On the Aeroelastic Stability of Orthotropic Panels in Supersonic Flow

Abstract

An investigation is made of the aeroeiastic stability of thin, orthotropic wings and panels of low aspect ratio. The configurations analyzed here are simply supported along two spanwise edges but have free leading and trailing edges. The mathematical model is obtained using classical plate theory and a two term binomial expansion of piston theory. The application of the boundary conditions gives rise to a complex eigenvalue problem which is thoroughly analyzed. An exact solution for the critical speeds is derived. I t is shown that the flutter speed can be closely approximated by a simple expression which also permits the evaluation of the effects of the pertinent design parameters. I t is also shown that the flutter speed of an orthotropic wing may be closely approximated by that of an isotropic wing with a different aspect ratio. The present investigation also extends the existing work of flutter of panels tha t are simply supported along all four edges to the orthotropic case.