Study on post-BT heat transfer in a full scale bwr ( [formula omitted]) rod bundle

Abstract

Post-BT heat transfer experiments on a full scale BWR ( 8 × 8) rod bundle were conducted at the Nuclear Power Engineering Test Center (NUPEC), which is sponsored by the Ministry of International Trade and Industry (MITI). Demineralized water was used as a test fluid. The experimental conditions were: Mass flux: 284 to 1562 kg/m 2s, Pressure: 7.15 MPa, Inlet subcooling: 50 kJ/kg. Test results indicate that the rod temperature rise after boiling transition (BT) is not “excursive”. Comparisons with several existing post-BT correlations indicate that the Groeneveld, The Dougall-Rohsenow and the Condie-Bengston correlations tend to be conservative in the intermediate range before the onset of fully developed film boiling, while the Koizumi and the Sugawara correlations predict well over the complete Post-BT range.