Qualitative and quantitative evaluation of code uncertainties is a necessary step in the code assessment process, above all if best-estimate codes are utilized for licensing purposes. Qualitative analysis is a prerequisite for the subsequent quantitative analysis. For qualitative accuracy evaluation we used the methodology developed at the University of Pisa.
Visual observation is also part of qualitative assessment.
Due to insufficient number of calculated parameters, detailed analysis was partly limited. For the selected parameters agreement between measured and calculated pressures, fluid temperatures, break flow and accumulator behavior was good. Major discrepancies were observed in the differential pressure across the core and dryout occurrence. In almost half of the calculations core dryout was not predicted. Qualitative analysis of considered calculations also showed that FFT method can be used for quantitative analysis.