JP2505539B2 - Weir noise prevention device - Google Patents
Weir noise prevention deviceInfo
- Publication number
- JP2505539B2 JP2505539B2 JP63154949A JP15494988A JP2505539B2 JP 2505539 B2 JP2505539 B2 JP 2505539B2 JP 63154949 A JP63154949 A JP 63154949A JP 15494988 A JP15494988 A JP 15494988A JP 2505539 B2 JP2505539 B2 JP 2505539B2
- Authority
- JP
- Japan
- Prior art keywords
- overflow
- water film
- plate
- pressure
- gate
- 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
Description
【発明の詳細な説明】 （産業上の利用分野） 本発明は、一般河川、農業用水路等に設置される越流
型ゲートにおける堰鳴音防止装置に関するものである。TECHNICAL FIELD The present invention relates to a damming noise prevention device for an overflow gate installed in a general river, an agricultural waterway, or the like.
（従来の技術） 前記越流型ゲートの従来例を第６図ないし第９図によ
って説明すると、第６図のようにゲート（１）の上部に
越流面（1a）を下流側へ突設した構造になっており、越
流水（ａ）が越流面（1a）を越えて流出端（1b）から水
膜（a1）となり下流側水面（a2）まで落下し、ゲートと
水膜（a1）で越流面（1a）の下側に下方空洞部（３）が
形成され、下方空洞部（３）内の音響固有周波数で同空
洞部内に圧力変動が生じ易く、第７図に示すように該圧
力変動により水膜（a1）方向は（＋）圧力時に実線方
向、（−）圧力時に点線方向に変化しながら下流側水面
（a2）に達して、水膜（a1）の前記変動により下方空洞
部（３）の容積が変化し、該容積変化により下方空洞部
（３）に圧力変動が生じ該現象の繰返しにより鳴音が発
生する。(Prior Art) A conventional example of the overflow gate will be described with reference to FIGS. 6 to 9. As shown in FIG. 6, an overflow surface (1a) is provided on the upper portion of the gate (1) so as to project downstream. was has a structure, falling from KoshiRyusui (a) is overflow surface (1a) to beyond the outflow end (1b) until the aqueous layer (a 1) next downstream water surface (a 2), the gate and the water film The lower cavity (3) is formed below the overflow surface (1a) at (a 1 ), and the acoustic natural frequency in the lower cavity (3) easily causes pressure fluctuations in the cavity. As shown in Fig. 3, the water film (a 1 ) direction changes to a solid line direction at (+) pressure and a dotted line direction at (-) pressure to reach the downstream water surface (a 2 ) due to the pressure fluctuation, and the water film (a 1 ) 1) said lower cavity the volume of (3) varies with variations in, be generated is ringing by repetition of the phenomenon occurs pressure fluctuations in the lower cavity (3) by said container product change .
従来の堰鳴音防止装置は、第８図のように越流面（1
a）の流出端（1b）上にゲート幅方向の適宜間隔をおき
複数のスポイラー（５）を斜設し、各スポイラー（５）
によって水膜（a1），（a1′）に分断して、低周波数の
鳴音を発生し難くし、または、第９図のように流出端
（1b）に複数のスポイラー（６）を延設して、各スポイ
ラー（６）により水膜（a1）を乱して凹凸水流（a1″）
（a1）とし、低周波数の鳴音を発生し難くしている。As shown in Fig. 8, the conventional weir noise prevention device has
A plurality of spoilers (5) are installed on the outflow end (1b) of (a) at appropriate intervals in the gate width direction, and each spoiler (5) is installed.
It divides into water film (a 1 ) and (a 1 ′) to make low-frequency noise less likely to occur, or multiple spoilers (6) are attached to the outflow end (1b) as shown in FIG. Extending and disturbing the water film (a 1 ) by each spoiler (6), uneven water flow (a 1 ″)
(A 1 ) makes it difficult to generate low-frequency sound.
