2003/12/01 by Y. HOARAU, Yannick Hoarau, M. BRAZA +7 · 1 citation
Engineering · Environmental Science · #Fluid Dynamics and Turbulent Flows #Wind and Air Flow Studies #Fluid Dynamics and Vibration Analysis
paper · pdf · doi:10.1017/s0022112003006530
The transition to turbulence in the incompressible flow around a NACA0012 wing at high incidence is studied by DNS in the Reynolds number range 800–10000. Two main routes are identified for the two-dimensional transition mechanisms: that to aperiodicity beyond the von Kármán mode via a period-doubling scenario and the development of a shear-layer instability, forced by the fundamental oscillation of the separation point downstream of the leading edge. The evolution of the global parameters as well as the variation law of the shear-layer instability wavelength are quantified. The history of the three-dimensional transition mechanisms from a nominally two-dimensional flow structure is identified beyond the first bifurcation, as well as the preferred spanwise wavelengths.