JPS5946520A - Method and apparatus for measuring underwater acoustic power generated by ship - Google Patents
Method and apparatus for measuring underwater acoustic power generated by shipInfo
- Publication number
- JPS5946520A JPS5946520A JP57157330A JP15733082A JPS5946520A JP S5946520 A JPS5946520 A JP S5946520A JP 57157330 A JP57157330 A JP 57157330A JP 15733082 A JP15733082 A JP 15733082A JP S5946520 A JPS5946520 A JP S5946520A
- Authority
- JP
- Japan
- Prior art keywords
- sensor
- ship
- acoustic power
- measured
- hydrophone
- 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
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01H—MEASUREMENT OF MECHANICAL VIBRATIONS OR ULTRASONIC, SONIC OR INFRASONIC WAVES
- G01H3/00—Measuring characteristics of vibrations by using a detector in a fluid
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Measurement Of Mechanical Vibrations Or Ultrasonic Waves (AREA)
- Measurement Of Velocity Or Position Using Acoustic Or Ultrasonic Waves (AREA)
Abstract
Description
【発明の詳細な説明】
本発明は船舶の水中放射音響パワーを正確に測定するた
めの改良された方法及び装置に関する。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improved method and apparatus for accurately measuring the underwater radiated acoustic power of a ship.
船舶航行時において船体が水中に放射する騒音を低下さ
せることが次第に要求される様になり、その対策を施す
ためには船舶の水中放射音響パワーを正確に測定するこ
とが必要である。このために従来は通常の水中マイクロ
ホンを用いて何個所かにおいて音響測定を行いこれを電
気的出力として記録し、そのデータから船舶の放射する
全音響パワーを推測していた。しかしながら、この様な
方法では全音響パワーを正確に測定することはできず、
かなりの誤差を伴う。It is increasingly required to reduce the noise emitted by the ship's body into the water during navigation, and in order to take countermeasures, it is necessary to accurately measure the underwater radiated sound power of the ship. To this end, conventional underwater microphones have been used to make acoustic measurements at several locations, record this as an electrical output, and use this data to estimate the total acoustic power radiated by the ship. However, this method cannot accurately measure the total acoustic power;
It involves a considerable amount of error.
本発明は、以上の如き現状に鑑み、船舶の放射する水中
音響パワーを極めて正確に測定することを目的とするも
のである。In view of the current situation as described above, the present invention aims to extremely accurately measure underwater acoustic power radiated by a ship.
本発明の１つは測定方法に関するものであり、弾性光学
的効果により音響パワーを測定し得る光フアイバーハイ
ドロホンの線状センサーを、被測定船舶に対する相対的
位置関係において軌跡が水面下で閉じた面を形成し該閉
じた面によシ切り出される水域に上記被測定船舶が存在
する如くに掃引し、且つ上記閉じた面に関して上記ハイ
ドロホンの出力を積分することを特徴とする。One of the present inventions relates to a measurement method, in which a linear sensor of an optical fiber hydrophone capable of measuring acoustic power by an elasto-optic effect is closed under the water surface in terms of its relative position to the vessel to be measured. The method is characterized in that a surface is formed, and the water area cut out by the closed surface is swept so that the vessel to be measured is present therein, and the output of the hydrophone is integrated with respect to the closed surface.
水中における音響パワーの検出のために光ファイバーを
利用することについてはたとえば特開昭５６−９８６２
２号公報に記載がある。即ち、液体中における光ファイ
バーは音響圧力を受けるとその大きさに応じて長さ及び
屈折率に変化を生じ、該ファイバー中を通過するレーザ
ー光は位相に変化を生ずる。この様な弾性光学的効果を
有する光ファイバーをセンサーとして用い、該センサー
を通過する前のレーザー光の一部を参照光として分離し
、これをセンサー通過後のレーザー光と重ね合わせるこ
とにより音響パワーを干渉計測的に検出し電気信号とし
て取り出すハイドロホンが特開昭５６−１２５１８号公
報に記載されている。Regarding the use of optical fibers for detecting acoustic power underwater, for example, Japanese Patent Application Laid-Open No. 56-9862
There is a description in Publication No. 2. That is, when an optical fiber in a liquid is subjected to acoustic pressure, its length and refractive index change depending on the magnitude of the acoustic pressure, and the phase of a laser beam passing through the fiber changes. An optical fiber with such an elastic optical effect is used as a sensor, and a part of the laser light before passing through the sensor is separated as a reference light, and this is superimposed with the laser light after passing through the sensor to increase the acoustic power. A hydrophone that is detected interferometrically and extracted as an electrical signal is described in Japanese Patent Laid-Open No. 12518/1983.
