JPH079473B2 - Fuel assembly - Google Patents

Fuel assembly

Info

Publication number
JPH079473B2
JPH079473B2 JP1028422A JP2842289A JPH079473B2 JP H079473 B2 JPH079473 B2 JP H079473B2 JP 1028422 A JP1028422 A JP 1028422A JP 2842289 A JP2842289 A JP 2842289A JP H079473 B2 JPH079473 B2 JP H079473B2
Authority
JP
Japan
Prior art keywords
fuel
fuel assembly
outer cylinder
reactor
flow rate
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
JP1028422A
Other languages
Japanese (ja)
Other versions
JPH02206797A (en
Inventor
満 神戸
一男 羽賀
Original Assignee
動力炉・核燃料開発事業団
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 動力炉・核燃料開発事業団 filed Critical 動力炉・核燃料開発事業団
Priority to JP1028422A priority Critical patent/JPH079473B2/en
Priority to FR9001306A priority patent/FR2642887B1/en
Publication of JPH02206797A publication Critical patent/JPH02206797A/en
Publication of JPH079473B2 publication Critical patent/JPH079473B2/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • G—PHYSICS
    • G21—NUCLEAR PHYSICS; NUCLEAR ENGINEERING
    • G21C—NUCLEAR REACTORS
    • G21C3/00—Reactor fuel elements and their assemblies; Selection of substances for use as reactor fuel elements
    • G21C3/30—Assemblies of a number of fuel elements in the form of a rigid unit
    • G21C3/32—Bundles of parallel pin-, rod-, or tube-shaped fuel elements
    • G—PHYSICS
    • G21—NUCLEAR PHYSICS; NUCLEAR ENGINEERING
    • G21C—NUCLEAR REACTORS
    • G21C1/00—Reactor types
    • G21C1/02—Fast fission reactors, i.e. reactors not using a moderator ; Metal cooled reactors; Fast breeders
    • G21C1/022—Fast fission reactors, i.e. reactors not using a moderator ; Metal cooled reactors; Fast breeders characterised by the design or properties of the core
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E30/00—Energy generation of nuclear origin
    • Y02E30/30—Nuclear fission reactors

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  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Plasma & Fusion (AREA)
  • General Engineering & Computer Science (AREA)
  • High Energy & Nuclear Physics (AREA)
  • Monitoring And Testing Of Nuclear Reactors (AREA)

Description

【発明の詳細な説明】 ＜産業上の利用分野＞ この発明は、原子炉、特に出力規模の小さい高速炉に使
用するための燃料集合体に関するものである。TECHNICAL FIELD The present invention relates to a fuel assembly for use in a nuclear reactor, in particular, a fast reactor having a small power scale.

＜従来の技術＞ 従来、高速炉には、第５図に示す構造の燃料集合体が一
般的に使用されている。この一般的な燃料集合体は燃料
ピン１が200〜300本程度まとめられて断面正六角形の筒
状のラッパ管２に収納されている。このラッパ管２の下
端にはエントランスノズル３を備え、このエントランス
ノズル３により冷却材の流量配分が行なわれている。ま
た、上端には燃料取扱いのためのハンドリングヘッド４
が備えられている。<Prior Art> Conventionally, a fuel assembly having a structure shown in FIG. 5 is generally used in a fast reactor. In this general fuel assembly, about 200 to 300 fuel pins 1 are grouped together and housed in a tubular trumpet tube 2 having a regular hexagonal cross section. An entrance nozzle 3 is provided at the lower end of the trumpet tube 2, and the flow rate of the coolant is distributed by the entrance nozzle 3. In addition, a handling head 4 for handling fuel is provided at the upper end.
Is provided.

