Thermal flutter scaling laws for supersonic small-aspect-ratio wings and scaled models design

The influence of the thermal environment on flight cannot be ignored, as it leads to a degradation of material properties and thermal stress that can exacerbate thermal flutter. However, challenges remain in using scaled wind tunnel models to make accurate predictions for full-scale models in high-speed thermal environments, with the results relying heavily on the accuracy of scaling laws. Here, the effects of uniform/non-uniform temperature fields and boundary conditions on thermal stress are analyzed, and the effects of thermal stress and reductions in the Young’s modulus on thermal flutter are determined. For a wing with a clamped root, the influence of thermal stress on the flutter result is more significant. The influence of a non-uniform temperature field on the flutter result is significantly greater than that of a uniform temperature field. Furthermore, the thermal flutter scaling law, considering thermal stress, is derived for supersonic small-aspect-ratio wings with shell elements, and the design process for the scaled model is presented. The scaled models for Case A and Case B were designed from the perspectives of neglecting and incorporating qualitative similarity in thermal stress, respectively. Several examples demonstrate that the design approach for scaled models is not unique, allowing for different structural configurations and material selections to meet various design requirements. Finally, fluid-structure-thermal coupling calculations are carried out for Case B and the scaled model Case B-2 to simulate thermal flutter as the temperature gradually increases during flight. It is found that the scaled model can accurately reflect the thermal flutter characteristics of the full-scale model during the flight process.