Physical probability table applied to response matrix-collision probability method for direct whole-core transport calculations

Abstract

In this study, we applied physical probability table to response matrix-collision probability method to treat and evaluate self-shielded resonance cross-sections for whole-core transport calculations. To attain accurate results, especially in resonance treatment, the conservation laws of probabilities are derived and satisfied using HELIOS normalization scheme. The subgroup weights are efficiently evaluated using the conjugate gradient method based on the normal equations (CGNR). The resonance interference effects are considered. We used Segev method to interpolate the resonance integrals (RIs), in order to accurately obtain the subgroup weights. Finally, a validation is presented where the effective absorption and production cross-sections and the infinite multiplication factors are compared with exact values obtained using NJOY and the equivalence theory for homogeneous media. Other results, such as the Rowland’s benchmark for three assembly production cases, are also presented and compared with those produced by Monte Carlo method. The results indicate the developed method can accurately represent the self-shielding effects.