更に高速炉に使用される燃料集合体としては第６図の構
造のものが知られている。この燃料集合体は、上記一般
的な燃料集合体からラッパ管２を外し、代りに６本の支
柱５によりエントランスノズル３とハンドリングヘッド
４を支持した構造となっている。この剥き出し型の燃料
集合体においては燃料ピン１は軸方向に何段かのグリッ
ド６で固定されている。Further, as a fuel assembly used in a fast reactor, the structure of FIG. 6 is known. This fuel assembly has a structure in which the trumpet tube 2 is removed from the above-mentioned general fuel assembly, and the six support columns 5 instead support the entrance nozzle 3 and the handling head 4. In this bare fuel assembly, the fuel pins 1 are fixed in the axial direction by several grids 6.

＜発明が解決しようとする課題＞ 上に説明した第５図に示す構造の燃料集合体は、炉心圧
損が3.5Kg/cm2と大きく、原子炉運転中に燃料集合体が
膨張し、これによりラッパ管と燃料ピンの相互干渉（BD
I）及び隣接するラッパ管同士の相互干渉（DDI）が生じ
てラッパ管が変形し、このラッパ管の変形が燃料を長寿
命化する上での制約条件の一つになっているばかりか、
放射性物質で汚染された多量のラッパ管を廃棄しなけれ
ばならないという問題を有する。<Problems to be Solved by the Invention> The fuel assembly having the structure shown in FIG. 5 described above has a large core pressure loss of 3.5 Kg / cm 2, and the fuel assembly expands during the operation of the reactor, which causes Mutual interference between trumpet tube and fuel pin (BD
I) and mutual interference (DDI) between adjacent trumpet tubes causes deformation of the trumpet tube, and this deformation of the trumpet tube is not only one of the constraint conditions for extending the life of the fuel,
There is a problem that a large amount of trumpet pipes contaminated with radioactive materials must be discarded.

他方、第６図に示す構造の燃料集合体においては炉心へ
の冷却材の流量配分が不可能であり、従って径方向の出
力分布を平坦化する上で不都合であるという問題を有す
る。On the other hand, in the fuel assembly having the structure shown in FIG. 6, it is impossible to distribute the flow rate of the coolant to the core, and therefore there is a problem in flattening the radial power distribution.

また、上記いずれの燃料集合体においてもこれ等が使用
される原子炉に回転プラグ、燃料交換機、燃料出入機等
の燃料交換システムが必要とされ、また、約１年毎に原
子炉を停止して総数の何分の１かに相当する燃料集合体
を交換することも必要とされ、更に前記燃料交換システ
ムは、原子炉を構成する上でかなりのコストを占め、特
に主力規模を下げるにつれてこのコストの占める割合が
増す傾向にあり、加えて原子炉構造の小型化の障害とな
っている。Further, in any of the above fuel assemblies, the reactors in which these are used require a fuel exchange system such as a rotary plug, a fuel exchanger, a fuel inlet / outlet machine, and the reactor is shut down about every one year. It is also necessary to replace a fraction of the total number of fuel assemblies, and the refueling system occupies a considerable cost in constructing a nuclear reactor. The cost ratio tends to increase, which is an obstacle to downsizing of the reactor structure.

従って、この発明は、上記欠点を排除し、出力規模が小
さくても発電単価等が大型原子炉のそれとほぼ匹敵し、
大型原子炉とコスト的に競合し得る小型原子炉に適した
原子炉構造の簡略化、特に燃料交換システムの省略を行
うことが出来、繁雑な燃料交換を必要としない燃料集合
体を提供することを目的とする。Therefore, the present invention eliminates the above drawbacks, and even if the output scale is small, the power generation unit price and the like are almost comparable to those of large reactors,
To provide a fuel assembly capable of simplifying a reactor structure suitable for a small reactor which can compete with a large reactor in cost, particularly omitting a fuel exchange system, and not requiring complicated fuel exchange. With the goal.

さらにこの発明は、燃料集合体の径方向の冷却材流量配
分を調節することによって、径方向の出力分布を平坦化
できる燃料集合体を提供することを目的とする。A further object of the present invention is to provide a fuel assembly capable of flattening the radial power distribution by adjusting the coolant flow distribution in the radial direction of the fuel assembly.

