Feasibility Study of Heterogeneous Resonance Integral Table of ²³⁸U

As the complexity and accuracy requirement increase of neutronics calculation of the next generation reactor, it is necessary to introduce the heterogeneous resonance integral table into the multi-group cross section library replacing the homogeneous resonance integral table. The accuracy of embedded self-shielding calculation using heterogeneous resonance integral tables of ²³⁸U prepared in different schemes was analyzed. The results show that the density of the moderator and the concentration of boron are crucial in the practical application of heterogeneous resonance integrals. Based on the analysis results, the current scheme of the 2D heterogeneous resonance integral table was improved by a 4D interpolation table to cover all possible operating conditions of PWR. Numerical results show that the improved heterogeneous resonance integral table enhances the accuracy of resonance calculation and improves the applicability of the multi-group library.