Application of Sampling Based Sensitivity Analysis in Evaluation of LBLOCA Mass and Energy Release PIRT

The sampling based statistical sensitivity analysis is an effective sensitivity analysis method, and the importance of input parameters of a thermal hydraulic analysis code could be evaluated by calculating the correlation coefficients of input parameters and output parameters. A sampling based sensitivity analysis method for LBLOCA mass and energy release of the large passive plant was developed, by coupling DAKOTA and WCOBRA/TRAC codes. The calculated results show that the initial core power, fuel burnup, decay heat, initial accumulator water temperature, initial accumulator water volume, accumulator pipe friction coefficient, initial core makeup tank water temperature, discharge coefficient and break resistance coefficient affect mass and energy release greatly. The results can provide quantitative support for evaluation of LBLOCA mass and energy release analysis phenomena identification and ranking table.