（発明が解決しようとする課題） 従来の前記堰鳴音防止装置において、前記両スポイラ
ーは、前記鳴音の発生要因に沿って開発されたものでは
なく経験的に採用されているものであって、各種ゲー
ト、各種の越流条件など全ての条件に対して有効なもの
ではない。即ち、第８図の従来例は、水膜を分断し空洞
内の固有周波数を変えようとするものであって、このた
めには分断幅を大きくする必要があり、ゲートの有効幅
が減少してゲートの流量特性が劣化し、また、ゴミ等が
溜まる問題点がある。(Problems to be Solved by the Invention) In the conventional dam noise prevention device, the both spoilers are not developed in accordance with the cause of the noise and are employed empirically. However, it is not effective for all conditions such as various gates and various overflow conditions. That is, in the conventional example shown in FIG. 8, the water film is divided to change the natural frequency in the cavity. For this purpose, it is necessary to increase the division width, which reduces the effective width of the gate. Therefore, there is a problem that the flow rate characteristic of the gate is deteriorated and dust is accumulated.
第９図の従来例は、水膜面を凹凸にすることにより空
洞内に規則的な容積変化が生じるのを防ぐものである
が、全ての流量（越流量）に対して有効とはならず、あ
る特定の流量で鳴音が発生するなどの問題点がある。The conventional example of FIG. 9 prevents irregular volume change in the cavity by making the water film surface uneven, but it is not effective for all flow rates (overflow rate). However, there is a problem that a sound is generated at a certain flow rate.
本発明は、前記のような課題に対処するために開発さ
れたものであって、その目的とする処は、越流面の流出
端を含む下流側部分を下方空洞部の圧力変動に対応させ
て凹凸変形させることにより、水膜流出方向の変化を相
殺して減少し鳴音発生の主要因をなくして、汎用性とと
もに鳴音防止性能、信頼性を向上した堰鳴音防止性能を
提供するにある。The present invention was developed in order to address the above-mentioned problems, and the object of the present invention is to make the downstream side portion including the outflow end of the overflow surface correspond to the pressure fluctuation of the lower cavity. By providing uneven deformation, the change in the water film outflow direction is offset and reduced, eliminating the main cause of noise generation, providing versatility, noise prevention performance, and dam noise prevention performance with improved reliability. It is in.
（課題を解決するための手段） 本発明は、上部に越流面を設けた越流型ゲートにおい
て、該越流面の流出端を含む下流側部分を、ゲートと水
膜によって形成される下方空洞部の圧力変動に対応して
凹凸変形する可撓性材製プレートによって構成した構成
に特徴を有し、下方空洞部の圧力変動による水膜方向の
内外への直接的な変化を、前記圧力変動に対応した可撓
性材製プレートの自動凹凸変形によって生じる水膜方向
の内外への逆方向変化により相殺している。(Means for Solving the Problem) In the present invention, in an overflow type gate having an overflow surface at an upper portion, a downstream side portion including an outflow end of the overflow surface is formed by a gate and a water film. The structure is characterized by a flexible material plate that deforms unevenly in response to pressure fluctuations in the cavity, and direct pressure changes in the water film direction due to pressure fluctuations in the lower cavity This is offset by the inward and outward reverse changes in the direction of the water film caused by the automatic uneven deformation of the flexible plate corresponding to the fluctuation.
