JPH0316633B2 - - Google Patents
Info
- Publication number
- JPH0316633B2 JPH0316633B2 JP60187453A JP18745385A JPH0316633B2 JP H0316633 B2 JPH0316633 B2 JP H0316633B2 JP 60187453 A JP60187453 A JP 60187453A JP 18745385 A JP18745385 A JP 18745385A JP H0316633 B2 JPH0316633 B2 JP H0316633B2
- Authority
- JP
- Japan
- Prior art keywords
- rod assembly
- coolant
- control rod
- fuel rod
- fuel
- 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
Links
- 239000002826 coolant Substances 0.000 claims description 37
- 239000000446 fuel Substances 0.000 claims description 37
- 239000012530 fluid Substances 0.000 claims description 4
- 238000011144 upstream manufacturing Methods 0.000 claims description 3
- 230000001681 protective effect Effects 0.000 claims description 2
- 230000000712 assembly Effects 0.000 description 7
- 238000000429 assembly Methods 0.000 description 7
- 230000001105 regulatory effect Effects 0.000 description 4
- 229910052751 metal Inorganic materials 0.000 description 3
- 239000002184 metal Substances 0.000 description 3
- 238000010586 diagram Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- DGAQECJNVWCQMB-PUAWFVPOSA-M Ilexoside XXIX Chemical compound C[C@@H]1CC[C@@]2(CC[C@@]3(C(=CC[C@H]4[C@]3(CC[C@@H]5[C@@]4(CC[C@@H](C5(C)C)OS(=O)(=O)[O-])C)C)[C@@H]2[C@]1(C)O)C)C(=O)O[C@H]6[C@@H]([C@H]([C@@H]([C@H](O6)CO)O)O)O.[Na+] DGAQECJNVWCQMB-PUAWFVPOSA-M 0.000 description 1
- 239000006096 absorbing agent Substances 0.000 description 1
- 230000006866 deterioration Effects 0.000 description 1
- 238000005192 partition Methods 0.000 description 1
- 230000035939 shock Effects 0.000 description 1
- 229910052708 sodium Inorganic materials 0.000 description 1
- 239000011734 sodium Substances 0.000 description 1
- 230000008646 thermal stress Effects 0.000 description 1
- 239000010409 thin film Substances 0.000 description 1
Classifications
-
- 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
Landscapes
- Structure Of Emergency Protection For Nuclear Reactors (AREA)
- Heat-Exchange Devices With Radiators And Conduit Assemblies (AREA)
Description
【発明の詳細な説明】
「産業上の利用分野」
本発明は炉心燃料集合体と制御棒集合体の双方
から放出される冷却材の温度差を軽減させた高速
増殖炉に関する。DETAILED DESCRIPTION OF THE INVENTION "Field of Industrial Application" The present invention relates to a fast breeder reactor in which the temperature difference between coolant discharged from both a core fuel assembly and a control rod assembly is reduced.
「従来の技術」
高速増殖炉の炉心には、６角柱状の制御棒集合
体が多数収容されているが、これらの所定箇所に
は、６角柱状の制御棒集合体がそれら６方の側面
をそれぞれ１体ずつの燃料棒集合体に取り囲まれ
るようにして配置されている。``Prior art'' The core of a fast breeder reactor accommodates a large number of hexagonal columnar control rod assemblies. are arranged so that they are each surrounded by one fuel rod assembly.
