SPECTRAL DYNAMIC STIFFNESS METHOD FOR THE FLUTTER PROBLEM OF COMBINED PLATES

At present time, the spectral dynamic stiffness method is being actively developed as an alternative to finite element for vibration and stability problems of composite structures from beams, rods, plates shells. This approach, based on exact solutions governing differential equations, makes it possible more effectively study problem in medium high frequency ranges, gives analytical expressions natural modes. It proposed use advantages this flutter orthotropic plate a supersonic gas flow. Using linear approximation piston theory, solution investigated according Galerkin basis eigenforms vacuum. According approach boundary value reduced homogeneous infinite algebraic system equations with coefficients are depending physical-mechanical geometrical parameters problem. The parameter included linearly, that allows us reduce eigenproblem determining eigenvalues vectors matrix. convergence number functions studied numerically. shown first 16 provide good method. Examples numerical implementation given, obtained allow dependence critical velocity properties material geometry combined plate.