Large-scale manipulation of a turbulent boundary layer has been obtained by using a yawed quasi- D synthetic et interacting with the mean flow. Measurements were taken by means of Digital article Image elocimetry. Images were recorded in planes perpendicular to the wall and aligned with the main flow, in planes perpendicular to the wall and to the main flow and in planes parallel to the wall. For appropriate slit orientations and forcing frequencies specific zones of the near wall region showed a reduced turbulent activity. A reduction of events detected in the region closer to the wall is observed. Moreover, ISA analysis and the correlation function computed for the longitudinal component of the velocity showed the presence of more fragmented coherent structures.
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