上記本発明方法はこの様な弾性光学的効果を利用した光
フアイバーハイドロホンを用いるものである。本発明方
法の原理を第１図に示す。即ち、光フアイバーハイドロ
ホンのセンサー１として線状に形成したものを用いて、
その水面下における軌跡が閉じた面Ａを形成する様に掃
引する。ここで、閉じた面とは、該面によりその内部の
水域と外部の水域とが完全に区別し得る様なものである
。センサー１の掃引は、切り出された水域に被測定船舶
Ｂが存在する様に行う。同、以上のセンサー１の掃引は
被測定船舶Ｂとの相対的位置関係に関して行われればよ
いのであって、たとえば船舶Ｂが航行している場合にお
いてはセンサー１は単に上下運動するだけでもよい。ハ
イドロホンの出力は線状センサー１の存在する線上の音
響パワーによるものであるので、この出力を上記の如く
にして切り出した閉じた面Ａ全体にわたって積分するこ
とにより被測定船舶Ｂが水中に放射する音響パワーを正
確に測定できるのである。伺、この方法においてはセン
サー１の掃引に時間を要しまた船体からセンサー塩の距
離も変化するので厳密には特定時刻において船舶Ｂが水
中に放射する音響パワーを測定していることにはならな
いが、船舶Ｂの出力を一定に保っておけば音響パワーを
正確に測定したことになる。The method of the present invention described above uses an optical fiber hydrophone that utilizes such elastic optical effects. The principle of the method of the present invention is shown in FIG. That is, using a linearly formed sensor 1 of an optical fiber hydrophone,
The trajectory under the water surface is swept so as to form a closed surface A. Here, a closed surface is one that allows the interior water area to be completely distinguished from the exterior water area. The sensor 1 sweeps so that the vessel B to be measured is present in the cut-out water area. Similarly, the above-described sweeping of the sensor 1 may be performed with respect to the relative positional relationship with the vessel B to be measured. For example, when the vessel B is sailing, the sensor 1 may simply move up and down. Since the output of the hydrophone is based on the acoustic power on the line where the linear sensor 1 is located, by integrating this output over the entire closed surface A cut out as described above, it is possible to calculate the amount of radiation emitted by the vessel B into the water. It is possible to accurately measure the acoustic power generated by the sound. However, in this method, it takes time to sweep sensor 1, and the distance of the sensor salt from the ship's hull changes, so strictly speaking, it does not mean that we are measuring the acoustic power emitted by ship B into the water at a specific time. However, if the output of ship B is kept constant, the acoustic power will be measured accurately.
本発明の他の１つは、上記本発明方法の実施に特に好適
に用いられる測定装置に関するものであり、弾性光学的
効果により音響パワーを測定し得る光ファイパーツ１イ
ドロホンの線状センサーがＵ字形に形成されて該センサ
ーよりも大なるＵ字形の枠体の内側に両側から支持せし
められており、該枠体の両側柱には浮子が付属せしめら
れており、上記センサーは枠体に付属せしめられた駆動
手段により枠体に対し上下動可能であるか又は／及び浮
子付近の高さを軸として枠体に対し回動可能であり、一
方上記センサーに対する被測定船舶の相対的位置を検出
し得る手段が設けられており、上記ハイドロホンの出力
を上記相対的位置に関し積分し得る手段を有することを
特徴とする。Another aspect of the present invention relates to a measuring device particularly suitably used for carrying out the method of the present invention, in which a linear sensor of an optical fiber part 1 hydrophone capable of measuring acoustic power by an elastic optical effect is used. It is formed into a U-shaped frame and is supported from both sides inside a U-shaped frame that is larger than the sensor, and floats are attached to both side pillars of the frame, and the sensor is attached to the frame. It is movable up and down with respect to the frame body by means of a driving means provided and/or rotatable with respect to the frame body about a height near the float, while detecting the relative position of the vessel to be measured with respect to the above-mentioned sensor. means are provided for integrating the output of said hydrophone with respect to said relative position.