（作用） ゲートと越流面の流出端から形成される水膜により形
成された下方空洞部の圧力変動によって、水膜方向が内
外へ直接的に変化されるのに対し、前記圧力変動に対応
して可撓性材製プレートが自動的に凹凸変形し、該凹凸
変形によって生じる内外への水膜方向の変化が逆方向と
なって、水膜方向の前記直接的な変化と前記逆方向変化
が相殺され、鳴音発生の主因となる水膜の変動が著しく
低減されて鳴音が効果的に防止されるとともに、越流水
の越流量、越流面の形状、ゲート幅等が変化しても、こ
れらのパラメータに前記直接的な変化および前記逆方向
の変化がともに追従して、基本的に同様な相殺作用が得
られ、汎用製、信頼製が得られる。(Function) The pressure fluctuation of the lower cavity formed by the water film formed from the gate and the outflow end of the overflow surface changes the direction of the water film directly in and out, but it corresponds to the pressure fluctuation. As a result, the flexible material plate automatically deforms unevenly, and the change in the direction of the water film inward and outward caused by the uneven deformation becomes the opposite direction, and the direct change and the reverse direction change of the water film direction. Is canceled out, and the fluctuation of the water film, which is the main cause of the sound generation, is significantly reduced and the sound is effectively prevented, and the overflow volume of the overflow water, the shape of the overflow surface, the gate width, etc. are changed. Also, the direct change and the reverse change both follow these parameters, and basically the same canceling action is obtained, and a general-purpose product and a reliable product are obtained.
（実施例） 第１図ないし第３図に本発明の第１実施例を示し、図
中（10）はゲート、（10a）はゲート（10）上部に設け
られ下流側に突設された越流面、（13）はゲートと水膜
（a1）によって形成される下方空洞部であって、上部に
越流面（10a）を設けた越流型ゲートにおいて、越流面
（10a）の流出端（10b）を含む下流側部分を、下方空洞
部（13）の圧力変動に対応して凹凸変形する可撓性材製
プレート（15）によって構成した堰鳴音防止装置になっ
ている。(Embodiment) A first embodiment of the present invention is shown in FIGS. 1 to 3, in which (10) is a gate, and (10a) is an upper portion of the gate (10) and is provided on the downstream side so as to project. The flow surface, (13) is a lower cavity formed by the gate and the water film (a 1 ). In the overflow gate with the overflow surface (10a) at the upper part, This is a damming noise prevention device in which a downstream side portion including the outflow end (10b) is constituted by a flexible plate (15) which is unevenly deformed according to the pressure fluctuation of the lower cavity (13).
前記越流面（10a）は、鉄材などで構成され、該越流
面（10a）における流出端（10b）を含む下流側部分は、
可撓性材製プレート（15）で構成されており、該可撓性
材製プレート（15）は、ゴムなどの可撓性材からなり、
第３図に示すように越流面（10a）と流出端（10b）に加
硫接着などで接着され、可撓性材製プレート（15）の下
部には開放部（16）が形成されて、下方空洞部（13）内
の圧力がプラス圧になると、第２図のように可撓性材製
プレート（15）が外側へ凸変形されて実線で示すように
なり、逆にマイナス圧になると、内側へ凹変形されて点
線で示すように凹凸変形される。The overflow surface (10a) is made of an iron material or the like, and the downstream portion of the overflow surface (10a) including the outflow end (10b) is
The flexible plate (15) is made of a flexible material such as rubber.
As shown in FIG. 3, the overflow surface (10a) and the outflow end (10b) are adhered by vulcanization or the like, and the open part (16) is formed in the lower part of the flexible plate (15). When the pressure in the lower cavity (13) becomes a positive pressure, the plate (15) made of a flexible material is convexly deformed outward as shown in FIG. 2 and shown by a solid line. Then, it is concavely deformed inward and is irregularly deformed as shown by a dotted line.
本発明は、前記のような構成になっており作用につい
て詳述すると、第１図に示すように越流水（ａ）が越流
面（10a）、可撓性材製プレート（15）を越えて流出端
（10b）から水膜（a1）となり下流側水面（a2）まで落
下すると、ゲートと水膜（a1）により越流面（10a）の
下側に下方空洞部（13）が形成される。The present invention is configured as described above, and the operation will be described in detail. As shown in FIG. 1, the overflow water (a) exceeds the overflow surface (10a) and the flexible plate (15). When it becomes a water film (a 1 ) from the outflow end (10b) and falls to the downstream water surface (a 2 ), the lower cavity (13) is located below the overflow surface (10a) due to the gate and the water film (a 1 ). Is formed.
