Natural convection for in-vessel retention at prototypic

The ACOPO experiment simulates natural convection heat transfer from volumetrically heated pools at a half-scale reactor lower head geometry (hemispherical). New data for internal Rayleigh numbers of up to 10^16 are presented, correlated and discussed. in relation lo other available correlations. These ACOPO results confirm a key component of the in-vessel retention severe accident management strategy for an AP600-like design, as recently established in DOE/ID-10460.