Self-actuated shutdown system for a commercial size LMFBR. Final report
A Self-Actuated Shutdown System (SASS) is defined as a reactor shutdown system in which sensors, release mechanisms and neutron absorbers are contained entirely within the reactor core structure, where they respond inherently to abnormal local process conditions, by shutting down the reactor, independently of the plant protection system (PPS). It is argued that a SASS, having a response time similar to that of the PPS, would so reduce the already very low probability of a failure-to-scram event that costly design features, derived from core disruptive accident analysis, could be eliminated. However, the thrust of the report is the feasibility and reliability of the in-core SASS hardware to achieve sufficiently rapid shutdown. A number of transient overpower and transient undercooling-responsive systems were investigated leading to the selection of a primary candidate and a backup concept. During a transient undercooling event, the recommended device is triggered by the associated rate of change of pressure, whereas the alternate concept responds to the reduction in core pressure drop and requires calibration and adjustment by the operators to accommodate changes in reactor power.
- Research Organization:
- Combustion Engineering, Inc., Windsor, CT (United States)
- OSTI ID:
- 6354571
- Report Number(s):
- EPRI-NP-846; TRN: 79-007710
- Country of Publication:
- United States
- Language:
- English
Similar Records
Design criteria for a self-actuated shutdown system to ensure limitation of core damage. [LMFBR]
Self-actuating reactor-shutdown system. [LMFBR]
Related Subjects
21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS
LMFBR TYPE REACTORS
REACTOR SAFETY FUSES
DESIGN
CONTROL ELEMENTS
REACTOR PROTECTION SYSTEMS
REACTOR SHUTDOWN
SCRAM
BREEDER REACTORS
EPITHERMAL REACTORS
FAST REACTORS
FBR TYPE REACTORS
LIQUID METAL COOLED REACTORS
REACTOR COMPONENTS
REACTORS
SHUTDOWNS
220400* - Nuclear Reactor Technology- Control Systems
210500 - Power Reactors
Breeding