EP0051441A1
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Nuclear reactor and fuel assembly therefor
Assignee: Hitachi Ltd
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Filing: 1981-10-28
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Granted: —
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Expires: 2001-10-28
Abstract
Abstract In a fuel assembly for a nuclear reactor, which assembly has a large number of fuel rods (8) arranged in a square lattice, the fuel rods (8) being so arranged that the ratio of cross-sectional areas of coolant passage (3) and fuel pellets (1) is at least 1.9:1, in any unit square (A) of the body of the lattice. The increased ratio of the coolant to fuel promotes thermalization of neutrons, resulting in effective utilization of uranium resource. The increased ratio may be achieved by using hollow pellets, by using pellets of a smaller diameter than normal, by having an increased inter-rod spacing, or any combination of these.
Inventors
- 👤 Motoo Aoyama
- 👤 Kunitoshi Kurihara
- 👤 Renzo Takeda
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-03 11:47
CPC Classifications
G; G21; G21C; G21C3/00; G21C3/30; G21C3/32; G21C3/326; G21C3/328; Y; Y02; Y02E; Y02E30/00; Y02E30/30
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
81 words
A fuel assembly for a nuclear reactor core, the assembly having fuel rods (8) containing fuel pellets (1) and arranged in a square array within a coolant passage (3), characterized in that: on a section perpendicular to the axial direction of the assembly, the cross-sectional areas of the coolant passage (3) and of the fuel pellets (1) in any unit square of the array having corners at the centres of adjacent fuel rods are in a ratio of at least 1.9:1.
Claim 2
Dependent Claim
81 words
A fuel assembly for a nuclear reactor core, the assembly having fuel rods (8) containing fuel pellets (1) and arranged in a square array within a coolant passage (3), characterized in that: on a section perpendicular to the axial direction of the assembly, the cross-sectional areas of the coolant passage (3) and of the fuel pellets (1) in any unit square of the array having corners at the centres of adjacent fuel rods are in a ratio of at least 1.9:1.
Claim 3
Dependent Claim
24 words
A fuel assembly according to claim 1 suitable for a core of a boiling water type reactor which uses light water as a coolant.
Claim 4
Dependent Claim
19 words
A fuel assembly according to claim 1 or claim 2 having hollow pellets (1) in the fuel rods (8).
Claim 5
Dependent Claim
26 words
A fuel assembly according to claim 1, claim 2 or claim 3 in which the fuel pellets (1) have a diameter of less than 10.31 mm.
Claim 6
Dependent Claim
16 words
A nuclear reactor having a core charged with a fuel assembly according to any preceding claim.
References Cited (Backward Citations)
US3105026A
Cited
DE1141033B
Cited
FR1285565A
Cited
US3227621A
Cited
US3158549A
Cited
US3749640A
Cited
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