1994 Volume 60 Issue 579 Pages 3822-3829
An experimental study was conducted to investigate the effects of acoustic waves on the development of the turbulent statistics of a plane mixing layer using a novel experimental technique in a towing tunnel. The mixing layers were generated downstream from a splitter plate towed in a straight long tunnel. Acoustic forcing was applied to excite the shear layer and also to induce wave resonance in the free shear layer. The mixing layer large-scale structures/turbulent statistics in the transitional regime at Rem ≈ 100 based on the momentum thickness were investigated by means of the visualization/flying hot-wire technique. We found that turbulent quantities of the spanwise velocity component were homogenized and reduced because of the subharmonic resonance. These results are close to the observations of simulated mixing layers at Rem=112.