where weaker suction peaks and smoother pressure recovery redistribute the loading. At Re = 1.33 × 106 and α = 3°, W5A2 reduces drag by 10.58%; because this reduction slightly exceeds the accompanying lift loss, the lift-to-drag ratio reaches 14.83, 1.08% above the baseline. As α increases, suction loss dominates and the wavy wings become less efficient. At α = 15°, the WLE increases the separated-area fraction but redistributes separation into localized spanwise bands, accompanied by periodic wall-shear patterns and reduced coherence of large separated vortical regions. These results show that the imposed leading-edge geometry redistributes surface pressure, reorganizes the mean flow near the wall, and alters the spatial organization of the separated flow over the twisted tapered wing.