Estimating uncertainty in thermal-hydraulic codes using the linear variate method

Thermal-hydraulic computer codes represent non-linear functions that may contain discontinuities. This paper reports that Monte Carlo methods are an effective means of accurately evaluating the effect of uncertainty on a nonlinear function with discontinuities, but the computational requirements of standard Monte Carlo methods may be prohibitive. The linear variate Monte Carlo method is a means of reducing the computational requirements. The linear variate method combines the linear response surface method with Monte Carlo analysis to obtain an efficient and accurate method of nonlinear uncertainty analysis. The method is applied to the power limit analysis for the Savannah River Site reactors