該下方空洞部（13）内に圧力変動が生じ、第７図に示
すように下方空洞部（13）内の圧力が変動してプラス圧
になると、水膜（a1）が実線で示すように外方へ変化さ
れ、マイナス圧になると点線で示すように内側へ変化さ
れるが、本発明では、第２図に示すように下方空洞部
（13）内の圧力がプラス圧になると、プラス圧によって
可撓性材製プレート（15）が実線で示すように外側へ凸
変形され、該凸変形による流出端（10b）部分のガイド
面傾斜が増加し、水膜が第７図の場合とは逆に内側へ変
化され、下方空洞部（13）内の圧力がマイナス圧になる
と、マイナス圧によって可撓性材製プレート（15）が点
線に示すように内側へ凹変形され、該凹変形による流出
端（10b）部分のガイド面傾斜が減少し、水膜が第７図
の場合とは逆に外側へ変動されて、第７図に示した水膜
（a1）の方向の直接的な変化が、可撓性材製プレート
（15）による水膜（a1）方向の逆方向の変化によって相
殺され、水膜（a1）の変動が著しく低減され、鳴音発生
の主因となる水膜の変動が殆んどなくなって、鳴音発生
が効果的に防止される。When a pressure fluctuation occurs in the lower cavity (13) and the pressure in the lower cavity (13) fluctuates to a positive pressure as shown in FIG. 7, the water film (a 1 ) is shown by a solid line. When the pressure in the lower cavity (13) becomes positive as shown in FIG. 2, it becomes positive when the pressure in the lower cavity (13) becomes positive as shown in FIG. The flexible plate (15) is convexly deformed outward by the pressure as shown by the solid line, the guide surface inclination of the outflow end (10b) is increased by the convex deformation, and the water film is different from that in FIG. On the contrary, when the pressure in the lower cavity (13) becomes a negative pressure, the negative pressure causes the flexible plate (15) to be concavely deformed inward as shown by the dotted line, and the concave deformation The inclination of the guide surface at the outflow end (10b) due to is reduced and the water film is moved outward, contrary to the case of Fig. 7. Then, the direct change in the direction of the water film (a 1 ) shown in FIG. 7 is offset by the change in the opposite direction of the water film (a 1 ) direction due to the plate (15) made of a flexible material. The fluctuation of the membrane (a 1 ) is remarkably reduced, the fluctuation of the water film, which is the main cause of the sound generation, is almost eliminated, and the sound generation is effectively prevented.
越流水（ａ）越流量、越流面（10a）の形状、ゲート
幅等が変っても、基本的には前記水膜の前記変動減少の
メカニズムは不変である。即ち、前記パラメータの越流
量は鳴音、即ち下方空洞部（13）の圧力変動の周波数を
変えるが、可撓性材製プレート（15）の作用効果は周波
数変化の影響は受けない。換言すれば、可撓性材製プレ
ートの作用効果は周波数の変化に追従するものである。Even if the overflow water (a) overflow, the shape of the overflow surface (10a), the gate width, etc. change, the mechanism of the fluctuation reduction of the water film is basically unchanged. That is, the overflow of the above parameter changes the sound, that is, the frequency of the pressure fluctuation of the lower cavity (13), but the effect of the flexible plate (15) is not affected by the frequency change. In other words, the effect of the flexible plate follows the change in frequency.
また、可撓性材製プレート（15）の代表的なものとし
てはゴムであるが、ゴムの比重は1.1〜1.2程度で水の比
重にほぼ等しく、該可撓性材製プレートは越流水（ａ）
を含めて下方空洞部（13）内の圧力変動に対し十分な応
答性を有し、前記作用と相まって汎用性、信頼性を有し
ている。Further, a typical example of the flexible material plate (15) is rubber, but the specific gravity of the rubber is about 1.1 to 1.2, which is almost equal to the specific gravity of water. a)
It has sufficient responsiveness to pressure fluctuations in the lower cavity portion (13) including the above, and has versatility and reliability in combination with the above-mentioned action.
