The Generic Containment SB-LOCA accident simulation: Comparison of the parameter uncertainties and user-effect

This paper present analysis, which is an extension of the “Generic Containment” benchmark and investigates the effect of input parameter's uncertainties in comparison to the user effect. Calculations were performed using the computer code ASTEC, the uncertainty and sensitivity of the results were estimated using GRS method and tool SUSA. The results of the present analysis show, that while there are differences between the uncertainty bands of the parameters, in general the deviation bands caused by parameters' uncertainty and the user effect are comparable and of the same order. The properties of concrete and the surface areas may have more influence on containment pressure than the user effect and choice of computer code as identified in the SARNET2 Generic Containment activity. It was identified and discussed that the definition of conservative parameters is complicated due to the fact that conservatism in terms of pressure level conflicts with conservatism regarding the gas mixture flammability.