以下図面を参照しながら本発明装置の具体例を説明する
。A specific example of the apparatus of the present invention will be described below with reference to the drawings.
第２図は本発明装置の構成概略図である。FIG. 2 is a schematic diagram of the configuration of the apparatus of the present invention.
ハイドロホンのセンサー１は線状であり、中央部付近が
最も低くなる様に曲げられている（以下この様な形状を
総称してＵ字形というＬ該センサー１１はたとえば第３
図にその切断斜視図を示す如く、強化プラスチック等の
海水と音響インピーダンスの近似する棒状部材２中に光
ファイバー３を埋め込んでなる〔第３図（ａ）〕か又は
この様な棒状部材２に光ファイバ３をラセン状に巻きつ
けてなる〔第３図（ｂ）〕ものでよい。センサー１の構
造はその他適宜変（財）することができる。光ファイバ
ー３は便宜上センサー１の一方の端部から入って他方の
端部にて折返して入光側と出光側とが同一の端部にくる
様にするのが好ましいが、これに限定されるものではな
い。センサー１０両端部はＵ字形の枠体４により支持さ
れている。The sensor 1 of the hydrophone is linear and bent so that it is lowest near the center (hereinafter, such a shape will be collectively referred to as a U-shape).The sensor 11 is, for example, a third
As shown in the cutaway perspective view in the figure, the optical fiber 3 is embedded in a rod-shaped member 2 made of reinforced plastic or the like whose acoustic impedance is similar to that of seawater [Fig. 3 (a)], or the optical fiber 3 is embedded in such a rod-shaped member 2. It may be made by winding the fiber 3 in a helical shape [FIG. 3(b)]. The structure of the sensor 1 may be modified as appropriate. For convenience, it is preferable that the optical fiber 3 enters the sensor 1 from one end and is folded back at the other end so that the light input side and the light output side are at the same end, but the present invention is not limited to this. isn't it. Both ends of the sensor 10 are supported by a U-shaped frame 4.
この枠体４はたとえば金属製であり、その両側柱の上部
には浮子５，５′が取り付けられている。第２図の場合
においてはセンサー１は枠体４に付属せしめられた駆動
手段６により軸Ｘの回りに回動可能な如くに支持されて
いる。また、センサー１は第４図（ａ） （ｔ＞）に示
す如く適宜の駆動手段（図示せず）により枠体４に対し
て上下動可能な如くに支持されていてもよい。更に、セ
ンサー１は枠体４に対して上記の如き上下動及び回動を
組合わせた動きをする様に支持されていてもよい。This frame body 4 is made of metal, for example, and floats 5, 5' are attached to the upper portions of both side pillars. In the case of FIG. 2, the sensor 1 is supported so as to be rotatable about an axis X by a drive means 6 attached to a frame 4. Further, the sensor 1 may be supported so as to be movable up and down relative to the frame 4 by an appropriate driving means (not shown) as shown in FIG. 4(a) (t>). Furthermore, the sensor 1 may be supported with respect to the frame 4 so as to move in a combination of vertical movement and rotation as described above.
センサー１の端部から出た光ファイバー３には測定部Ｔ
が接続されている。該測定部７けレーザー光源８、半透
鋼９，９’及びレンズ１０．１０’、１０”等を有し、
光源８から出た光のうち一部は参照光とされ残部は光フ
ァイバー３に入りセンサー１を通過した後に光ファイバ
ー３から出て上記参照光と重ね合わせられ検出器１１へ
入る。検出器１１の出力は増幅器１２により増幅される
。The optical fiber 3 coming out from the end of the sensor 1 has a measurement part T.
is connected. The measuring section has 7 laser light sources 8, semi-transparent steel 9, 9' and lenses 10, 10', 10'', etc.
A part of the light emitted from the light source 8 is used as a reference light, and the remaining part enters the optical fiber 3, passes through the sensor 1, exits from the optical fiber 3, is superimposed on the reference light, and enters the detector 11. The output of detector 11 is amplified by amplifier 12.
