Convex shaped FBR core with graded size pins to prevent re-criticality during Core Disruptive Accident

Autor: Naoyuki Takaki, Keiko Chitose
Rok vydání: 2019
Předmět:
Zdroj: Annals of Nuclear Energy. 127:364-371
ISSN: 0306-4549
DOI: 10.1016/j.anucene.2018.12.022
Popis: The core geometry of sodium-cooled fast spectrum reactor (SFR) is not generally in its most reactive configuration. Therefore, the study of postulated Core Disruptive Accident (CDA) has been recognized as one of the most important themes for SFR. There are several analyses and experiments to investigate CDA phenomena. On the basis of these knowledge, some special devices are designed to control the relocation of molten material. This study focuses on the core configuration to maximize neutron leakage effect during its geometrical deforming, instead of introduction of the devices. The authors investigate the convex shaped core design that is closed to spherical shape. It is because the oval spherical core has the least neutron leakage in all practical core geometries. The neutron leakage of the convex shaped core increases by geometry change and it causes negative compaction reactivity insertion. In this paper, the feasibility of the convex shaped core design is investigated based on the parametric survey of compaction reactivity using the neutron diffusion calculation. The convex shaped core with uniform size pins and less neutron leakage shows negative compaction reactivity but the radial power distribution is not flattened. The introduction of graded size pins enables convex core to accomplish negative compaction reactivity and leveled power, simultaneously.
Databáze: OpenAIRE
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