Design of a Spacer Grid Using Axiomatic Design

Abstract

Recently, much attention is focused on the design of fuel assemblies in the Pressurized Light Water Reactor (PWR). The spacer grid is one of the main structural components in a fuel assembly. It supports fuel rods, guides cooling water, and maintains geometry from external impact loads. In this research, a new shape of the spacer grid is designed by axiomatic approach. The Independence Axiom is utilized for the design. For the conceptual design, functional requirements (FRs) are defined and corresponding design parameters (DPs) are found to satisfy corresponding FRs in sequence. Overall configuration and shapes are determined in this process. Detailed design is carried out based on the sequence from axiomatic design. For the detailed design, the system performances are evaluated by using linear and nonlinear finite element analyses. The dimensions are determined by optimization. Some commercial codes are utilized for the analysis and design.