第５図は、このうち１体の制御棒集合体１と、
これを取り囲む６体のうちの２体の燃料棒集合体
２を表わしたものである。それぞれの集合体１，
２は流量調節オリフイス３，４から冷却材（ナト
リウム）を取り入れ、内部の冷却を行つた後、上
部に配置された出口５，６からこれらを流出させ
るようになつている。ところが制御棒集合体１か
ら流出される冷却材の温度が燃料棒集合体２のそ
れとかなり異なるので、炉心出口近傍で温度ゆら
ぎの現象（サーマルストライピング）が発生す
る。 FIG. 5 shows one control rod assembly 1,
Two of the six fuel rod assemblies 2 surrounding this are shown. Each aggregate 1,
2 takes in coolant (sodium) from flow rate regulating orifices 3 and 4, cools the inside, and then flows out from outlets 5 and 6 located at the top. However, since the temperature of the coolant flowing out from the control rod assembly 1 is considerably different from that of the fuel rod assembly 2, a phenomenon of temperature fluctuation (thermal striping) occurs near the core exit.
第６図はこの現象を説明するためのものであ
る。燃料棒集合体２の出口から流出する冷却材の
温度THは、制御棒集合体１の冷却材の温度TCよ
りもかなり高く、その温度差は150度Ｃ程度にも
達する。このためこれら冷却材の混合場所で乱流
が生じ、約２Hz程度の温度のゆらぎが発生する。 FIG. 6 is for explaining this phenomenon. The temperature T H of the coolant flowing out from the outlet of the fuel rod assembly 2 is considerably higher than the temperature T C of the coolant in the control rod assembly 1, and the temperature difference reaches about 150 degrees Celsius. As a result, turbulent flow occurs where these coolants are mixed, and temperature fluctuations of about 2 Hz occur.
「発明が解決しようとする問題点」
燃料棒集合体２等の出口の上方には炉上部機構
（図示せず）が配置されている。従つて、この温
度のゆらぎによつて炉上部機構の強度部材が温度
変化を繰り返すことになる。高速増殖炉のプラン
ト寿命を30年とすれば、この温度変化の繰り返し
回数は1.5×109以上にもなり、熱疲労による強度
部材の劣化が問題となる。"Problems to be Solved by the Invention" A reactor upper mechanism (not shown) is disposed above the outlet of the fuel rod assembly 2 and the like. Therefore, this temperature fluctuation causes the strength member of the furnace upper mechanism to undergo repeated temperature changes. If the plant life of a fast breeder reactor is 30 years, the number of repetitions of this temperature change will be more than 1.5×10 9 , and deterioration of strength members due to thermal fatigue becomes a problem.
そこで、炉心上部機構の強度部材を特殊な金属
の薄膜で被覆して、温度衝撃を緩和する提案が行
われている。ところがこの提案によれば、強度部
材の加工が複雑となるという問題がある。 Therefore, proposals have been made to coat the strength members of the upper core structure with a special metal thin film to alleviate the temperature shock. However, according to this proposal, there is a problem that processing of the strength member becomes complicated.
そこで本発明の目的は、炉心上部機構の強度部
材そのものの受ける熱応力を十分減少させること
のできる高速増殖炉を提供することにある。 SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a fast breeder reactor that can sufficiently reduce the thermal stress applied to the strength members of the core upper mechanism itself.
「問題点を解決するための手段」
本発明では、温度差の存在する２経路の冷却材
の一部を予め炉心出口手前で混合し、炉心出口か
ら流出する冷却材の温度差を十分小さくして温度
ゆらぎの現象による金属疲労の減少を図る。この
ために、制御棒集合体の上下動自在に配置された
イナーダクト（INNER DUCT）の外側を覆う
固定されたアウターダクト（OUTER DUCT）
を構成する保護管上部壁面と、この制御棒集合体
の周囲を取り囲む形で配置される燃料棒集合体の
上部遮蔽体の壁面のそれぞれ対向する位置に、冷
却材の一部の燃料棒から保護管の上部領域に流入
させるための開口部を設ける。通常の場合、燃料
棒集合体内の冷却材の方が制御棒集合体のそれよ
りも圧力が高いのでこれにより燃料棒集合体の冷
却材の一部が開口部から制御棒集合体内の上部領
域に流入するが、燃料棒集合体の上部遮蔽体の内
壁面に流体流出誘導片を設け、これによつて制御
棒集合体の保護管上部に積極的に冷却材を流入さ
せる。"Means for Solving the Problem" In the present invention, a portion of the coolant in two paths with a temperature difference is mixed in advance before the reactor core exit, so that the temperature difference between the coolant flowing out from the reactor core exit is sufficiently reduced. This aims to reduce metal fatigue caused by temperature fluctuation phenomena. For this purpose, a fixed outer duct (OUTER DUCT) is installed that covers the outside of the inner duct (INNER DUCT), which is arranged so that the control rod assembly can move up and down.
