Fatigue-based reliability for hypersonic panel post-buckling flutter via distributed NES

The post-buckling flutter of hypersonic panels in aero-thermo-acoustic environments is investigated, and a fatigue-based reliability design is proposed using distributed nonlinear energy sinks (NES). The mechanism of post-buckling flutter within the static instability region is first examined, and different NES configurations are evaluated through bifurcation analyses. Stress responses are reconstructed and processed using the rainflow counting technique to quantify fatigue damage. The results identify post-buckling flutter as the dominant source of fatigue damage and reveal a counterintuitive phenomenon: although a single NES or three NES can effectively reduce displacement amplitudes, they may increase fatigue damage by activating higher-order modes with large local curvature. Furthermore, a novel reliability design framework is developed to link stochastic switching with fatigue damage and dynamic reliability. Two-dimensional reliability regions show that five NES significantly improve fatigue life and dynamic reliability. This study provides insightful guidance for hypersonic structure design.