＜課題を解決するための手段＞ この発明の燃料集合体は、上端と下端が開口した外筒内
に多数の燃料ピンを配置するとともに、これらの燃料ピ
ンを互いに所定間隔離間して固定するグリッドを燃料ピ
ン軸方向に複数段設け、前記多数の燃料ピンを内側領域
と外側領域とに仕切る隔壁を前記外筒内に該外筒と同軸
的に配設し、前記外筒の下端開口部の前記外側領域部分
に冷却材流量調節手段を設けたことを特徴とするもので
ある。<Means for Solving the Problems> In the fuel assembly of the present invention, a grid for arranging a large number of fuel pins in an outer cylinder having an open upper end and a lower end and fixing the fuel pins at a predetermined distance from each other. Are provided in a plurality of stages in the axial direction of the fuel pin, and a partition wall for partitioning the large number of fuel pins into an inner region and an outer region is disposed in the outer cylinder coaxially with the outer cylinder, and a lower end opening of the outer cylinder is provided. It is characterized in that a coolant flow rate adjusting means is provided in the outer region portion.

前記の冷却材流量調節手段は流量調節オリフィスから構
成することが好ましい。The coolant flow rate adjusting means preferably comprises a flow rate adjusting orifice.

＜作 用＞ 上記燃料集合体においては、グリッドにより燃料ピン同
士及び燃料ピンと外筒との間隔が適当に離間して保持さ
れる。このため原子炉運転中の膨張に対しても外筒と燃
料ピン及び隔壁と燃料ピンの相互干渉がほとんど生じな
い。<Operation> In the above fuel assembly, the fuel pins are held by the grid and the fuel pins and the outer cylinder are appropriately spaced from each other. Therefore, mutual interference between the outer cylinder and the fuel pin and between the partition wall and the fuel pin hardly occurs even when the reactor is expanded during operation.

また、隔壁により外筒内の多数の燃料ピンを内側領域と
外側領域に仕切り、外筒の下端開口部の外側領域部分に
冷却材流量調節手段を設けているので、燃料集合体径方
向の出力分布を平坦化するための冷却材の流量配分を効
果的に行うことができる。Further, since a large number of fuel pins in the outer cylinder are partitioned by the partition into an inner area and an outer area, and a coolant flow rate adjusting means is provided in an outer area portion of the lower end opening of the outer cylinder, the output in the radial direction of the fuel assembly is obtained. The flow rate distribution of the coolant for flattening the distribution can be effectively performed.

燃料交換に際しては、この燃料集合体全体を一括交換す
る。When exchanging fuel, the entire fuel assembly is collectively exchanged.

＜実施例＞ 以下に実施例を示し、この発明を更に具体的に説明す
る。<Examples> The present invention will be described more specifically with reference to the following examples.

第１図は、この発明の燃料集合体の１例を概略的に示す
もので、例えば電力100MWを出力する発電用原子炉の炉
心に使用する場合には、10,000本程度の燃料ピン１が軸
方向に複数段設けられたグリッド６により互いに適当間
隔離間して固定されている。また、多数の燃料ピン１は
第２図ａに示す用に断面正六角形の隔壁７で内側領域Ｉ
及び外側領域IIに仕切られている。更に外側領域IIの燃
料ピン１は上下端が開口した外筒８で囲まれ、この外筒
８の下端開口部には外側領域IIにおいて流量調節オリフ
ィス９が設けられている。FIG. 1 schematically shows an example of the fuel assembly of the present invention. For example, when it is used in the core of a power generation reactor that outputs 100 MW of electric power, about 10,000 fuel pins 1 The grids 6 are provided in a plurality of stages in the direction, and are fixed at appropriate intervals. In addition, as shown in FIG. 2a, a large number of fuel pins 1 are formed by partition walls 7 each having a regular hexagonal cross section and formed by an inner region I.
And the outer area II. Further, the fuel pin 1 in the outer region II is surrounded by an outer cylinder 8 whose upper and lower ends are open, and the lower end opening of the outer cylinder 8 is provided with a flow rate adjusting orifice 9 in the outer region II.