The upper wall of the protection tube constituting the control rod assembly and the wall of the upper shield of the fuel rod assembly, which is arranged to surround the control rod assembly, are installed at opposite positions to protect the coolant from some of the fuel rods. An opening is provided for entry into the upper region of the tube. Normally, the pressure in the fuel rod assembly coolant is higher than that in the control rod assembly, which allows some of the fuel rod assembly coolant to flow through the opening into the upper region of the control rod assembly. However, a fluid outflow guide piece is provided on the inner wall surface of the upper shield of the fuel rod assembly, thereby actively causing the coolant to flow into the upper part of the protection tube of the control rod assembly.
「実施例」 以下実施例につき本発明を詳細に説明する。"Example" The present invention will be explained in detail with reference to Examples below.
第１図は第５図に対応したもので、本実施例の
高速増殖炉の炉心に配置された制御棒集合体とこ
れに隣り合つて配置された燃料棒集合体の一部を
表わしたものである。制御棒集合体１１の保護管
上部には、６面にそれぞれ１つずつ直径約３cmの
孔１２が開けられている。燃料棒集合体１３の上
部遮蔽体にも制御棒集合体の孔１２と対向する部
位に同様な大きさの孔１４が開けられている。 FIG. 1 corresponds to FIG. 5 and shows a control rod assembly arranged in the core of the fast breeder reactor of this embodiment and a part of the fuel rod assembly arranged adjacent to it. It is. In the upper part of the protection tube of the control rod assembly 11, holes 12 each having a diameter of about 3 cm are bored, one on each of six sides. A hole 14 of similar size is also formed in the upper shield of the fuel rod assembly 13 at a portion facing the hole 12 in the control rod assembly.
第２図は本実施例の燃料集合体における後述す
る誘導片を除いた状態の断面を参考的に表わした
ものである。燃料棒集合体１３の下部（第５図参
照）に配置された流量調節オリフイスからこの燃
料棒集合体１３内部に流入してきた冷却材１５
は、その約12分の11の冷却材１５Ａがそのまま炉
心出口を通つて流出する。これに対して、残りの
冷却材１５Ｂは、孔１４および１２を介して制御
棒集合体１１の上部領域内に流入する。１体の燃
料棒集合体１３から制御棒集合体１１の内部に流
入する冷却材１５Ｂの割合の調整や、この流入に
よる制御棒集合体１１自体の冷却材の取り込みの
調整は、両孔１２，１４の大きさや前記した流量
調節オリフイス３，４の大きさによつて予め調整
することができる。 FIG. 2 shows, for reference, a cross section of the fuel assembly of this embodiment with the guide piece, which will be described later, removed. Coolant 15 flows into the fuel rod assembly 13 from a flow rate regulating orifice located at the lower part of the fuel rod assembly 13 (see FIG. 5).
In this case, about 11/12th of the coolant 15A flows out directly through the core outlet. In contrast, the remaining coolant 15B flows into the upper region of the control rod assembly 11 via holes 14 and 12. Adjustment of the ratio of coolant 15B flowing into the control rod assembly 11 from one fuel rod assembly 13 and adjustment of the intake of coolant into the control rod assembly 11 itself due to this inflow are performed through both holes 12, 14 and the sizes of the flow rate regulating orifices 3 and 4 described above.
