Near field study of vortex attenuation using wing-tip blowing

The investigation of wind-tip blowing as a form of attenuating the trailing vortex generated by a rectangular wing was discussed. The results at one semi-span downstream showed significant reductions in the tangential velocities in the vortex core with the velocity reduced to approximately 55% of the no blowing case. The diameter of the core was also increased by approximately 2-5 times and the vorticity was significantly reduced and redistributed due to the presence of blowing. A decrease in induced drag with the addition of blowing was also evident from the outboard movement of the vortex center. Axial velocity measurement showed a reversal from a rearward direction for the no blowing case to a forward direction for the blowing cases.