Nuclear-data uncertainty analysis for the start-up physics test of CPR1000 reactor

Abstract

In this paper, the uncertainty propagation has been performed from the nuclear data to the key parameters of start-up physics test for the first cycle of CPR1000 reactor. The start-up physics test is very important for the safety of PWRs, during which the key parameters including the critical boron concentration, temperature coefficient, integral worth of RCCA (Rod Cluster Control Assembly) and power distributions should be measured and used to validate the nuclear-designed ones. In order to guarantee the reactor safety, the errors between the simulation values and measurement values are required to satisfy corresponding engineering limits. However, for the conventional validation method, the uncertainties of the simulation values were ignored. Therefore, the uncertainty analysis has been performed to propagate the nuclear-data uncertainties to these key parameters of the start-up physics test for the CPR1000 reactor. Through the analysis, the absolute and relative uncertainties of these key parameters have been quantified, with the nuclear-data covariance data from ENDF/B-VII.1, ENDF/B-VIII.0 and TENDL-2017.