A Chebyshev interval iteration-based multidisciplinary interval reliability optimization

The inherent uncertainty of parameters poses a significant challenge to multidisciplinary design optimization (MDO), especially when sample availability is limited and computational costs are high. This paper introduces a n ovel iteration-based methodology to address the multidisciplinary interval reliability optimization problem utilizing the Chebyshev interval method. Initially, Chebyshev polynomials are utilized to quantify interval uncertainty, followed by an analysis of the intervals of coupling variables in multidisciplinary systems using an iterative approach. Subsequently, an interval reliability index is introduced, based on the constraint interval, with a detailed description of the calculation process provided. Furthermore, interval order relations are employed to streamline the uncertainty optimization problems, allowing for the adjustment of the optimization objective according to the interval characteristics. Two numerical examples are presented to demonstrate the accuracy and practicality of the proposed method, which effectively enhances the reliability within a precisely defined constraint interval in multidisciplinary optimization under interval uncertainties.