Natural convection for in-vessel retention at prototypic Rayleigh numbers

The ACOPO experiment simulates natural convection heat transfer from volume trically heated pools at a half-scale reactor lower head geometry (hemisphe rical). New data for internal Rayleigh numbers of up to 10(16) are presente d, correlated and discussed, in relation to other available correlations. T hese ACOPO results confirm a key component of the in-vessel retention sever e accident management strategy for an AP600-like design, as recently establ ished in DOE/ID-10460. (C) 2000 Elsevier Science S.A. All rights reserved.