Application of ASTEC, MELCOR, and MAAP Computer Codes for Thermal Hydraulic Analysis of a PWR Containment Equipped with the PCFV and PAR Systems

Table 1

Time sequence of main events during the in-vessel phase.

Event	ASTEC	MELCOR	MAAP
Two-phase flow at the break	3800 s	2900 s	4000 s
Loss of the SG heat sink	4310 s	3540 s	4500 s
Core uncovery	5150 s	4050 s	4990 s
Onset of fuel rod cladding oxidation	5350 s	4350 s	5250 s
Start of the core melting	5960 s	4750 s	6330 s
Melt relocation to the lower head	6380 s	6100 s	9630 s
RPV failure	9440 s	9080 s	15020 s