Abstract
A new uncertainty reduction method is proposed to evaluate the prediction accuracy of neutronics characteristics by combining the generalized bias factor method and the cross section adjustment method. The present method is applied to a fuel fabrication process with erbia-bearing fuel. The cross section uncertainty of erbium is improved by means of cross section adjustment using experimental data of the erbia worths. For a blending machine (H/U = 0) used in the fuel fabrication process, the uncertainty reduction, which shows the rate of reduction of uncertainty, of the keff is 0.604 for the present method and 0.555 for the conventional bias factor method. Thus, the prediction uncertainties are reduced by the present method compared with by the bias factor method.