JPH01269086A - fuel assembly - Google Patents
fuel assemblyInfo
- Publication number
- JPH01269086A JPH01269086A JP63095576A JP9557688A JPH01269086A JP H01269086 A JPH01269086 A JP H01269086A JP 63095576 A JP63095576 A JP 63095576A JP 9557688 A JP9557688 A JP 9557688A JP H01269086 A JPH01269086 A JP H01269086A
- Authority
- JP
- Japan
- Prior art keywords
- fuel rod
- spacer
- rod
- fuel
- length 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.)
- Pending
Links
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
- Hydrogen, Water And Hydrids (AREA)
Abstract
(57)【要約】本公報は電子出願前の出願データであるた
め要約のデータは記録されません。(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明は、燃料集合体に係わり、特に、水、蒸気から成
る二相流領域での流れの圧力損失が水車相流領域での圧
力損失に比べて大きいため生じる炉心の不安定現象を回
避するのに好適な沸騰水型原子炉に用いられる燃料集合
体の構造に関する。[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a fuel assembly, and in particular, the pressure loss of a flow in a two-phase flow region consisting of water and steam is equal to the pressure loss in a water turbine phase flow region. This invention relates to the structure of a fuel assembly used in a boiling water reactor, which is suitable for avoiding core instability phenomena caused by the large size of the reactor.
従来の燃料集合体は、特開昭５８−１１３８９１号公報
、特開昭６２−１７７４８７号公報に記載するように、
燃料棒１．水ロッド２．スペーサ３．チャンネルボック
ス４等より構成される（第２図参照）、この集合体の圧
力損失を低減する方法のひとつに、部分長燃料棒がある
０部分長燃料棒は、特開昭６２−１９４４９４号公報に
示すような構造のもので、長さが普通のものより短くか
つ上端部は切り取った構造となる。そのため、上部端部
の固定方法は、特開昭６２−１７７４８７の水ロンドの
ようにスペーサで固定することが有力である（第３図参
照）。Conventional fuel assemblies are as described in JP-A-58-113891 and JP-A-62-177487,
Fuel rod 1. Water rod 2. Spacer 3. One way to reduce the pressure loss of this assembly, which is composed of channel boxes 4, etc. (see Figure 2), is to use partial length fuel rods. Japanese Patent Application Laid-Open No. 194494/1983 discloses a zero partial length fuel rod. It has a structure as shown in , which is shorter than the ordinary one and has the upper end cut off. Therefore, the most effective method for fixing the upper end is to use a spacer as in the water rondo of Japanese Patent Application Laid-open No. 62-177487 (see FIG. 3).
上記従来技術は、部分長燃料棒上部での圧力損失低減に
ついて考慮されてない。このため、原子炉起動時に自然
循環運転から強制循環運転に切り変わる際の炉心の安定
性余裕が小さいという問題点があった。一般に、炉心の
状態は、燃料集合体内の水車相流領域での圧力損失に比
べて、水、蒸気からなる二相流領域での圧力損失が大き
いほど、不安定な状態に近付く、スペーサの圧力損失が
集合体における全圧力損失に占める割合は、約３０％程
度ある。しかも、この圧力損失は二相流領域で生じるた
めに、炉心の安定性余裕は小さくなる。The above-mentioned conventional technology does not take into account the reduction of pressure loss at the upper part of the part-length fuel rod. For this reason, there was a problem in that there was a small stability margin for the reactor core when switching from natural circulation operation to forced circulation operation at reactor startup. In general, the state of the core approaches an unstable state as the pressure loss in the two-phase flow region consisting of water and steam is greater than the pressure loss in the turbine-phase flow region within the fuel assembly. The loss accounts for about 30% of the total pressure loss in the assembly. Moreover, since this pressure loss occurs in the two-phase flow region, the stability margin of the core becomes small.
