High-frequency vibration analysis of panels under aerothermoelastic effects in supersonic airflow by an energy finite element method

Vibration analysis of heated panels in supersonic airflow under aerothermoelastic effects has attracted wide attention, but the high-frequency vibration characteristics have not yet been thoroughly studied. A novel energy finite element method (EFEM), which can consider the aerothermoelastic effects, is proposed to investigate the high-frequency vibration response of heated panels in supersonic airflow. By separating the high-frequency response from the static or low-frequency aerothermoelastic response, a linearized high-frequency forced vibration equation is derived from the nonlinear motion equation of the panel. On this basis, the effects of in-plane and aerodynamic forces on the propagation properties of elastic waves in the panel are analyzed theoretically. By introducing these effects and the equivalent loss factors of elastic waves into EFEM theory, the energy density governing equation and the corresponding energy finite element model are established. Through numerical comparative studies, it is demonstrated that the proposed EFEM can well capture the aerothermoelastic effects and efficiently predict the high-frequency vibration response of heated panels in supersonic airflow. Particularly, the present EFEM is valid for panels in different aerothermoelastic states such as thermal buckling and flutter. In addition, the effects of aerothermoelasticity on the high-frequency vibration response are studied in detail, and the corresponding effect mechanism is revealed.