Aeroelastic stability and nonlinear flutter analysis of viscoelastic heated panel in shock-dominated flows

Abstract

In recent years, new composite materials, functional materials and intelligent materials have been widely used in the structural design of supersonic vehicle panels, and these new materials generally have viscoelastic properties. This paper analyzes aeroelastic stability and nonlinear flutter of a viscoelastic heated panel in shock-dominated flows by using theoretical analysis methods and numerical computations, respectively. The governing equations, based on von-Kármán large deflection theory of isotropic flat plates, are constructed with viscoelastic structural damping of Kelvin's model included. Local first-order piston theory is employed in the region before and after shock to estimate the aerodynamic loadings. The results show that the introduction of viscoelastic structural damping reduces the aeroelastic stability of the panel in shock-dominated flows. The presence of the oblique shock reduces the aeroelastic stability of the viscoelastic panel. Generally, as the viscoelastic damping or the shock strength increases, the critical flutter dynamic pressure decreases. However, at the strong shock strength, the critical flutter dynamic pressures and stability boundaries remain unchanged as the viscoelastic damping changes in a range of large viscoelastic damping coefficients. It is also found that for a flexible panel in shock-dominated flows, chaotic motion can be effectively regulated as periodic motions by the additive structural viscoelastic damping. This investigation has important theoretical and practical values in the aeroelastic design of thin panel structures of supersonic and hypersonic vehicles.