AEROELASTIC STABILITY ANALYSIS OF HEATED FLEXIBLE PANEL IN SHOCK-DOMINATED FLOWS

In order to analyze the aeroelastic stability of heated flexible panel in shock-dominated flows, a systematic theoretical analysis model is established, and then test its correctness by the numerical simulation method. First of all, based on Hamilton principle and Von-Karman large deflection plate theory, the coupled partial differential governing equations are established with thermal effect based on quasi-steady thermal stress theory. Local first-order piston theory is employed in the region before and after shock waves. The Galerkin discrete method is employed to truncate the partial differential equations into a set of ordinary differential equations. The nonlinear flutter equation is linearized in the equilibrium position based on Lyapunov indirect method,and then Routh-Hurwits criterion is employed to analyze stability of the linear system. Finally, aeroelastic stability of the nonlinear flutter system is obtained. In order to verify the correctness of theoretical results, the nonlinear flutter equations are solved by the fourth-order Runge-Kutta numerical integration method to obtain time history of panel response. The results show that stability of the panel is reduced in the presence of the oblique shock. In other words, the heated panel becomes aeroelastically unstable at relatively small flight aerodynamic pressure. And the LCO amplitude and frequency are observed to increase with shock strength; the stability boundaries of heated flexible panel in shock-dominated flows are distinct from that in regular supersonic flows; only if the non-dimensional dynamic pressure upstream of the shock impingement location and the non-dimensional dynamic pressure downstream of the shock impingement location of the panel satisfy critical condition of flutter stability, will the heated panel be aeroelastically stable.