上記燃料集合体の炉心圧損は、これまでの実験及び解析
結果によれば既に説明した第５図に示す構造の燃料集合
体が3.5Kg/cm2であるのに比べて1.5Kg/cm2と大幅に低減
される。このため冷却材を循環する循環ポンプの動力が
低減し、冷却材が炉心を通過する循環系をスムーズに循
環するようになる。Core pressure loss of the fuel assembly, previous experiments and analyzes a fuel assembly having the structure shown in FIG. 5 already described, according to the result of the 1.5 Kg / cm 2 as compared to a 3.5 Kg / cm 2 Significantly reduced. Therefore, the power of the circulation pump that circulates the coolant is reduced, and the coolant smoothly circulates in the circulation system that passes through the core.

また、各燃料ピン１はグリッド６により固定されてい
て、燃料ピン１と隔壁７及び外筒８との間隔を適当に離
間して保持するので、原子炉運転中に燃料集合体が膨張
しても、それぞれの間に相互干渉がほとんど生じないの
で、隔壁７及び外筒８が相互干渉によって変形すること
がなく、長期使用でき、期間当りの放射性廃棄物の量は
少量で済むことになる。Further, since each fuel pin 1 is fixed by the grid 6 and the fuel pin 1 and the partition wall 7 and the outer cylinder 8 are appropriately separated and held, the fuel assembly expands during the operation of the reactor. However, since mutual interference hardly occurs between them, the partition wall 7 and the outer cylinder 8 are not deformed by mutual interference, can be used for a long time, and the amount of radioactive waste per period can be small.

更に、流量調節オリフィス９の調節により炉心における
上に述べた領域Ｉ及び領域IIを流れる冷却材の流量が適
当に配分できるため、燃料の燃焼特性は良好となる。Further, the flow rate of the coolant flowing through the above-mentioned region I and region II in the core can be appropriately distributed by adjusting the flow rate adjusting orifice 9, so that the fuel combustion characteristic becomes good.

更にまた、上記燃料集合体を例えば電力100MW程度以下
を出力する発電用原子炉の小型炉心に使用した場合、燃
料破損率を0.01％とすると破損燃料ピンは高々１本程度
であり、充分許容できるために、交換の必要はない。Furthermore, when the fuel assembly is used for a small core of a power generation reactor that outputs, for example, an electric power of about 100 MW or less, if the fuel breakage rate is 0.01%, the number of broken fuel pins is at most about 1, which is sufficiently acceptable. Therefore, there is no need for replacement.

