The Distributed-Suction Effect on the Development of Disturbances at the Nonlinear Stage of Their Evolution in the Boundary Layer

Abstract

The results of experimental investigations into the effect of distributed suction through a finely perforated permeable section on the spatial development of disturbances at the nonlinear stage of their evolution in the boundary layer of a straight wing are presented. It is shown that distributed suction makes possible reducing the intensity of both natural pulsations of the boundary-layer velocity and artificial ones generated by an external acoustic field at the fundamental frequency and its harmonics by two orders of magnitude. Affecting significantly the average flow, suction rules out the turbulent state of the boundary layer below the impact area and shifts the flow separation keeping it in the laminar state.