Based on the ASTRUM method, an uncertainty analysis of hydrogen production and severe accident process under severe accident conditions of small pressurized water reactors was conducted with respect to the input parameters. By coupling the uncertainty analysis program DAKOTA with the severe accident system analysis program MELCOR,We simulated the process of a severe accident triggered by a Station Blackout Accident. Based on the PIRT table, the uncertainty input parameters and their distribution ranges were determined. Research shows that the established analytical method can effectively simplify the modeling and data processing procedures, enhance computational efficiency and ensure good accuracy; at different stages of the accident, the key influencing factors of hydrogen production vary; Under the assumed conditions, the hydrogen production rate and start melting time of the core are relatively sensitive to the oxidation rate of the zirconium alloy.
Xu et al. (Sun,) studied this question.