Active acoustic control of airfoil flutter

Using the derived exact solution to the acoustically induced unsteady potential flow of a two——dimensional thin airfoil,the mechanism of flutter suppression by active acoustic excitation,known as an extremely weak flow perturbation,is analyzed further.The parametric effect of sound source on the flutter boundary is discussed,and through the theoretical calculation of the coupled acoustic-vortex,the conducted wind-tunnel experiment is explained.The results show that the noncirculatory and circulatory parts of the acoustically induced aerodynamic loads play different roles,as the sound source is located in different position.Moreover,in the acoustic flutter suppression processl there are certain relations between the parameters of the closed-loop system,and the optimal parameter must be correctly chosen.The present investigation provides a theoretical foundation for the active acoustic control techniques applied in the aerodynamic areas