In-vessel melt pool coolibility test—Description and results of LIVE experiments

The LIVE test program investigates in-vessel melt pool behaviour and cooling strategies for in-vessel corium retention during severe accidents in LWRs. The main part of the LIVE facility is a 1:5 scaled semi-spherical lower head of a typical pressurized water reactor. Up to now, LIVE experiments have been performed in different external cooling conditions, melt volumes and heat generation rates. At present the well-known simulant material KNO3–NaNO3 in non-eutectic composition (80 mole% KNO3–20 mole% NaNO3) and in eutectic composition (50 mole% KNO3–50 mole% NaNO3) is used. This work presents the behaviour of a homogenous melt pool regarding the 3D heat flux distribution through vessel wall, melt pool temperature, crust thickness and the pool melt composition in transient and in steady state conditions.

Research highlights▶ This work investigated in-vessel melt pool behaviour of PWR in LIVE facility. Different relocation scenarios and external cooling conditions were investigated. Valuable experimental data have been obtained about homogenous melt pool behaviour. These data include melt temperature, heat flux and crust characteristics.