第４図に、燃料集合体上部の圧力損失と安定性の指標で
ある減幅比の関係を求めた結果を示す。ここで、減幅比
が１以下であれば、炉心は安定な状態にある。この図よ
り、スペーサの圧力損失を低減することにより、炉心の
安定性が大幅に向上することがわかる。現状の沸騰水型
原子炉の安定性余裕は小さいので、この安定性余裕の増
加は大きな効果がある。FIG. 4 shows the results of determining the relationship between the pressure loss in the upper part of the fuel assembly and the width reduction ratio, which is an index of stability. Here, if the width reduction ratio is 1 or less, the core is in a stable state. From this figure, it can be seen that the stability of the reactor core is significantly improved by reducing the pressure loss of the spacer. Since the stability margin of current boiling water reactors is small, increasing this stability margin has a large effect.
本発明の目的は、部分長燃料棒上端部を支持するスペー
サを低減することにより、炉心の安定性余裕を向上した
燃料集合体構造を低減することにある。An object of the present invention is to reduce the number of spacers that support the upper ends of part-length fuel rods, thereby reducing the fuel assembly structure that improves the stability margin of the reactor core.
上記問題点は１部分長燃料棒の上端部を、上端支持スペ
ーサより下方に位置させることにより達成される（第５
図参照）、ただし、部分長燃料棒の上端部を固定する方
法は第１図、第７図、第８図、第９図に示すように、円
筒管、端栓捧、下方延長丸セルを用いると、部分長燃料
棒の上端部を従来により、固定される。詳細については
実施例で記述する。The above problem can be solved by locating the upper end of the one-part length fuel rod below the upper end support spacer (fifth
However, as shown in Figures 1, 7, 8, and 9, the method for fixing the upper end of a partial length fuel rod is to attach a cylindrical tube, an end stopper, and a downwardly extending round cell. When used, the upper ends of the part-length fuel rods are conventionally secured. Details will be described in Examples.
上記のように部分長燃料棒の上端部を、上端支持スペー
サより下方に位置させると、上端支持スペーサ内での流
路面積が増加するため、圧力損失が低減する。また、第
６図にスペーサ損失の内訳を示すが、スペーサの圧力損
失は第７スペーサ（上から一段目）、第６．第５．第４
．第３．第２、第１の順に小さくなる。ところで、部分
長燃料棒を支持するスペーサは第５、あるいは第６スペ
ーサである。そのため、このスペーサの圧力損失を低減
する効果は大きくなり、全スペーサ損失を効率的に下げ
、安定性の余裕を大幅に増大できることがわかる。When the upper end of the partial length fuel rod is located below the upper end support spacer as described above, the flow passage area within the upper end support spacer increases, thereby reducing pressure loss. Further, Fig. 6 shows the breakdown of spacer loss, and the pressure loss of the spacer is the 7th spacer (first stage from the top), the 6th spacer. Fifth. Fourth
．． Third. It becomes smaller in the order of second and first. By the way, the spacer that supports the part-length fuel rod is the fifth or sixth spacer. Therefore, it can be seen that the effect of reducing the pressure loss of this spacer becomes greater, that the total spacer loss can be efficiently lowered, and the stability margin can be significantly increased.
以下１本発明の詳細を、実施例を用いて説明する。 The details of the present invention will be explained below using examples.
