A safety-factor assisted non-probabilistic reliability-based topology optimization for wings with multi-source uncertainty

Aircraft structures inevitably encounter complex situations, including material dispersion and uncertain flight conditions, during their service life. This paper focuses on the wing structure and presents a safety-factor-assisted non-probabilistic reliability-based topology optimization (SF-NRBTO) design method for uncertain optimization of wing structures. To begin, non-probabilistic uncertainty characterization is performed for non-deterministic factors such as wing structural materials and flight conditions. The uncertain aerodynamic load is then interpolated into the wing structure using a radial basis function. Uncertainty propagation analysis of the aerodynamic-structure coupling system is conducted using the vertex method to determine the bounds of both the structural and aerodynamic response. Subsequently, the reliability of the proposed scheme is evaluated based on non-probabilistic set theory. By employing the safety factor method, reliability constraints are formulated for non-probabilistic reliability-based topology optimization. This ensures that the obtained scheme outperforms the design approach based on traditional safety factors, and the underlying mechanism is explained within the provided context. Finally, the effectiveness of the proposed method is demonstrated through two numerical examples, followed by concluding remarks.