Mixing enhancement in compressible base flows via generation of streamwise vorticity

The effects of adding streamwise vorticity to the boudary layer of an axisymmetric afterbody on the development of the near-wake region was demonstrated. The addition was done through the use of delta-shaped tabs mounted on the afterbody. The tabs generated streamwise vorticity persisted through the base corner expansion and into the near wake, increasing mixing and base drag. The streamwise structure was destablized by the reattachment process, and there was no trace of these structures in the end-view images.