Spatial and temporal structure of coherent motion by combined simultaneous flow visualization technique of dye-streak/particle-pass line

Abstract

Relationship between simultaneous visual pattern of coherent motion and fluctuating components of u and v in the near-wall turbulent flow is investigated using Dye-Particle-Image VeIocimetry(DPIV)' technique. The results indicate that dye-streak patterns of coherent vortical motions associate with the vorticity of ωz and uv structures. DPIV technique plays an important role to understand the physics of coherent motion in the near-wall turbulence.