The fuel-coolant interaction may lead to an energetic steam explosion. The strength of the steam explosion is limited by melt solidification, which prevents the fine fragmentation of the melt. An improved model of the solidification influence on the fuel-coolant interaction was developed. The solidification influence modelling is strongly related to the modelling of the temperature profile and the mechanical effect of the crust on the fragmentation process. The simulation results confirmed the appropriateness of the proposed approach.
COBISS.SI-ID: 24021799
An assessment of ex-vessel steam explosion pressure loads in a typical pressurized water reactor cavity was performed with the FCI code MC3D. To be able to perform a series of simulations, the reactor cavity was modelled in a simplified 2D geometry, trying to assure that the 2D simulation results reflect qualitatively and quantitatively as closely as possible the conditions in a real reactor cavity. A spectrum of relevant scenarios has been analysed and a sensitivity study has been performed addressing the influence of the jet breakup modelling and the melt droplets solidification on the FCI process. The sensitivity study revealed that the jet breakup and the melt droplets solidification have a significant influence on the strength of the steam explosion.
COBISS.SI-ID: 25015847