Publicado 6 números por año
ISSN Imprimir: 2152-5102
ISSN En Línea: 2152-5110
Indexed in
Visualization and Scaling of Coherent Eddies in Wall-Bounded Turbulent Flows at Relatively Low Reynolds Numbers
SINOPSIS
Visualization of coherent eddies in fully developed turbulent channel flows based on the scaling with characteristic variables associated with wall-bounded turbulence is performed using the results of the direct numerical simulation (DNS). DNS databases obtained by solving three-dimensional Navier-Stokes equations with different Reynolds number, based on the wall friction velocity and channel half, are employed to perform the visualization. The main objective is to assess the suitability of the characteristic variables of turbulence for direct visualization of coherent eddies in the instantaneous flow fields. Normalization variables used for turbulent statistics are examined to judge the best scaling variables of coherent eddy. The results show that the coherent eddies in fully developed turbulent channel flows is best visualized when scaled with Kolmogorov scale. The streamwise and the hairpins (loop-like) can be visualized simultaneously. The simulation results may provide an important insight to uncover behaviors of coherent eddies in turbulent flow fields.