第１図に本発明の一実施例を示す０本実施例では、部分
長燃料棒５の上端面７を部分長燃料棒５の上端部を支持
するスペーサ６より下に位置させ、部分長燃料棒５の上
端面６の上に側面に六８を有する円筒管９を設け、かつ
、この円筒管９と部分長燃料棒５を一体とし、さらに、
この円筒管９をスペーサ６で支持することにより部分長
燃料棒５を固定したものである０部分長燃料棒５は、燃
料棒１よりも軸方向の長さが短がい、係る構造にすると
、作用の項で説明したように、スペーサ６内での流路面
積が増え、スペーサ６の圧力損失が低減するため、安定
性の余裕が大幅に増大する。さらに１本実施例では、部
分長燃料棒５の被覆管を上方に延長して、円筒管９にす
ることも可能である。その場合、製作上の変更はほとん
どなく、信頼性も高いというメリットもある。第７図に
本発明の他の実施例を示すが、本実施例では、側面に穴
を有する円筒管９を部分長燃料棒５上端部にがぶせたも
のである。したがって、本実施例においても、前記実施
例同様、スペーサ６内の流路面積を増大できるので、圧
力損失が低下し、安定性余裕を増大できる。また、本実
施例では、単に円筒管９のキャップを部分長燃料棒５の
上端にがぶせたので、部分長燃料棒５の構造を変える必
要がないというメリットもある。FIG. 1 shows an embodiment of the present invention. In this embodiment, the upper end surface 7 of a part-length fuel rod 5 is located below the spacer 6 that supports the upper end of the part-length fuel rod 5, and the part-length fuel rod 5 is A cylindrical tube 9 having a 68 on the side surface is provided on the upper end surface 6 of the rod 5, and the cylindrical tube 9 and the partial length fuel rod 5 are integrated, and further,
The 0 part length fuel rod 5, in which the part length fuel rod 5 is fixed by supporting this cylindrical tube 9 with the spacer 6, has a shorter axial length than the fuel rod 1, and if it is constructed in this way, As explained in the operation section, the flow path area within the spacer 6 is increased and the pressure loss of the spacer 6 is reduced, so the stability margin is significantly increased. Furthermore, in this embodiment, the cladding tube of the part-length fuel rod 5 can be extended upward to form a cylindrical tube 9. In that case, there are also advantages in that there are almost no changes in production and reliability is high. Another embodiment of the present invention is shown in FIG. 7. In this embodiment, a cylindrical tube 9 having a hole in the side surface is fitted over the upper end of the partial length fuel rod 5. Therefore, in this embodiment as well, as in the previous embodiment, the flow path area within the spacer 6 can be increased, so pressure loss can be reduced and stability margin can be increased. Further, in this embodiment, since the cap of the cylindrical tube 9 is simply placed over the upper end of the partial length fuel rod 5, there is also the advantage that there is no need to change the structure of the partial length fuel rod 5.
第８図に本発明の他の実施例を示す６本実施例では、第
１図の実施例と同様に、部分長燃料棒５の上端面７を部
分長燃料棒５の上端を支持するスペーサ６より下に位置
させ、部分長燃料棒５の上端面７の上に部分長燃料棒５
の外径より細径となる端棒１０を設け、かつ、端棒１０
と部分長燃料棒５を一体とし、さらに、この端棒１０を
スペーサ６で支持することにより部分長燃料棒５を固定
したものである。係る構造にすると、第１図の実施例同
様、スペーサ６内の流路面積を増大できるので、圧力損
失が低下し、安定性余裕を増大できる。また、本実施例
では、部分長燃料棒５の上端構造は従来の燃料棒の上部
端栓の構造と同じになるので、製作上の問題点はなく、
また、製作コストも安価というメリットもある。FIG. 8 shows another embodiment of the present invention. In this embodiment, similarly to the embodiment shown in FIG. 6 and above the upper end surface 7 of the partial length fuel rod 5.
The end rod 10 is provided with a diameter smaller than the outer diameter of the end rod 10.
The part-length fuel rod 5 is integrated with the part-length fuel rod 5, and the end rod 10 is further supported by a spacer 6, thereby fixing the part-length fuel rod 5. With such a structure, as in the embodiment shown in FIG. 1, the area of the flow path within the spacer 6 can be increased, thereby reducing pressure loss and increasing the stability margin. In addition, in this embodiment, the upper end structure of the partial length fuel rod 5 is the same as the structure of the upper end plug of the conventional fuel rod, so there are no manufacturing problems.
Another advantage is that the manufacturing cost is low.
第９図に本発明のさらに他の実施例を示す０本実施例で
は、部分長燃料棒５を支持する丸セル１２を、燃料棒１
を支持する丸セル１３よりも下方に延長しかつ丸セル１
２の側面に六８を設けている０部分長燃料棒５の上端部
を支持するスペーサ６は、前述のように丸セル１２及び
１３を有している０部分長燃料棒５の上端は、スペーサ
６の丸セル１３の下端よりも下方に位置しており、丸セ
ル１２内に挿入されている。下方に延長した丸セル１２
で部分長燃料棒５の上端部を支持している。係る構造に
すると、前記実施例同様、スペーサ内の流路面積を増大
できるので、圧力損失が低下し、安定性余裕を増大でき
る。また５本変形例では、スペーサの構造のみ変更し、
部分長燃料棒については変更しないので、信頼性も高く
かつ、製造コストも安いというメリットもある。FIG. 9 shows still another embodiment of the present invention. In this embodiment, a round cell 12 supporting a part-length fuel rod 5 is connected to a fuel rod 1.
