The presented paper considers the behavior of PSB-WWER facility and WWER 1000 NPP during 11% leakage transient in the upper plenum of the reactor vessel. RELAP 5/3.2 is applied for the analyzes. PSB-WWER facility is a 1/300 volume scale model of a WWER-1000, reactor installed at Electrogorsk Researc & Engineering Centre in 1998. Both nodalization are qualified, the WWER 1000 nodalization is a generic, no special NPP reference is used. In order to evaluate the nodalization performance, the comparing procedure set up at the DIMNP of Pisa University (UNIPI) has been applied that foresees two comparison levels: a ‘steady state’ level and an ‘on transient’ level. The transient is 11% equivalent break in Upper Plenum with the actuation of one high pressure injection system, connected to the hot leg of the loop #4, and 4 passive systems (ECCS hydro-accumulators), connected to the outlet plenum and to the inlet chamber of the downcomer. The low-pressure injection system is not available. The target is to compare calculation results for the test facility and the NPP and to reconsider the scaling and its influence on the transient results.
Relap5 Thermal Hydraulic Analysis 11% upper plenum leakage for PSB VVER test facility and VVER NPP
D'AURIA, FRANCESCO SAVERIO
2004-01-01
Abstract
The presented paper considers the behavior of PSB-WWER facility and WWER 1000 NPP during 11% leakage transient in the upper plenum of the reactor vessel. RELAP 5/3.2 is applied for the analyzes. PSB-WWER facility is a 1/300 volume scale model of a WWER-1000, reactor installed at Electrogorsk Researc & Engineering Centre in 1998. Both nodalization are qualified, the WWER 1000 nodalization is a generic, no special NPP reference is used. In order to evaluate the nodalization performance, the comparing procedure set up at the DIMNP of Pisa University (UNIPI) has been applied that foresees two comparison levels: a ‘steady state’ level and an ‘on transient’ level. The transient is 11% equivalent break in Upper Plenum with the actuation of one high pressure injection system, connected to the hot leg of the loop #4, and 4 passive systems (ECCS hydro-accumulators), connected to the outlet plenum and to the inlet chamber of the downcomer. The low-pressure injection system is not available. The target is to compare calculation results for the test facility and the NPP and to reconsider the scaling and its influence on the transient results.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
