An experimental study on turbulent-stripe structure in transitional channel flow

Abstract

Turbulent stripe, which would occur in turbulent channel flows at transitional Reynolds numbers, was studied experimentally by flow visualization using reflective flake particles. In a range of bulk mean Reynolds number Re = 1700-2000, the turbulent stripe was observed to be inclined at angles of 20-30 degree against the streamwise direction, and its streamwise wave length was about 60 times of the channel half width ($\delta$). The longitudinal streaks with the spanwise spacing of 1.6$\delta$ were found in the quasi-laminar regions. The critical Reynolds number was Re = 1300. Time traces of the streamwise velocity were measured by laser Doppler velocimetry, revealing similarity to the equilibrium turbulent puff in the transitional pipe flow.

11 pages, 6 figures: A revised and expanded version of a paper that was presented with the same title by S. Hashimoto, A. Hasobe, T. Tsukahara, Y. Kawaguchi, and H. Kawamura, at the Sixth International Symposium on Turbulence, Heat and Mass Transfer, Rome, Italy, 14-18 September 2009

References in corpus (1)

• Mean flow of turbulent-laminar patterns in plane Couette flow

Cited by in corpus (8)

• Turbulent-laminar patterns in plane Poiseuille flow
• The growth mechanism of turbulent bands in channel flow at low Reynolds numbers
• Structured input-output analysis of transitional wall-bounded flows
• Laminar-Turbulent Patterning in Transitional Flows
• Growth dynamics of turbulent spots in plane Couette flow
• Trigger turbulent bands directly at low Reynolds numbers in channel flow using a moving-force technique
• Linear and nonlinear optimal growth mechanisms for generating turbulent bands
• Minimal seeds for turbulent bands