第３図は、制御棒集合体１１を取り囲んだ６体
の燃料棒集合体１３による冷却材１５Ｂの流入状
況を表わしたものである。制御棒集合体１１に
は、燃料棒集合体１３の１体分に流れる冷却材１
５の約２分の１の冷却材が流入する。このとき、
制御棒集合体１１の前記した上部領域では、約
150度Ｃの温度差の２種類の冷却材が混合し一種
の乱流状態を発生させる。しかしながら、制御棒
集合体１１は炉上部機構と異なり永久構造物では
ないので、温度のゆらぎによつて保護管部分の金
属が疲労しても、燃料棒集合体の交換等の際にこ
れを交換することが可能である。 FIG. 3 shows how the coolant 15B flows into the six fuel rod assemblies 13 surrounding the control rod assembly 11. The control rod assembly 11 has a coolant 1 flowing through one of the fuel rod assemblies 13.
Approximately 1/2 of 5 coolant flows in. At this time,
In the above-mentioned upper region of the control rod assembly 11, approximately
Two types of coolant with a temperature difference of 150 degrees Celsius mix, creating a kind of turbulent flow condition. However, unlike the upper reactor mechanism, the control rod assembly 11 is not a permanent structure, so even if the metal in the protective tube part fatigues due to temperature fluctuations, it must be replaced when the fuel rod assembly is replaced. It is possible to do so.
制御棒集合体１１の出口からは、このようにし
て一旦混合されて温度の平均化された冷却材が流
出し、燃料棒集合体１３から流出する冷却材と炉
心出口近傍で更に混合される。この後者の混合時
には混合される冷却材の温度差がずつと小さくな
つている。従つて、この混合は比較的スムーズに
行われ、温度ゆらぎもほとんど生じない。すなわ
ちこれにより炉上部機構が熱的な疲労を受けるこ
とはほとんどなくなる。 The coolant that has been mixed and whose temperature has been averaged in this manner flows out from the exit of the control rod assembly 11, and is further mixed with the coolant flowing out from the fuel rod assembly 13 near the core exit. During this latter mixing, the temperature difference between the coolants being mixed is gradually becoming smaller. Therefore, this mixing is performed relatively smoothly and there is almost no temperature fluctuation. In other words, as a result, the upper furnace mechanism is hardly subjected to thermal fatigue.
第４図は、本実施例の燃料集合体の断面を表わ
したものである。燃料棒集合体は制御棒集合体に
比べてその内部がより高温となる。このため、内
部における冷却材の流量は、制御棒集合体のそれ
よりも多くなるように流量調節オリフイス４（第
５図参照）の調節が行われている。従つて、両集
合体の隔壁に孔が開けられた場合には、燃料棒集
合体の方から制御棒集合体の方に冷却材の流入が
自然に行われることになる。本実施例の高速増殖
炉では、この冷却材の流入を十分に行わせるため
に、制御棒集合体１３の孔１４の下流側の端部を
基部として上流側に突出した誘導片１７を設けて
いる。この誘導片１７によつて冷却材１５の一部
が強制的に孔１４方向にその向きを変えられ、制
御棒集合体内部への流入量を増加させることがで
きる。 FIG. 4 shows a cross section of the fuel assembly of this example. The internal temperature of the fuel rod assembly is higher than that of the control rod assembly. For this reason, the flow rate regulating orifice 4 (see FIG. 5) is adjusted so that the flow rate of the coolant inside the control rod assembly is greater than that of the control rod assembly. Therefore, if holes are made in the partition walls of both assemblies, the coolant will naturally flow from the fuel rod assembly to the control rod assembly. In the fast breeder reactor of this embodiment, in order to ensure sufficient inflow of this coolant, a guide piece 17 is provided that protrudes upstream from the downstream end of the hole 14 of the control rod assembly 13 as a base. There is. This guide piece 17 forcibly changes the direction of a portion of the coolant 15 toward the hole 14, making it possible to increase the amount of flow into the control rod assembly.
