EXPERIMENTAL STUDY AND MODELLING OF THE INFLUENCE OF A PERIODIC WAKE ON A LIFTING SURFACE

Superscripts Related to the interaction of the flow shed from a stalled retreating blade of helicopter rotor with the following blade and its consequence on the rotor performances, the paper presents an enpe- ~~!,~~~i~t~ rimental study in 2-D configurations of the effect produced on lifting airfoils by periodic wakes. The E,R relative to emitting or recepting airperiodic wake is generated by an upstream airfoil foil oscillating in fore and aft motion. The results St obtained show that the aerodynamic behaviour of the E at rest) interacted downstream airfoil could be theoritically approached by the more simple study of a fixed isolated airfoil submitted to simultaneous varia