Spanwise vorticity structure in turbulent boundary layers

Abstract

Four-element hot-wire probe measurements are used to examine the structure of the spanwise vorticity in the inner region of low Reynolds number zero pressure gradient turbulent boundary layers. Single-probe measurements were made over the range 1010 ≤ Rθ ≤ 4850(Rθ = θU∝/ v, where θ is the momentum deficit thickness, and U∝ is the free-stream velocity), while two probe measurements were made at Rθ ≈ 1010. The present results indicate that for y + < 50 statistical moment profiles of ωz scale on inner variables. Event duration analyses indicate that a nearly logarithmic increase in inner normalized time scales of the ωz bearing motions occurs with increasing Rθ. Outside the buffer region, this ..