「発明の効果」
以上説明したように、本発明によれば保護管の
上部や上部遮蔽体といつた中性子吸収体や燃料の
格納スペース外の部分を使用して冷却材の混合を
行うこととしたので、制御棒集合体や燃料棒集合
体の定期的な交換により熱疲労の問題を避けるこ
とができ、しかも原子炉の基本構造をなんら変更
することなく、簡易に実施することができるとい
う長所がある。また、本発明の高速増殖炉では燃
料棒集合体の上部遮蔽体の内壁面に、開口部の上
流側から流れてくる冷却材をこの開口部を経て保
護管の上部領域へと流出させるための流体流出誘
導片が設けられているので、燃料集合体の方から
制御棒集合体の方に冷却材を流入させるための孔
を比較的小さく設定した場合でも、冷却材の流入
を十分確保することができるという効果がある。"Effects of the Invention" As explained above, according to the present invention, it is possible to mix the coolant using the neutron absorber such as the upper part of the protection tube and the upper shield, and the part outside the fuel storage space. Therefore, the problem of thermal fatigue can be avoided by periodically replacing control rod assemblies and fuel rod assemblies, and the advantage is that it can be easily implemented without changing the basic structure of the reactor. There is. In addition, in the fast breeder reactor of the present invention, the inner wall surface of the upper shield of the fuel rod assembly is provided with a hole for allowing the coolant flowing from the upstream side of the opening to flow out through the opening into the upper region of the protection tube. Since a fluid outflow guiding piece is provided, sufficient inflow of coolant can be ensured even if the hole for allowing coolant to flow from the fuel assembly to the control rod assembly is set relatively small. It has the effect of being able to
第１図は本発明の一実施例における制御棒集合
体およびこれに隣接して配置された燃料棒集合体
の一部を示す斜視図、第２図は燃料棒集合体の上
部管壁部分を示す断面図、第３図は、制御棒集合
体とこれを取り囲んだ燃料棒集合体の配置図、第
４図は本発明の一変形例としての燃料棒集合体の
上部管壁部分を示す断面図、第５図は従来の制御
棒集合体およびこれに隣接して配置された燃料棒
集合体の一部を示す斜視図、第６図は炉心出口近
傍で冷却材による温度ゆらぎ（サーマルストライ
ピング）の発生する原理を示した説明図である。
１１……制御棒集合体、１２，１４……孔、１
３……燃料棒集合体、１５……冷却材、１７……
誘導片。
FIG. 1 is a perspective view showing a control rod assembly and a part of a fuel rod assembly arranged adjacent thereto in one embodiment of the present invention, and FIG. 2 is a perspective view showing an upper tube wall portion of the fuel rod assembly. 3 is a layout diagram of a control rod assembly and a fuel rod assembly surrounding it, and FIG. 4 is a sectional view showing an upper tube wall portion of a fuel rod assembly as a modified example of the present invention. Figure 5 is a perspective view showing a part of a conventional control rod assembly and a fuel rod assembly placed adjacent to it, and Figure 6 shows temperature fluctuations caused by coolant near the core exit (thermal striping). FIG. 2 is an explanatory diagram showing the principle of generation of 11... Control rod assembly, 12, 14... Hole, 1
3... Fuel rod assembly, 15... Coolant, 17...
Guide piece.
