ASTEC and ICARE / CATHARE are computer codes allowing analysing severe accidents in LWRs. The applicability of these codes to Russian reactors of VVER type is a clear common IRSN-GRS objective. The current work in col...ASTEC and ICARE / CATHARE are computer codes allowing analysing severe accidents in LWRs. The applicability of these codes to Russian reactors of VVER type is a clear common IRSN-GRS objective. The current work in collaboration between IRSN and RRC K1 （Russia） aims at reaching this objective. This paper is devoted to ASTEC and ICARE / CATHARE simulations of a severe accident scenario on a VVER-1000. A Large Break LOCA （850 mm） sequence accompanied with the station blackout was selected for analysis. ICARE / CATHARE V2.2 successfully predicted main events of the accident： heat-up of the core, core degradation and melt relocation to the lower part of the core. A simulation of a complete accidental sequence was performed with ASTEC V 1.3-rev3 code： core heat-up and melting, melt relocation, reactor vessel rupture, molten corium / concrete interaction, release and distribution of steam, H2, CO, CO2, fission products and aerosols in the RCS and the containment. It must be pointed out that, as concerns the thermalhydraulics front-end phase and the in-vessel degradation phase, the ASTEC simulation exhibited consistent results with respect to the best-estimate ICARE / CATHARE ones.展开更多
文摘ASTEC and ICARE / CATHARE are computer codes allowing analysing severe accidents in LWRs. The applicability of these codes to Russian reactors of VVER type is a clear common IRSN-GRS objective. The current work in collaboration between IRSN and RRC K1 （Russia） aims at reaching this objective. This paper is devoted to ASTEC and ICARE / CATHARE simulations of a severe accident scenario on a VVER-1000. A Large Break LOCA （850 mm） sequence accompanied with the station blackout was selected for analysis. ICARE / CATHARE V2.2 successfully predicted main events of the accident： heat-up of the core, core degradation and melt relocation to the lower part of the core. A simulation of a complete accidental sequence was performed with ASTEC V 1.3-rev3 code： core heat-up and melting, melt relocation, reactor vessel rupture, molten corium / concrete interaction, release and distribution of steam, H2, CO, CO2, fission products and aerosols in the RCS and the containment. It must be pointed out that, as concerns the thermalhydraulics front-end phase and the in-vessel degradation phase, the ASTEC simulation exhibited consistent results with respect to the best-estimate ICARE / CATHARE ones.