因みに上記したような小型炉心を備えた発電用原子炉に
ついて簡単に説明すると、第３図において原子炉容器11
内に環状の径方向反射体12が冷却材13中に配置されて固
定されている。更に上記燃料集合体の外筒８の上下両端
が２つの軸方向反射体14a,14bに挾まれて接合され、軸
方向反射体14aが連結管15の下端に接合され、外筒８は
２つの軸方向反射体14a,14b及び連結管15と一緒に径方
向反射体12の環内を貫通可能であって、連結管15は外筒
８が径方向反射体12の管内を貫通してもその上端が原子
炉容器11外に突出する長さを有し、原子炉容器11の上端
開口部を封栓しかつ外部への放射線の漏洩を防止する遮
蔽プラグ16を気密に貫通して原子炉容器11内に挿入され
ている。また、２つの軸方向反射体14a,14bには共に軸
方向に冷却材流路が形成され、連結管15の上部には冷却
材流通孔19が開けられ、冷却材13は例えば連結管15内に
設けられた循環ポンプ20により、あるいは自然循環によ
り外筒８の内部、即ち炉心10を通って連結管15上部の冷
却材流通孔19を通って原子炉容器11内を循環するように
なっている。この原子炉の出力は、径方向反射体12に対
する炉心10の挿入位置により定まり、第４図ａの様に炉
心10が２つの軸方向反射体14a,14bと径方向反射体12と
によって囲まれるようになると臨界に達し、更に炉心10
が径方向反射体12の中央に挿入される（第４図ｂ）と最
大となり、次いで原子炉の出力は徐々に減少し、炉心10
が径方向反射体12を完全に通過する（第４図ｃ）と炉が
スクラムされるようになっている。炉心で発生する熱
は、例えば連結管15中に配設されたヒートパイプ17を介
してその上端から外部に取出されるようになっている。Incidentally, a nuclear reactor for power generation equipped with the above-described small core will be briefly described. In FIG.
An annular radial reflector 12 is disposed and fixed in a coolant 13 therein. Further, the upper and lower ends of the outer cylinder 8 of the fuel assembly are sandwiched and joined by the two axial reflectors 14a and 14b, the axial reflector 14a is joined to the lower end of the connecting pipe 15, and the outer cylinder 8 has two The axial reflectors 14a, 14b and the connecting pipe 15 can pass through the inside of the radial reflector 12 together with the connecting pipe 15 even if the outer cylinder 8 passes through the inside of the radial reflector 12. The upper end has a length projecting to the outside of the reactor vessel 11, seals the upper end opening of the reactor vessel 11 and hermetically penetrates a shield plug 16 that prevents leakage of radiation to the outside, and the reactor vessel Inserted within 11. A coolant passage is formed in the axial direction in both of the two axial reflectors 14a and 14b, a coolant passage hole 19 is formed in the upper portion of the connecting pipe 15, and the coolant 13 is, for example, in the connecting pipe 15. A circulation pump 20 provided in the inside of the outer cylinder 8 is used to circulate in the reactor vessel 11 through the inside of the outer cylinder 8, that is, through the core 10, through the coolant circulation hole 19 in the upper portion of the connecting pipe 15. There is. The output of this reactor is determined by the insertion position of the core 10 with respect to the radial reflector 12, and the core 10 is surrounded by the two axial reflectors 14a and 14b and the radial reflector 12 as shown in FIG. 4a. It reached criticality and the core 10
Is maximized when it is inserted in the center of the radial reflector 12 (Fig. 4b), then the power of the reactor gradually decreases, and the core 10
Completely traverses the radial reflector 12 (Fig. 4c) so that the furnace is scrammed. The heat generated in the core is taken out from the upper end through a heat pipe 17 arranged in the connecting pipe 15, for example.

例えば出力300MW以下の小型の上記液体金属冷却高速炉
に上記実施例の燃料集合体を使用し、冷却材13に溶融金
属ナトリウム（Na）またはナック（NaK）等の液体金属
を使用する場合、冷却材ボイド係数は負であるため、燃
料集合体を空気中で組立てる段階での臨界に対する安全
性は確保できる。また、出力10MWの炉心10に上記実施例
の燃料集合体を使用し、炉心10が径方向反射体12に挿入
されている場合と引抜かれた場合の反射体ワースは18％
△K/Kであり、これは従来の大型炉心の制御棒ワース
（通常７〜８％△K/K）に比べてかなり大きい。従って
上記実施例の燃料集合体では余剰反応度を大きくでき
る。また、１年間原子炉を運転した場合の燃焼欠損反応
度は約2.5％△K/Kであるため、大まかな目安として燃焼
寿命は約７年となることが期待できる。For example, when the fuel assembly of the above-mentioned embodiment is used for the small-sized liquid metal-cooled fast reactor having an output of 300 MW or less, and liquid metal such as molten metal sodium (Na) or nack (NaK) is used as the coolant 13, cooling is performed. Since the material void coefficient is negative, safety against criticality can be secured at the stage of assembling the fuel assembly in air. Further, the fuel assembly of the above-mentioned embodiment is used for the core 10 having an output of 10 MW, and the reflector worth when the core 10 is inserted into the radial reflector 12 and when it is pulled out is 18%.
ΔK / K, which is considerably larger than the conventional large rod control rod worth (usually 7-8% ΔK / K). Therefore, the excess reactivity can be increased in the fuel assembly of the above embodiment. In addition, since the combustion defect reactivity is about 2.5% ΔK / K when the reactor is operated for 1 year, it is expected that the combustion life will be about 7 years as a rough guide.