Claims (1)
棒集合体の保護管の周囲を取り囲む形で配置され
る燃料棒集合体の上部遮蔽体の壁面のそれぞれ対
向する位置に、冷却材の一部を燃料棒集合体から
前記保護管の上部領域に流入させるための開口部
が設けられ、燃料棒集合体の上部遮蔽体の内壁面
には、前記開口部の上流側から流れてくる冷却材
をこの開口部を経て前記保護管の上部領域へと流
出させるための流体流出誘導片が設けられている
ことを特徴とする高速増殖炉。1 A portion of the coolant is placed at opposing positions on the upper side of the protection tube of the control rod assembly and the wall surface of the upper shield of the fuel rod assembly, which is arranged to surround the protection tube of the control rod assembly. An opening is provided for allowing the coolant to flow from the fuel rod assembly into the upper region of the protective tube, and the inner wall surface of the upper shield of the fuel rod assembly is provided with a coolant flowing from the upstream side of the opening. A fast breeder reactor characterized in that a fluid outflow guiding piece is provided for causing the fluid to flow out through the opening into the upper region of the protection tube.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP60187453A JPS6247589A (en) | 1985-08-28 | 1985-08-28 | Fast breeder reactor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP60187453A JPS6247589A (en) | 1985-08-28 | 1985-08-28 | Fast breeder reactor |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS6247589A JPS6247589A (en) | 1987-03-02 |
| JPH0316633B2 true JPH0316633B2 (en) | 1991-03-06 |
Family
ID=16206340
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP60187453A Granted JPS6247589A (en) | 1985-08-28 | 1985-08-28 | Fast breeder reactor |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS6247589A (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2809700B2 (en) * | 1989-05-25 | 1998-10-15 | 株式会社東芝 | Core structure for fast breeder reactor |
| CN1070424C (en) * | 1995-07-24 | 2001-09-05 | 三星电子株式会社 | Image forming system with device for confirming number of sheets |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5786787A (en) * | 1980-11-20 | 1982-05-29 | Tokyo Shibaura Electric Co | Nuclear reactor |
| JPS61230079A (en) * | 1985-04-05 | 1986-10-14 | 株式会社日立製作所 | Fuel-control rod aggregate for fast reactor |
-
1985
- 1985-08-28 JP JP60187453A patent/JPS6247589A/en active Granted
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5786787A (en) * | 1980-11-20 | 1982-05-29 | Tokyo Shibaura Electric Co | Nuclear reactor |
| JPS61230079A (en) * | 1985-04-05 | 1986-10-14 | 株式会社日立製作所 | Fuel-control rod aggregate for fast reactor |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS6247589A (en) | 1987-03-02 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP2642761B2 (en) | Fuel bundles for boiling water reactors | |
| US4235669A (en) | Nuclear reactor composite fuel assembly | |
| JPH04258792A (en) | Guiding apparatus for control rod cluster | |
| EP2850617B1 (en) | Fuel bundle for a liquid metal cooled nuclear reactor | |
| US4557892A (en) | Nuclear fuel element | |
| JPH0316633B2 (en) | ||
| JP3079877B2 (en) | Fuel assembly | |
| JP5443199B2 (en) | Fast breeder reactor core structure | |
| JP2933438B2 (en) | Control rod assembly vertical guidance system for nuclear reactor | |
| US4588549A (en) | Automatic coolant flow control device for a nuclear reactor assembly | |
| JP2504514B2 (en) | Reactor fuel assembly | |
| JP2972162B2 (en) | Furnace wall cooling protection structure of fast reactor | |
| JPH07104091A (en) | Vessel wall cooling structure for reactor vessel | |
| JP2960381B2 (en) | Compartment-type irradiated fuel assembly | |
| JPH0512798Y2 (en) | ||
| JPH07167979A (en) | Vessel wall cooling structure of reactor vessel | |
| JP2928516B2 (en) | Fuel assembly | |
| JPH05157869A (en) | Fuel assembly | |
| JPH08136687A (en) | Cooling structure for vessel wall of reactor vessel | |
| JPH11133172A (en) | Internal structure of fast breeding reactor | |
| CN117747142A (en) | High density control rod assembly and absorption rod thereof | |
| JPH0413678B2 (en) | ||
| JPS59128481A (en) | Upper mechanism for reactor core | |
| JPH02102486A (en) | Fuel assembly and water rod | |
| JPS6410797B2 (en) |