Comparison of the Structures of a Perturbed and Unperturbed Boundary Layer of the Same Reynolds Number

The comparison of the structures of the boundary layer with and without suction of the same momentum thickness Reynolds number R_θ have been made in a turbulent boundary subjected to concentrated suction, applied through a short porous wall strip. The results indicate that, relative to σ = 0, the mean velocity collapses reasonably well but there are some discrepancies in the Reynolds stresses distributions. These discrepancies are also noted in the distributions of the anisotropy invariant tensor, skewness and flatness factors. The result would suggest that the differences are a result of the difference in the initial boundary condition, which influences the flow structures to a significant streamwise location.