Nuclear Technology / Volume 148 / Number 1 / October 2004 / Pages 12-24
Technical Paper / RETRAN
Two advanced boiling water reactors (ABWRs) whose electric output power is 1356 MW have been commercially operated since 1996 and 1997 by the Tokyo Electric Power Company (TEPCO) in Japan. Features of an ABWR are reactor internal pumps (RIPs) placed in the lower plenum and downcomer, peripherally bottom-mounted on the reactor pressure vessel - which should require different modeling from the jet pumps and two recirculation pumps in the primary outer-loop recirculations of BWR-5.
Efforts focused on modeling and simulating the ABWR with transient analyses by the point-kinetics model with the local reactivity modified by local importance weighting of the squared nodal power during start-up tests using the RETRAN-3D code, version MOD003 without three-dimensional kinetics. The core and reactor pressure vessel including ten ABWR RIPs and the steam lines were modeled, and simulations were carried out for the cases of the one-pump trip test, the changing-setpoint tests, the main-steam-isolation-valve-closure test, and the generator load rejection test with bypass.
The analytical simulation with RETRAN-3D/MOD003 well reproduced the measured data of the ABWR in operation for the RIP trip and the transient tests and could demonstrate its validation for applying to the ABWR with modeling of RIPs.