The round cell 1 extends downward from the round cell 13 that supports the round cell 1.
The spacer 6 supporting the upper end of the 0-part length fuel rod 5 is provided with 68 on the side of 2, and the upper end of the 0-part length fuel rod 5 has round cells 12 and 13 as described above. It is located below the lower end of the round cell 13 of the spacer 6 and inserted into the round cell 12. Round cell 12 extended downward
supports the upper end of the partial length fuel rod 5. With such a structure, the area of the flow path within the spacer can be increased as in the previous embodiment, so pressure loss can be reduced and stability margin can be increased. In addition, in the 5-piece modification, only the structure of the spacer is changed,
Since the partial length fuel rods are not changed, there are advantages of high reliability and low manufacturing costs.
本発明によれば、燃料集合体上部の二相流圧力損失を大
幅に低減できるので、炉心の安定性を大幅に向上させる
ことが効果がある。また、圧力損失の低減はそれ自体、
ポンプ動力の低減、定格流量増大による運転の自由度を
拡大等の効果がある。According to the present invention, the two-phase flow pressure loss in the upper part of the fuel assembly can be significantly reduced, so that it is effective to significantly improve the stability of the reactor core. In addition, the reduction in pressure loss itself
It has the effect of reducing pump power and increasing the degree of freedom of operation by increasing the rated flow rate.
第１図は本発明の一実施例を示す図、第２図は従来の燃
料集合体の構造を示す図、第３図は部分長燃料棒を装荷
した燃料集合体を示す図、第４図はスペーサの圧力損失
の低減割合と減幅比との関係を示す特性図、第５図は本
発明の概念を使用した燃料集合体の構造を示す図、第６
図は軸方向に配置された各スペーサの圧力損失の分担割
合を示す図、第７図、第８図及び第９図は本発明の他の
実施例の構成図である。
１・・・燃料棒、２・・・水ロッド、３・・・スペーサ
、４・・・チャンネルボックス、５・・・部分長燃料棒
、６・・・支持スペーサ、７・・・上端面、８・・・穴
、９・・・円筒管、１０・・・内蓋、１１・・・スプリ
ング、１２．１３・・・丸セル。Fig. 1 shows an embodiment of the present invention, Fig. 2 shows the structure of a conventional fuel assembly, Fig. 3 shows a fuel assembly loaded with partial length fuel rods, and Fig. 4. 5 is a characteristic diagram showing the relationship between the reduction rate of pressure loss of the spacer and the width reduction ratio, FIG. 5 is a diagram showing the structure of a fuel assembly using the concept of the present invention, and FIG.
The figure shows the proportion of pressure loss shared by each spacer arranged in the axial direction, and FIGS. 7, 8, and 9 are configuration diagrams of other embodiments of the present invention. DESCRIPTION OF SYMBOLS 1... Fuel rod, 2... Water rod, 3... Spacer, 4... Channel box, 5... Partial length fuel rod, 6... Support spacer, 7... Upper end surface, 8... Hole, 9... Cylindrical tube, 10... Inner lid, 11... Spring, 12.13... Round cell.