この様にして寿命に達した燃料集合体は、崩壊熱の減衰
した後に連結管15ごとに引抜かれ、燃料交換が行なわれ
る。After the decay heat decays, the fuel assemblies that have reached the end of their life are withdrawn for each connecting pipe 15, and the fuel is exchanged.

以上にこの発明の燃料集合体の１例を示したが、この発
明の燃料集合体は、例えば炉心規模がある程度大きい場
合には、第２図ｂに示すように制御棒案内管18を設け、
制御棒を挿入できる構造とすることもできるなど、使用
する原子炉の種類及び規模等に応じて種々の変形が可能
である。One example of the fuel assembly of the present invention has been described above. The fuel assembly of the present invention is provided with a control rod guide pipe 18 as shown in FIG. 2B when the core size is large to some extent.
Various modifications are possible depending on the type and scale of the nuclear reactor used, such as a structure in which control rods can be inserted.

＜発明の効果＞ 以上の説明から明らかな様に、この発明の燃料集合体は
炉心圧損が小さく、炉心を通過する冷却材は流量調節手
段により流量を調節されて複数領域に配分されるため径
方向の出力分布を平坦化できる。また、外筒と燃料ピン
及び隔壁と燃料ピンの相互干渉がほとんどないので、外
筒、隔壁等が変形するようなことも生じないから、長期
間の原子炉運転が可能となる。しかも燃料集合体を一括
交換するような使用法が可能であるので、従来の回転プ
ラグ、燃料交換機及び燃料出入機といった燃料交換シス
テムを必要としないし、繁雑な燃料交換作業を省略でき
る。この発明の燃料集合体は、従って、出力規模の小さ
い小型の高速炉用として極めて有効である。<Effects of the Invention> As is clear from the above description, the fuel assembly of the present invention has a small core pressure loss, and the coolant passing through the core has its flow rate adjusted by the flow rate adjusting means and is distributed to a plurality of regions. The output distribution in the direction can be flattened. Further, since there is almost no mutual interference between the outer cylinder and the fuel pin and between the partition wall and the fuel pin, the outer cylinder, the partition wall, and the like are not deformed, so that the reactor operation can be performed for a long time. In addition, since it is possible to use the fuel assemblies in a batch exchange, there is no need for a conventional fuel exchange system such as a rotary plug, a fuel exchange, and a fuel inlet / outlet, and complicated fuel exchange work can be omitted. Therefore, the fuel assembly of the present invention is extremely effective for a small fast reactor having a small output scale.

【図面の簡単な説明】[Brief description of drawings]

第１図は、この発明の燃料集合体の１例を概略的に示す
縦断面図、第２図ａは、第１図の燃料集合体の１部省略
横断面図、第２図ｂは、この発明の燃料集合体の別の１
例を示す１部省略横断面図、第３図は、第１図の燃料集
合体を使用した液体金属冷却高速炉の１例を示す１部省
略縦断面図、第４図a,b,cはそれぞれ第３図の液体金属
冷却高速炉が臨界出力、最大出力、スクラムにある時の
炉心の配置を示す説明図、第５図は、従来の燃料集合体
の１例を示す説明図、第６図は、従来の燃料集合体の別
の１例を示す概略縦断面図である。 １……燃料ピン、６……グリッド、７……隔壁、８……
外筒、９……流量調節オリフィス、10……炉心。FIG. 1 is a longitudinal sectional view schematically showing an example of a fuel assembly of the present invention, FIG. 2a is a partially omitted lateral sectional view of the fuel assembly of FIG. 1, and FIG. Another one of the fuel assemblies of the present invention
An example of a partly omitted cross-sectional view is shown, and FIG. 3 is a partly omitted longitudinal cross-sectional view showing an example of a liquid metal-cooled fast reactor using the fuel assembly of FIG. 1, a, b, c. 3 is an explanatory view showing the arrangement of the core when the liquid metal cooled fast reactor of FIG. 3 is in the critical output, maximum output, and scram, and FIG. 5 is an illustration showing an example of a conventional fuel assembly, FIG. 6 is a schematic vertical cross-sectional view showing another example of a conventional fuel assembly. 1 ... Fuel pin, 6 ... Grid, 7 ... Partition, 8 ...
Outer cylinder, 9 ... Flow rate control orifice, 10 ... Reactor core.

