Aerothermal-aeroelastic two-way coupling method for hypersonic curved panel flutter

A method to compute aerothermal-aeroelastic two-way coupling for hypersonic curved panel flutter is proposed. The aero-thermo-elastic governing equations of a simply-supported two dimensional curved panel are developed based on the von Kármán geometrically non-linear theory. The Galerkin approach is used to simplify the equations into discrete forms, which are solved by the fourth-order Ronger-Kutta method. The third-order piston theory is applied to the aerodynamics. The Eckert's reference temperature method and the panel heat flux formula are used to compute the aerodynamic heat flux. Several important effects are included, namely 1) two-way coupling considering the effect of elastic deformation on aerodynamic heating and aerodynamic heating on stiffness of structure, 2) accumulation of the aerodynamic heating in real cruise, 3) arbitrary, non-uniform, in-plane and through-thickness temperature distributions, and 4) the effect of initial deformation of curved panel on the flight time to the onset of flutter. Compared with the results of aerothermal-aeroelastic one-way coupling, it is revealed that the two-way coupling which induces decrease of the flight time to the onset of flutter is more dangerous. In addition, importance should be attached to this method in actual analysis.