LAUSR

The aeroelastic stability (panel flutter) of an orthotropic composite shell in supersonic and subsonic flows of a gas over its outer and inner surfaces, respectively, is investigated. The internal two-phase flow is comprised of an air portion and a portion of mixture of air and gas. The structural damping is taken into account according to the Voigt hypothesis. The solution of corresponding equations is sought in the form of trigonometric series in the longitudinal coordinate. By the Bubnov–Galerkin method, the problem is reduced to a system of algebraic equations. The characteristic equation, obtained in an explicit form by using the Lagrange polynomial, is analyzed employing the Routh–Hurwitz criterion. Relations for the critical flow speed as functions of parameters of the internal flow are constructed.