Thermal hydraulic response of the Advanced Neutron Source Reactor to piping breaks near the core region

摘要

This paper describes the application of the RELAP5 thermal hydraulic code to a highly subcooled, plate type reactor typical of many research and production reactor systems. The specific system modeled is the latest design of the Advanced Neutron Source Reactor (ANSR). A discussion of the model as well as the results from several loss-of-coolant accident (LOCA) scenarios is included. The results indicate that this system responds to these accidents by a very rapid depressurization (over a few milliseconds) followed by a pressure recovery due to fluid inertia. In addition, the effect of including a gas pressurized accumulator in the system is addressed. The results show that tracking the pressure response of the system over these short time scales will be a key to accurately predicting the thermal response of the core of the reactor. Further, the break time scale as well as the time scale of the thermal response of the core, presently treated conservatively, will be additional important areas of study. 22 refs.