SEP-MRS: Synchronous enhanced PCE combining moving regression strategy for multi-objective reliability evaluation of aerospace structural systems

To improve the problem of insufficient multi-objective reliability evaluating accuracy and efficiency of aerospace structural systems, the synchronous enhanced polynomial chaos expansions combining moving regression strategy (SEP-MRS, short for) is presented based on the matrix analytical theory, moving regression strategy, polynomial chaos expansions (PCE), Bayesian optimization technique, and Copula thought. In this approach, the matrix analytical thought is utilized to synchronously establish a multi-objective output response model; the moving regression strategy is applied to select effective training samples for local approximation; the PCE is employed as a basis function for capturing global features; the Copula thought is used to construct the correlation multi-objective reliability evaluation model. Besides, the multi-objective benchmark function, engine exhaust gas temperature, and turbine blade multi-failures are served as numerical and engineering cases to validate effectiveness of the developed SEP-MRS method. The results demonstrate that the SEP-MRS method has certain advantages in modeling characteristics (i.e., modeling efficiency and accuracy) and reliability evaluation performances (i.e., evaluation efficiency and precision) by comparing various approaches. The contribution of this paper is to provide powerful theoretical guidance for the long-life and high-reliability design of aerospace structural systems.