ABSTRACT
Direct containment heating is a phenomenon identified to occur in a light water reactor during a meltdown accident at high system pressures at the time of vessel breach. Immediate containment failure may result from this process due to overpressure and overtemperature loads. This paper focuses on the “science” of direct heating and the reactor safety criteria and issues that must be addressed to assure the threat to containment is minimized. This discussion attempts to be tutorial in nature with the broader context of melt-cool ant-atmosphere i nteracti ons being emphasized. From this discussion future research needs may be suggested.
