Estimation of Neutronic Performance in a Hybrid Reactor with Regression Analysis

摘要

This study presents regression analysis method used for prediction and investigation of neutronic performance in a hybrid reactor using UO_2 fuel and Flibe (Li_2BeF_4) coolant. The ~(235)U fraction is increased gradually from 0 to 4% stepped by 1 % and the ~6Li fraction within the Flibe coolant is enriched gradually to 30, 60 and 90% from 7.5%. Relations between ~(235)U fuel fraction and lithium (~6Li) enrichment are investigated for the estimation of neutronic performance as the tritium breeding ratio (TBR), energy multiplication factor (M), total fission rate (Σ_f), ~(238)U (n,γ) reaction and fissile fuel breeding (FFB) in the hybrid reactor. Regression analysis by results obtained by using the code (XSDRNPM/SCALE5) for TBR, M, Σ_f, ~(238)U (n,γ) and FFB are performed. The results of the regression analysis and the values obtained by using the code (XSDRNPM/SCALE5) are compared with respect to the TBR, M, Σ_f, ~(238)U (n,γ) and FFB of the reactor. The values calculated from the obtained formulations with regression analysis are found to be in good agreement with results obtained by using the code (XSDRNPM/SCALE5). It is observed that the derived equations from regression analysis could provide an accurate computation of the neutronic performances so that these equations could use for the prediction of TBR, M, Σ_f, ~(238)U (n,γ) and FFB. In addition, correlation matrix is calculated to determine the degree of relationship between variables as TBR, M, Σ_f, ~(238)U (n,γ) and FFB.