Inspired by nature, experiments on the aerodynamic behavior of wings and wind  turbines with sinusoidal leading-edge continued over the last two decades. The  studies showed promising results at post-stall flow regimes as tubercles cause a  more gradual lift loss and a higher stall angle of attack. This study aims to  investigate numerically the dependence of the wing's aerodynamic coefficients  on the tubercle's wavelength and amplitude at the stall angle of attack and 3D flow  regime. The results show that increasing the tubercle's average amplitude up to  0.02 of the average chord increases the lift coefficient by 23.61% and decreases  the drag coefficient by 4.61%. Similarly, decreasing the wavelength especially up  to 1.1096 of the average chord increases the lift coefficient up to 21.55% and  decreases the drag coefficient by 9.50%. Flow visualization shows that zones of  attaching and separation flow form on the suction surface of the scalloped wings 23 whereas the baseline wing is in a deep stall.