Interval-updated inverse identification framework for transient coupling of loads and heat fluxes via force-thermal modal decomposition and adaptive surrogate modeling

Nowadays, the working conditions of aircraft structures, especially those of hypersonic aircraft, are becoming increasingly complex and extreme. These structures are subjected to harsh environments of mechanical and significant thermal loads generated by aerodynamic loads. To enhance efficiency of load design, improve structural safety, and carry out structural health monitoring, a reliable mechanical-thermal load identification method is urgently needed. This paper proposes a load identification approach based on piecewise response surface models (RSMs). The method reconstructs structural responses using RSMs and converts the problem of load identification to optimization problems. Furthermore, multi-source uncertainty analysis is conducted based on explicit mathematical expressions of surrogate models. A dynamic sampling strategy based on spacing among data points is also introduced to improve computational efficiency. Finally, numerical examples are presented to validate the proposed method, and the influence of key parameters is also investigated.