Analysis on the Buckling Behavior of the Spacer Grid Structure for the PWR FuelAssembly

摘要

The objective of this research is to propose the methodology that could predict the buckling behavior on the spacergrid structure for the PWR(P_ressurized Water Reactor) fuel assembly. To perform this objective, the two kinds of approachare used in this work. First, in order to obtain the test data on the dynamic buckling behavior of the spacer grid, the impacttest is performed with the 5x5 cell size partial grid specimen, which is made of Zircaloy-4 thin plate. Second, a finite elementanalysis method for predicting the buckling behavior on the spacer grid structure is established by a commercial finiteelement code ABAQUS/Explicit. In this FE analysis method, appropriate boundary conditions and impact loading conditionsare applied to simulate the actual test conditions. From the impact test, the dynamic buckling phenomenon depends on theweakest layer cell, which is so called local buckling of the metal structure. In addition, the finite element analysis model is ingood agreement with the impact test results, therefore this finite element model and the analysis procedure will be used aa agood tool for predicting the dynamic buckling behavior of the grid structure.