Turbulence and Shear Flow Phenomena -1 First International Symposium

ISBN Print: 1-56700-135-1

THE EFFECT OF ROTATION ON THE GROWTH OF HAIRPIN VORTICES IN SHEAR FLOWS. NUMERICAL SIMULATIONS

要約

Hairpin vortices are basic flow structures of turbulent boundary layers and therefore their study is of great importance. One of the basic steps for understanding the mechanisms that govern turbulent boundary layers is to consider the evolution of a single hairpin vortex. This may contribute eventually not only to the comprehension of the hairpin creation processes and to a better understanding of turbulent boundary layers, but also to devising means for controlling boundary layer turbulence by taming hairpins. In the present study, a numerical model of an experimental setup was built. An initial disturbance was created by suction. Numerical simulations of the inception, growth and shedding of hairpin vortices in laminar rotating shear flows were compared with experimental results to validate the numerical model. In the instability region, the disturbance grows in size until it becomes a hairpin that is eventually shed, while another hairpin is being formed. The numerical results are in good agreement with the experimental results. The validated numerical model is suitable for future study of the mechanisms involved in the hairpin vortex evolution and shedding.