Screen and Optimize Material Key Factors through Fuel Rod Performance Analysis

Wang Shihuai¹, Xie Yiran², Xue Jiaxiang^2*, Li Lei², Liu Tong¹

¹ China Nuclear Power Research Institute, Chengdu, 610000, China;

² China Nuclear Power Research Institute, Shenzhen, 518000, China;

ABSTRACT: Traditional fuel performance analysis work is usually applied in the fuel design verification stage in the engineering field, aimed at optimizing the design of structural parameters for known design schemes. At this stage, the materials of each component have been finalized, the material properties have been completed, and a complete and deterministic material behavior model input is provided for fuel performance analysis. For new nuclear fuel elements, due to the long R&D cycle of the materials, the materials are still developing. As a result, a complete and determinate material performance model cannot be given, but some models related to material technologies and composition can be provided. Based on the idea of reverse design, we built a fuel performance analysis tool that includes input conditions such as material influence factors by implanting models related to material influence factors which consist of material technologies and composition into existing fuel analysis models. By use of DAKOTA, the fuel performance in a reactor was analyzed by a sensitivity analysis method based on random sampling, and the material factors that have greater effects on fuel performances could be screened. Furthermore, the optimized design parameters of materials could be obtained by multi-objective function optimization of a specific or several in-reactor performances of current new fuel rod design. By integrating the above processes, a method for screening and optimizing key factors of new nuclear fuel materials with the goal of fuel performance optimization was established, and a platform for search and optimization design of material key factors was developed to realize the feedback from fuel performance analysis to material design. Based on the existing fuel material model, a series of material impact factors and property impact functions were set up and implanted into existing fuel analysis software. Thereafter, the key factors were screened. To reduce fuel centerline temperature and rod internal pressure, the parameter optimization design was carried out. The results show that this method could be used to screen material key factors, and get the optimal parameter of every factor. With the deepening of the development of new nuclear fuel materials and the introduction of more real material property models related to processing technologies and composition, this method can rapidly feed back to the material development, so as to obtain an ideal design of new fuel material faster.

Figure 1.  The process of material key factor screening and optimizing.

Keywords: Material gene; fuel performance analysis; optimal design;