INVESTIGATION OF OPTIMIZATION PROCESS FOR CORE DESIGN WITH INTEGRATED ANALYSIS BETWEEN NEUTRONICS AND PLANT DYNAMICS

Abstract

To achieve an innovative core design, an optimization process for a core design has been developed as a part of the design optimization support tool named ARKADIA-Design. The core design optimization process integrated the core design analysis of neutronics, thermal-hydraulics, and fuel integrity and plant dynamics analysis with the Bayesian optimization (BO) algorithm is being developed. The BO can reduce the total number of iterative calculations and enhance the efficiency of the optimization. To establish a basic framework of the optimization process, a representative problem following an actual core design procedure was defined. Here, core design parameters are optimized to show a high core performance with inherent safety by preventing core damage in an unprotected loss of flow event of sodium-cooled fast reactors. In this study, to confirm an applicability of the optimization process with the BO algorithm for the representative problem, a single-objective optimization problem was solved by performing the integrated analysis only between neutronics and plant dynamics as a first trial. In addition, an effectiveness of the optimization process was discussed by comparing with an ordinary core design process. An optimal solution in the representative problem was acquired by performing the integrated analysis with the constraint BO.