Stall Flutter Control of a Wing Section by Leading Edge Modifications

Abstract

A solution procedure is described for determining the two-dimensional and two-degrees of freedom flutter characteristics for wings at large angles of attack. This procedure requires a simultaneous integration in time of the solid and fluid equations of motion. The fluid relations of motion are the unsteady, compressible Navier-Stokes equations, solved implicitly by second-order Roe approximation scheme in a moving coordinate system. The solid equations of motion were integrated in time by use of fourth-order Runge-kutta method. In this paper, the stall flutter of a rectangular wing with section of NACA 0012 is studied. Therefore, the aeroelastic responses of system were calculated by applying mode shapes for vibrating wing. Then the obtained responses resulted from several changes in L.E. shape of wing are compared. The results showed that these different L.E. shapes cause the changes on oscillating parameters of system. In these changes, applying a camber with 25 deg angle had best result in this study.