Statistical Approach to Sensitivity Analysis of the Computer Simulation Codes

Abstract

A procedure to estimate the sensitivity of a dependent variable of the computer simulation codes with respect to a set of independent variables in the code is developed. The methodology is applied to the computer code COBRA-II which simulate the thermal Hydraulics of the nuclear reactors at subchannel level. The method uses Stratified Fractional Factorial Sampling for data preparation. The mathematical method of orthogonal central composite design is used to develop a response surface in form of a complete polynomial. The sensitivity is determined by differentiating the model with respect to each parameter while all the other parameters are kept at their nominal values.