Claims (1)
料棒を有する燃料集合体において、前記第２燃料棒の上
端部に、この上部端栓より上方に向つて伸びしかも側面
に開口を有する円筒管を取付け、前記円筒管をスペーサ
で支持することを特徴とする燃料集合体。 ２、第１燃料棒及びこの第１燃料棒よりも短かい第２燃
料棒を有する燃料集合体において、前記第２燃料棒の上
端部に、前記第２燃料棒より外径の小さい棒部材を取付
け、かつ、前記棒部材をスペーサで支持することを特徴
とする燃料集合体。 ３、第１燃料棒及びこの第１燃料棒よりも短かい第２よ
り短尺となる部分長燃料棒を有し、かつ、前記第１及び
第２燃料棒をスペーサで支持する燃料集合体において、
前記第２燃料棒の上端を前記スペーサよりも下方に位置
させ、前記第２燃料棒の上端部を支持する前記スペーサ
は前記第１燃料棒を支持する第１筒状体と前記第１筒状
体よりも下方に延びて側面に開口を有ししかも前記第２
燃料棒を支持する第２筒状体とを有し、前記第２燃料棒
の上端は前記第１筒状体の下端よりも下方に位置してい
ることを特徴とする燃料集合体。[Scope of Claims] 1. In a fuel assembly having a first fuel rod and a second fuel rod shorter than the first fuel rod, a fuel rod is provided at the upper end of the second fuel rod, above the upper end plug. 1. A fuel assembly characterized in that a cylindrical tube extending toward the direction and having an opening on the side is attached, and the cylindrical tube is supported by a spacer. 2. In a fuel assembly having a first fuel rod and a second fuel rod shorter than the first fuel rod, a rod member having an outer diameter smaller than the second fuel rod is provided at the upper end of the second fuel rod. A fuel assembly characterized in that the rod member is attached and supported by a spacer. 3. A fuel assembly having a first fuel rod and a second partial length fuel rod shorter than the first fuel rod, and supporting the first and second fuel rods with a spacer,
The upper end of the second fuel rod is located below the spacer, and the spacer that supports the upper end of the second fuel rod is connected to the first cylindrical body that supports the first fuel rod and the first cylindrical body. The second
a second cylindrical body supporting fuel rods, the upper end of the second fuel rod being located below the lower end of the first cylindrical body.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63095576A JPH01269086A (en) | 1988-04-20 | 1988-04-20 | fuel assembly |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63095576A JPH01269086A (en) | 1988-04-20 | 1988-04-20 | fuel assembly |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH01269086A true JPH01269086A (en) | 1989-10-26 |
Family
ID=14141416
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP63095576A Pending JPH01269086A (en) | 1988-04-20 | 1988-04-20 | fuel assembly |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH01269086A (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5345485A (en) * | 1992-03-13 | 1994-09-06 | Siemens Power Corporation | Coolant vent fuel rod for a light water reactor |
| EP0605816A3 (en) * | 1992-12-17 | 1994-11-17 | Siemens Power Corp | Nuclear fuel assembly. |
| EP0800181A3 (en) * | 1996-04-01 | 1998-04-22 | General Electric Company | Fuel bundle for a nuclear reactor |
| US5875224A (en) * | 1997-09-02 | 1999-02-23 | General Electric Company | Swirler attachment for a spacer of a nuclear fuel bundle |
-
1988
- 1988-04-20 JP JP63095576A patent/JPH01269086A/en active Pending
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5345485A (en) * | 1992-03-13 | 1994-09-06 | Siemens Power Corporation | Coolant vent fuel rod for a light water reactor |
| US5375153A (en) * | 1992-03-13 | 1994-12-20 | Siemens Power Corporation | Coolant vent fuel rod and part length fuel rod having a reflex upper end fitting for a light water reactor |
| US5384815A (en) * | 1992-03-13 | 1995-01-24 | Siemens Power Corporation | Hydraulic resistance strip for a light water reactor |
| EP0605816A3 (en) * | 1992-12-17 | 1994-11-17 | Siemens Power Corp | Nuclear fuel assembly. |
| EP0800181A3 (en) * | 1996-04-01 | 1998-04-22 | General Electric Company | Fuel bundle for a nuclear reactor |
| US5875224A (en) * | 1997-09-02 | 1999-02-23 | General Electric Company | Swirler attachment for a spacer of a nuclear fuel bundle |
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| JPH0816711B2 (en) | Fuel assembly | |
| JPH063471A (en) | Fuel assembly | |
| JPS5872096A (en) | Segment type fuel rod | |
| JPS636491A (en) | nuclear reactor fuel assembly | |
| JPH0328794A (en) | Boiling water reactor fuel assembly and its cooling water distribution pipes | |
| JPS60238784A (en) | Fuel aggregate | |
| JPS6318291A (en) | fuel assembly | |
| JPS6264979A (en) | Fuel rod for nuclear reactor | |
| JPH0376875B2 (en) | ||
| JPS6157882A (en) | Nuclear fuel aggregate |