また、可撓性材製プレート（15）に加わる圧力は、下
部空洞（13）内の圧力変動と同相であることが必要であ
り、このためには、越流面（10a）直下の空間部（13a）
の共鳴周波数が、下方空洞部（13）内の圧力変動の周波
数に比べ大であることが必要であって、このため、開放
部（16）の面積は、次の関係を満足するように設定す
る。Further, the pressure applied to the flexible plate (15) needs to be in the same phase as the pressure fluctuation in the lower cavity (13), and for this purpose, the space directly below the overflow surface (10a). (13a)
The resonance frequency of the open cavity (16) must be higher than the frequency of the pressure fluctuation in the lower cavity (13). Therefore, the area of the open section (16) must be set to satisfy the following relationship. To do.
S :開放部（16）の面積（m2） h :開放部（16）の厚さ（ｍ） v :空間部（13a）の容積（m3） c :空気中の音速（m/s） f0:下方空洞部（13）の圧力変動（鳴音）の周波数（H
z） （他の実施例） 第４図に可撓性材製プレートの他の実施例を示し、第
３図に示す第１実施例に比べると、可撓性材製プレート
（15a）の上流側端部を越流面（10a）の端部下側に加硫
接着などにより接着して、下流側端部を流出端（10b）
の外側に同様な手段で接着した構成に特徴を有し、その
他の構成は第１実施例と基本的に同様な構成になってい
る。 S: Area of open part (16) (m 2 ) h: Thickness of open part (16) (m) v: Volume of space part (13a) (m 3 ) c: Sound velocity in air (m / s) f 0 : Frequency of pressure fluctuation (sound) in the lower cavity (13) (H
z) (Other Embodiments) FIG. 4 shows another embodiment of the plate made of flexible material, which is upstream of the plate (15a) made of flexible material as compared with the first embodiment shown in FIG. The side end is bonded to the lower side of the overflow surface (10a) by vulcanization, and the downstream end is connected to the outflow end (10b).
The structure is characterized in that it is adhered to the outside by a similar means, and other structures are basically the same as those of the first embodiment.
第５図に可撓性材製プレート他の実施例を示してお
り、第４図の実施例の接着に代えて座金（20）とボルト
（またはビス）（21）で取付けた可撓性材製プレート
（15b）の構成に特徴を有し、その他の構成は第１実施
例と基本的に同様になっており、第４図および第５図に
示す実施例においても第１実施例と同様な作用効果が得
られる。FIG. 5 shows another embodiment of a plate made of a flexible material, and a flexible material which is attached with a washer (20) and a bolt (or screw) (21) instead of the adhesive of the embodiment of FIG. The plate-making plate (15b) is characterized in that the other structure is basically the same as that of the first embodiment. The embodiment shown in FIGS. 4 and 5 is also the same as that of the first embodiment. Various operational effects can be obtained.
（発明の効果） 本発明は、前述のような構成になっており、ゲートと
流出する水膜で形成される下方空洞部の圧力変動による
水膜方向の内外への直接的な変化は、前記圧力変動に対
応した可撓性材製プレートの自動凹凸変形によって生じ
る水膜方向の逆方向変化によって相殺され、鳴音発生の
主因となる水膜方向の変動が効果的に低減されるととも
に、前記両変化は、基本的に越流水の越流量、越流面の
形状、ゲート幅等に対応し追従し、相殺による水膜変動
の低減効果は同様に得られ、汎用性とともに鳴音防止性
能、信頼性が著しく向上されている。(Effects of the Invention) The present invention has the above-mentioned configuration, and the direct change inward and outward in the direction of the water film due to the pressure fluctuation of the lower cavity formed by the gate and the water film flowing out is The fluctuation in the water film direction, which is the main cause of the sound generation, is effectively reduced and offset by the reverse change in the water film direction caused by the automatic uneven deformation of the flexible material plate corresponding to the pressure fluctuation, and Both changes basically follow the overflow of the overflow water, the shape of the overflow surface, the gate width, etc., and the effect of reducing the fluctuation of the water film due to the cancellation can be obtained in the same manner. Reliability is significantly improved.
