Generation of perturbations by a localized vibrator in the boundary layer of a nonswept wing

Artikel i vetenskaplig tidskrift, 2001

Origination and development of perturbations generated by a three-dimensional vibrating surface in the boundary layer on an airfoil with a zero sweep angle is experimentally studied. Surface vibrations were generated by a three-dimensional membrane. It is shown that high-amplitude vibrations of a three-dimensional surface lead to simultaneous formation of two types of perturbations in the boundary layer: quasi-stationary streamwise structures and wave packets accompanying them. The presence of regions with favourable and adverse pressure gradients does not exert a significant effect on evolution of streamwise structures but leads first to attenuation and then to amplification of wave packets.