In this work, a reliability optimization method is proposed to resolve the multi-objective reliability-based design optimization (MORBDO) of the compressor disc with multiple correlated failure modes. The cost function-based reliability allocation model is firstly established to allocate the structural reliability into reliability under failure mode by minimizing the cost. During this process, the correlations among multi-failure modes are described by using the pair-copula function. Then, an improved MOPSO algorithm based on the niche sorting strategy and the dynamic inertia weight, is employed to solve the MORBDO problem while guaranteeing efficiency and accuracy. The proposed approach is verified by the MORBDO of the compressor disc considering low cycle fatigue (LCF), creep-fatigue (CF), and combined high and low cycle fatigue (H-LCF) failure modes. Strong non-linear positive correlations among the lifetimes of three failure modes are revealed. It is proved that ignoring the correlations among failure modes by assuming independent failure modes will result in an overly conservative reliability prediction, thus leading to redundancy of structural performance in MORBDO. Furthermore, the results proved that the improved MOPSO algorithm does not only provide a better Pareto front curve but also improves computational efficiency.

在这项工作中，提出了一种可靠性优化方法来解决具有多个相关故障模式的压缩机盘基于多目标可靠性的设计优化（MORBDO）。首先建立了基于成本函数的可靠性分配模型，通过最小化成本将结构可靠性分配给失效模式下的可靠性。在此过程中，通过使用对关联函数来描述多故障模式之间的相关性。然后，基于小生境排序策略和动态惯性权重的改进的MOPSO算法被用来解决MORBDO问题，同时又保证了效率和准确性。考虑到低循环疲劳（LCF），蠕变疲劳（CF），以及组合的高低循环疲劳（H-LCF）失效模式。揭示了三种失效模式寿命之间的强非线性正相关。事实证明，假设独立的故障模式而忽略故障模式之间的相关性，将导致可靠性预测过于保守，从而导致MORBDO中结构性能的冗余。此外，结果证明改进的MOPSO算法不仅提供了更好的Pareto前沿曲线，而且提高了计算效率。因此导致MORBDO中结构性能的冗余。此外，结果证明改进的MOPSO算法不仅提供了更好的Pareto前沿曲线，而且提高了计算效率。因此导致MORBDO中结构性能的冗余。此外，结果证明改进的MOPSO算法不仅提供了更好的Pareto前沿曲线，而且提高了计算效率。