Small-break LOCA analysis for a typical Westinghouse three-loop PWR with large, dry containment

[[abstract]]Reports on a series of small-break LOCA analyses for a typical Westinghouse 3-loop PWR, with a large, dry containment, using the MAAP 3.0 code. Calculations include a presumed base case study, sensitivity studies, and operator actions for S2DJ and S2WH accidents. The analyses cover both primary-system and containment responses. The calculated results show that in certain cases, containment spray (after reactor vessel failure) would result in the early occurrence of global burns. An early containment spray (before vessel failure) would cause an earlier vessel failure time in the S2WH accident. In some S2DJ cases, a small LOCA break area may mean an earlier vessel failure time compared with that in the cases with large LOCA breaks. In the cases studied in this work, the proper functioning of either the containment spray or fan cooler could prevent the containment from failure. However, the containment would fail if neither containment spray nor fan cooler is available. Operator actions could provide little help in the S2DJ accident. While in S2WH accident, proper operator actions could significantly lengthen the time for the core to be covered or even could prevent the core from being damaged.[[fileno]]2060131010060[[department]]工程與系統科學