以上本発明を実施例について説明したが、勿論本発明
はこのような実施例にだけ局限されるものではなく、本
発明の精神を逸脱しない範囲内で種々の設計の改変を施
しうるものである。Although the present invention has been described with reference to the embodiments, the present invention is of course not limited to such embodiments, and various design modifications can be made without departing from the spirit of the present invention. .
第１図（Ａ）は本発明の第１実施例を示す全体の側視
図、第１図（Ｂ）は第１図（Ａ）のＩ部分の拡大断面
図、第２図は可撓性材製プレートの作用を示す断面図、
第３図は可撓性材製プレートの第１実施例を示す要部断
面図、第４図は可撓性材製プレートの他の実施例を示す
要部断面図、第５図は同じく他の実施例を示す要部断面
図、第６図は従来例を示す側視図、第７図は第６図の要
部断面図、第８、９図は従来の鳴音防止装置の各斜視図
である。 10:ゲート、10a:越流面 10b:流出端 15,15a,15b:可撓性材製プレートFIG. 1 (A) is an overall side view showing the first embodiment of the present invention, FIG. 1 (B) is an enlarged sectional view of a portion I in FIG. 1 (A), and FIG. Sectional view showing the action of the material plate,
FIG. 3 is a sectional view showing the first embodiment of the plate made of a flexible material, FIG. 4 is a sectional view showing the main portion of another embodiment of the plate made of a flexible material, and FIG. FIG. 6 is a side view showing a conventional example, FIG. 7 is a cross-sectional view of the principal part of FIG. 6, and FIGS. 8 and 9 are perspective views of a conventional noise suppression device. It is a figure. 10: Gate, 10a: Overflow surface 10b: Outflow end 15,15a, 15b: Plate made of flexible material
Claims (1)
て、越流面の下流側部分を可撓性材製プレートで構成
し、該プレートの上流側端と下流側端を固定してその中
間部が凹凸変形自在とするとともに、該プレート下面が
ゲート構造物と越流面から流下することによってできる
水の膜とによって形成される空洞部に面するように配設
し、該空洞部の圧力変化によって前記プレートが凹凸変
形可能にしたことを特徴とする堰鳴音防止装置。1. In an overflow gate having an overflow surface at an upper portion thereof, a downstream side portion of the overflow surface is constituted by a plate made of a flexible material, and an upstream end and a downstream end of the plate are fixed. The hollow portion of the plate is arranged so that it can be deformed unevenly, and the lower surface of the plate faces a hollow portion formed by the gate structure and a water film formed by flowing down from the overflow surface. A damming noise prevention device, characterized in that the plate can be deformed in a concavo-convex manner by a change in pressure of a portion.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63154949A JP2505539B2 (en) | 1988-06-24 | 1988-06-24 | Weir noise prevention device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63154949A JP2505539B2 (en) | 1988-06-24 | 1988-06-24 | Weir noise prevention device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH01322017A JPH01322017A (en) | 1989-12-27 |
| JP2505539B2 true JP2505539B2 (en) | 1996-06-12 |
Family
ID=15595439
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP63154949A Expired - Lifetime JP2505539B2 (en) | 1988-06-24 | 1988-06-24 | Weir noise prevention device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2505539B2 (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115233631B (en) * | 2022-06-06 | 2023-10-24 | 华北水利水电大学 | Abnormal sound eliminating device for inverted siphon outlet |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5290136A (en) * | 1976-01-23 | 1977-07-28 | Nippon Kokan Kk | Structure of floodgate |
| JPS5673734U (en) * | 1979-11-05 | 1981-06-17 |
-
1988
- 1988-06-24 JP JP63154949A patent/JP2505539B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPH01322017A (en) | 1989-12-27 |
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