Sensitivity And Uncertainty Analysis Of PWR Using SUACL

Sensitivity and uncertainty analysis are important for assessing reactor safety and improving reactor economics.Through the uncertainty analysis of the PWR fuel assembly and the core,the propagation of the uncertainty of the nuclear data is calculated.T he TMI-1 reactor was analyzed with reference to the OECD/NEA Model Uncertainty Analysis Benchmark(UAM).This analysis mainly uses the self-developed sampling method based uncertainty and sensitivity analysis code SUACL(Sensitivity and Uncertainty Analysis Code for Lighter water reactor)and component calculation program DRAGON3.06.Nuclear data is the basis for reactor design and one of the main sources of uncertainty in reactor design.In this study,the effective multiplication factors caused by nuclear data and the uncertainty of neutron flux calculation in the core are studied.Based on the ENDF/B-Ⅶ.1 nuclear evaluation database,a covariance matrix is processed,and then the samples of different reaction channels are generated by the program SUACL.The component calculation program DRAGON3.06 is used to calculate the infinite medium growth factor which generates two group parameters and systems.The uncertainty of the analysis of the two-group parameters is consistent with the related references.At the same time,the sensitivity coefficient calculation method based on statistical sampling method is studied.The calculation results are compared with the direct perturbation method,and the results are in good agreement.This verifies the correctness of the sensitivity coefficient and uncertainty analysis methods based on statistical sampling method.In addition,the core calculation program TRIVAC was used to analyze the uncertainty of the neutron flux density calculated by an example core model.This result lays a good foundation for further analysis in the future.