Piv study of the influence of large-scale streamwise vortices on a turbulent boundary layer

• Published in: Experiments in fluids Vol. 33; no. 5; pp. 663 - 669
• Main Authors: DI CICCA, G. M, LUSO, G, SPAZZINI, P. G, ONORATO, M
• Format: Journal Article
• Language: English
• Published: Heidelberg Springer 01.11.2002; Berlin
• Subjects: Boundary layer and shear turbulence; Exact sciences and technology; Fluid dynamics; Fundamental areas of phenomenology (including applications); Instrumentation for fluid dynamics; Physics; Turbulent flows, convection, and heat transfer; Test facilities; Turbulent flow; Vorticity; Vortex generator; Measuring methods; Particle image velocimetry; Large scale; Experimental study; Velocity measurement; Boundary layers
• ISSN: 0723-4864; 1432-1114
• DOI: 10.1007/s00348-002-0510-z

Vortex generator jets were used to generate large-scale longitudinal vortices embedded in a flat-plate turbulent boundary layer. The investigation was performed in a water tunnel, measuring instantaneous flow fields in planes parallel and normal to the flat plate, using particle image velocimetry. The objective of the research was to observe the response of near-wall turbulence to the imposed perturbing flow. It was shown that a small-amplitude forcing vortical flow had a significant influence on the mean and fluctuating velocity profiles. Moreover, particle image velocimetry permitted speculation upon the behavior of the wall velocity streaks under the action of the perturbing forcing vortical flow. (Author)