Preliminary accident analysis to support a passive depressurization systems design

Journal Article · Wed May 01 04:00:00 EDT 1996 · Nuclear Technology

OSTI ID:248108

Lenti, R; Mansani, L; Saiu, G ^[1]

---

1. Ansaldo, Genoa (Italy). Nuclear Div.

The new generation of evolutionary nuclear power plants, e.g., the Westinghouse AP600 and the General Electric simplified boiling water reactor, relies on a full reactor coolant system (RCS) depressurization to allow gravity injection from an in-containment tank and thereby assure long-term core cooling. Studies performed to support the licensing process and design of both evolutionary and innovative reactors have shown that cold water injection may, under particular plant conditions, induce a large plant depressurization. Preliminary studies have been performed to support the design of a passive injection and depressurization system (PIDS) based on the idea of depressurizing the RCS by mixing cold water with the RCS hot water and inducing steam condensation in the primary system. The analyses, performed with the RELAP5/MOD3 computer code, show the response of a typical midsize pressurized water reactor plant [two loops, 600 MW (electric)] equipped with the PIDS. Different RCS injection locations including pressurizer, vessel upper head, and hot leg, and actuation at different residual reactor coolant masses have been investigated. The PIDS performance has also been verified against the following reference severe accident scenarios: (a) complete station blackout event, and (b) a small-break loss-of-coolant accident and concomitant station blackout event.

• OSTI ID: 248108
• Journal Information: Nuclear Technology, Journal Name: Nuclear Technology Journal Issue: 2 Vol. 114; ISSN 0029-5450; ISSN NUTYBB
• Country of Publication: United States
• Language: English

Related Subjects

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS
22 GENERAL STUDIES OF NUCLEAR REACTORS
BWR TYPE REACTORS
DEPRESSURIZATION
DESIGN
ENGINEERED SAFETY SYSTEMS
GRAVITATION
PERFORMANCE
PWR TYPE REACTORS
REACTOR ACCIDENTS
REACTOR COOLING SYSTEMS