In the present research work, the 3-D flow field in the vicinity of rectangular wings is simulated and the trailing wake vortices generated are investigated using Computational Fluid Dynamics (CFD). The motivation behind the present investigations is the alleviation of vortex wake hazard. Various wing configurations have been tested in order to determine the quantitative and qualitative effects of wing geometries on vortex dynamics. Numerical simulations are run at chord-based Reynolds-number of 5.34×104. Lift distribution, vortex strength and core locations are computed and visualised at different measurement planes behind the trailing edge. Two sets of computations have been conducted up to 80 chordlength downstream the tip region. The first set is using conventional and notched geometries in order to correlate experimental and computed results, and also to validate the CFD parameters. The second set of numerical solutions concentrate on the development and testing of new wing designs, whilst keeping the validated CFD parameters. The first set of computational solutions demonstrate that the vorticity stream-function formulation combined with RNG-kε turbulence model are capable of predicting accurately steady and turbulent flows past wings. Very good agreement is obtained between the experimental and numerical results. The notched geometry is found to significantly influence the vortex location, strength, tangential and axial velocity distributions. Numerical calculations confirm as well that the tip and flap vortices generated by a notched wing remain distinct and unmerged, unlike those associated with conventional wings. Based on those results, a second set of wing geometries combining multiple extensions (triangular/ogee) associated with the original notch design is created. Numerical simulations are performed to evaluate the effectiveness of wing modifications in wake properties. Current results are promising: for all the numerical runs, the wakes of the notched-triangular/ogee wings have maximum levels of vorticity that are substantially less than those generated by the original notched wing. Numerical data clearly indicate that such a combination of geometries diffuse the concentrated energy within the wake, significantly affecting the strength and the merging process of the present vortex system.