Abstract
A physical meaning of dye streak pattern in near wall turbulence is investigated by using of flow visualization technique DPTV (Dye streak pattern Particle Tracking Velocimetry). The structures of low speed streaks and transverse vortices in the near-wall region depend on 2D high shear region which consists of du/dy and dv/dx. Dye streak patterns in the longitudinal cross-section correspond with the high shear region. These high shear regions intersect at about right angles each other in the near wall turbulence.
