A double-layer sequential efficient algorithm for multidisciplinary optimization of hypersonic aircraft hot structures

The hot structure of hypersonic aircraft operates in a complex service environment. During the structural design process, employing a multi-disciplinary fine optimization design method that considers multi-field coupling can ensure the superior performance and reliability of the aircraft structure under various complex operating conditions. To address the issues of low efficiency and convergence challenges associated with traditional multi-disciplinary optimization algorithms and reliability optimization algorithms, this paper proposes a double-layer sequential optimization algorithm designed specifically for multi-disciplinary reliability optimization of aircraft structures. By decomposing the multi-disciplinary optimization into a primary optimization problem and several subordinate optimization problems associated with individual constraints, the algorithm achieves decoupling of the constraints within the multi-disciplinary optimization framework, thereby enhancing optimization efficiency and significantly mitigating the substantial computational cost incurred by multi-disciplinary coupling analysis during the design optimization process. Subsequently, reliability optimization is performed on the multidisciplinary optimal design points. By employing a double-layer nesting method, deterministic optimization is decoupled from reliability analysis, greatly enhancing the efficiency of reliability optimization. The two-layer sequential optimization algorithm extends multidisciplinary optimization into the realm of aircraft structural reliability optimization, not only expediting the optimization process but also enhancing the practicality and efficacy of the design. Finally, a case study on the optimization of hypersonic airfoil structures is presented to validate the validity of the proposed method and the enhancement in optimization efficiency of multidisciplinary reliability-based design for aircraft structures.