Management of a Stronger Wall Jet by a Streamwise Vortex with Periodic Perturbation (Effect of Periodic Perturbation on Reynolds Stress Distributions)

Abstract

To investigate effect of periodic perturbation in management of a stronger wall jet by introducing a streamwise vortex, six components of the Reynolds stress tensor were measured in the three-dimensional complex turbulent flow field. Peak distributions in Reynolds stress contour maps should be understood by considering both contributions from production and convection terms. Especially, negative spanwise velocity component enlarged by periodic perturbation plays an important role on difference in the Reynolds stress contours. Assuming meander of the introduced streamwise vortex can reasonably explain periodic perturbation effect in (vw)^^- distribution and large discrepancies in the stress-strain relation. The periodic perturbation modifies Reynolds stress field and then development process of the streamwise vortex. Interaction between the streamwise vortex and the shear layer in stronger wall jet enlarges both length and velocity scales of the large-scale eddy in the outer layer.