Analysis of the post-flutter aerothermoelastic characteristics of hypersonic skin panels using a CFD-based approach

The present work aims to investigate the post-flutter aerothermoelastic behaviours of the hypersonic skin panels by using the integrated aerothermoelastic analysis framework developed in this paper. The aerodynamic loading and heating are computed simultaneously by solving Reynolds-averaged Navier-Stokes equations (RANS). The structural and thermal finite element models of a hypersonic skin panel are built and solved numerically to model the structural dynamics and thermal conduction. An implicit predictor-corrector scheme is employed to address the fluid-thermal-structural interactions. The aerothermoelastic characteristics of a two-dimensional hypersonic panel obtained using both one-way and two-way coupling strategies are systematically compared and discussed. The results show that: 1) The air viscosity delays the onset of flutter significantly, albeit aggravates thermal effect on the flutter instability; 2) The buckled panel can be similarly predicted by both the one-way and two-way coupling strategies. In contrast, the two-way coupling captures shockwave/boundary layer interactions leading to high local temperature; 3) The modal transition is predicted when structural displacement feeds back into the aerothermoelastic analysis. 4) The variation of temperature gradient along the panel thickness is analogous to the time-domain displacement response as revealed by two-way coupling strategy; 5) One-way coupling predicts lower maximum Von Mises stress as compared with the two-way coupling counterpart under the conditions employed in the present study.