Uncertain Multidisciplinary Design Optimization on Next Generation Subsea Production System by Using Surrogate Model and Interval Method.

The innovative Next Generation Subsea Production System (NextGen SPS) concept is a newly proposed petroleum development solution in ultra-deep water areas. The definition of NextGen SPS involves several disciplines, which makes the design process difficult. In this paper, the definition of NextGen SPS is modeled as an uncertain multidisciplinary design optimization (MDO) problem. The deterministic optimization model is formulated, and three concerning disciplines—cost calculation, hydrodynamic analysis and global performance analysis are presented. Surrogate model technique is applied in the latter two disciplines. Collaborative optimization (CO) architecture is utilized to organize the concerning disciplines. A deterministic CO framework with two discipline-level optimizations is proposed firstly. Then the uncertainties of design parameters and surrogate models are incorporated by using interval method, and uncertain CO frameworks with triple loop and double loop optimization structure are established respectively. The optimization results illustrate that, although the deterministic MDO result achieves higher reduction in objective function than the uncertain MDO result, the latter is more reliable than the former. [ABSTRACT FROM AUTHOR]