Claims (2)

【特許請求の範囲】[Claims] 【請求項１】上端と下端が開口した外筒内に多数の燃料
ピンを配置するとともに、これらの燃料ピンを互いに所
定間隔離間して固定するグリッドを燃料ピン軸方向に複
数段設け、前記多数の燃料ピンを内側領域と外側領域と
に仕切る隔壁を前記外筒内に該外筒と同軸的に配設し、
前記外筒の下端開口部の前記外側領域部分に冷却材流量
調節手段を設けたことを特徴とする燃料集合体。1. A plurality of fuel pins are arranged in an outer cylinder having an open upper end and a lower end, and a grid for fixing the fuel pins at a predetermined interval is provided in a plurality of stages in the axial direction of the fuel pin. A partition wall for partitioning the fuel pin into an inner region and an outer region is disposed in the outer cylinder coaxially with the outer cylinder,
A fuel assembly, wherein a coolant flow rate adjusting means is provided in the outer region portion of the lower end opening of the outer cylinder. 【請求項２】前記冷却材流量調節手段が流量調節オリフ
ィスからなる請求項１記載の燃料集合体。2. The fuel assembly according to claim 1, wherein the coolant flow rate adjusting means comprises a flow rate adjusting orifice.
JP1028422A 1989-02-07 1989-02-07 Fuel assembly Expired - Lifetime JPH079473B2 (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
JP1028422A JPH079473B2 (en) 1989-02-07 1989-02-07 Fuel assembly
FR9001306A FR2642887B1 (en) 1989-02-07 1990-02-05 FUEL ASSEMBLY

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP1028422A JPH079473B2 (en) 1989-02-07 1989-02-07 Fuel assembly

Publications (2)

Publication Number Publication Date
JPH02206797A JPH02206797A (en) 1990-08-16
JPH079473B2 true JPH079473B2 (en) 1995-02-01

Family

ID=12248222

Family Applications (1)

Application Number Title Priority Date Filing Date
JP1028422A Expired - Lifetime JPH079473B2 (en) 1989-02-07 1989-02-07 Fuel assembly

Country Status (2)

Country Link
JP (1) JPH079473B2 (en)
FR (1) FR2642887B1 (en)

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20120121058A1 (en) * 2009-07-31 2012-05-17 Tokyo Institute Of Technology Core of nuclear reactor and nuclear reactor
JP5302156B2 (en) * 2009-09-29 2013-10-02 日立Ｇｅニュークリア・エナジー株式会社 Fast breeder reactor core

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR1276233A (en) * 1960-03-14 1961-11-17 Gen Nuclear Engineering Co Improvements to nuclear reactors
JPS5224199B2 (en) * 1972-02-16 1977-06-29
UST939002I4 (en) * 1973-04-18 1975-10-07 Epithermal nuclear reactor
DE2715067A1 (en) * 1977-04-04 1978-10-12 Iljunin FOCUS PACKAGE FOR NUCLEAR REACTORS WITH FAST NEUTRONS

Also Published As

Publication number Publication date
FR2642887B1 (en) 1994-04-15
FR2642887A1 (en) 1990-08-10
JPH02206797A (en) 1990-08-16

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