Influence Of Low Boron Core Design On PWR Transient Behavior

Conference · Sat Jul 01 04:00:00 EDT 2006

OSTI ID:20997100

Aleksandrov Papukchiev, Angel; Liu, Yubo ^[1]; Schaefer, Anselm ^[2]

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1. Technical University Munich, Arcisstrasse 21, 80333 Muenchen (Germany)
2. ISaR Institute for Safety and Reliability, Walther-Meissner-Str. 2 85748 Garching (Germany)

In conventional pressurized water reactor (PWR) designs, the concentration of boron in primary coolant is limited by the requirement of having a negative moderator density coefficient. As high boron concentrations have significant impact on reactivity feedback properties, design changes to reduce boron concentration in the reactor coolant are of general interest in view of improving PWR inherent safety. In the framework of an investigation into the feasibility of low boron design, a PWR core configuration based on fuel with higher gadolinium (Gd) content has been developed which permits to reduce the natural boron concentration at begin of cycle (BOC) by approx. 50% compared to current German PWR technology. For the assessment of the potential safety advantages, a Loss-of-Feedwater Anticipated Transient Without Scram (ATWS LOFW) has been simulated with the system code ATHLET for two PWR core designs: a low boron design and a standard core design. The most significant difference in the transient performance of both designs is the total primary fluid mass released through the pressurizer (PRZ) valves. It is reduced by a factor of four for the low boron reactor, indicating its improved density reactivity feedback. (authors)

• Research Organization: The ASME Foundation, Inc., Three Park Avenue, New York, NY 10016-5990 (United States)
• OSTI ID: 20997100
• Country of Publication: United States
• Language: English

Related Subjects

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS
ATWS
BORON
COOLANTS
DENSITY
DESIGN
FEEDWATER
GADOLINIUM
MODERATORS
PERFORMANCE
PRIMARY COOLANT CIRCUITS
PWR TYPE REACTORS
REACTIVITY COEFFICIENTS
REACTOR SAFETY
SCRAM
STANDARDS
TRANSIENTS
VALVES