22nd Congress of International Council of the Aeronautical Sciences, Harrogate, UK, 28 August - 1st September, 2000
Paper ICAS 2000-7.3.3

PIV STUDY OF LONGITUDINAL VORTICES IN A TURBULENT BOUNDARY LAYER FLOW

G. M. Di Cicca
Department of Aerospace Engineering, Politecnico di Torino, Italy

Keywords: piv, wall turbulence, vortex generator jets

Digital Particle Image Velocimetry has been applied to the study of a flat plate turbulent boundary layer "manipulated" by streamwise large scale vortices. The vortical field was generated by a series of jets at 45 degrees with respect to the wall and in a plane transversal to the mean flow direction. Images in planes perpendicular and parallel to the wall were analyzed to obtain mean and turbulent velocity profiles. Results from the manipulated flow were compared to the ones from the natural boundary layer. Measurements in planes at y+»20 revealed a sensible variation of streamwise turbulence intensity but, at least for the experimented flow condition, there was no evidence of disruption of the velocity streaky pattern or differences in the velocity band spacing.

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