一方、本発明装置には被測定船舶の位置を検出するだめ
の手段１３が設けられている。On the other hand, the device of the present invention is provided with means 13 for detecting the position of the vessel to be measured.
これはセンサー１に対する被測定船舶の相対的な位置を
知るだめのものであり、たとえば被測定船舶から発せら
れる電波を２個の離隔せる受信器１４．１４’により受
信してその位置を算出する如きものが例示できる。そし
て上記電気的に増幅された音響パワー信号と上記位置の
信号とは積分器１５に入力され、ここで音響パワー信号
は上記相対的位置に関し積分される。This is to know the relative position of the ship to be measured with respect to the sensor 1. For example, radio waves emitted from the ship to be measured are received by two separate receivers 14 and 14' and the position is calculated. An example is something like this. The electrically amplified acoustic power signal and the position signal are then input to an integrator 15, where the acoustic power signal is integrated with respect to the relative position.
第５図に本発明装置の使用方法の概略図を示す。先ず、
水面上に本装置のセンサー１及び枠体を浮かベセンサー
１は予め水面上へ上げた状態としておく。枠体は常に垂
直位置を保つ（これは図示しない）、、測定部７及び位
置検出手段１３ならびにこれらに付随する機器は陸上又
は停止船上に載置しておく。被測定船舶Ｂは上記枠体の
Ｕ字形内を通過すべく一定出力にて進行する〔第５図（
ａ） ）。次に、駆動手段によりセンサー１を回動せし
め水中にて垂直状態とする〔第５図（ｂ）〕。被測定船
舶Ｂはセンサー１のＵ字形内を通過し〔第５図（ｃ）〕
、最後に駆動手段によりセンサー１を回動せしめセンサ
ー１を水面上へ上げる〔第５図（ｄ）〕。以上の如き操
作により、センサ、−（９）
１の軌跡は第１図で示されると同様な被測定船舶に対す
る相対的位置に関する閉じた面を水中に形成することに
なる。この操作におけるハイドロホンの出力は位置検出
手段１３の位置信号に基き積分され、これにより第１図
における閉じた面Ａと同様な閉じた面に関する全音響パ
ワーが測定されたことになる。これが被測定船舶Ｂの水
中放射音響パワーで紘る。FIG. 5 shows a schematic diagram of how to use the device of the present invention. First of all,
The sensor 1 and the frame of this device are floated on the water surface.The sensor 1 is raised above the water surface in advance. The frame always maintains a vertical position (this is not shown), and the measuring section 7, position detecting means 13, and associated equipment are placed on land or on a stationary ship. The vessel B to be measured moves at a constant power in order to pass through the U-shape of the frame [Fig. 5 (
a) ). Next, the sensor 1 is rotated by the driving means to be in a vertical state in the water [FIG. 5(b)]. Vessel B to be measured passes within the U-shape of sensor 1 [Figure 5 (c)]
Finally, the driving means rotates the sensor 1 and raises the sensor 1 above the water surface (FIG. 5(d)). By the above operations, the locus of the sensor -(9)1 forms a closed surface in the water regarding the relative position with respect to the vessel to be measured, similar to that shown in FIG. The output of the hydrophone in this operation is integrated based on the position signal of the position detecting means 13, and thereby the total acoustic power for a closed surface similar to closed surface A in FIG. 1 is measured. This is caused by the underwater radiated sound power of the vessel B to be measured.
以上の如き本発明方法及び装置によれば船舶の水中放射
音響パワーを容易且つ正確に測定し得るので船舶の水中
騒音低減対策上極めて有効なデータが得られ、実用的価
値は高い。According to the method and apparatus of the present invention as described above, it is possible to easily and accurately measure the underwater radiated sound power of a ship, so that extremely effective data can be obtained for measures to reduce underwater noise of ships, and the practical value is high.
第１図は本発明方法の原理を示す概略図である。第２図
は本発明装置の構成概略図である。第ａ 図（ｔ）（ｂ
）はハイドロホンセンサーの切断斜視図である。第４図
（、） （ｂ）はノ・イドロホンセンサー及び枠体の具
体例を示す概略図である。第５図（、）〜（ｄ）は本発
明装置の使用方法の（１０）
概略図である。
Ａ：閉じた面 Ｂ：被測定船舶
１：ハイドロホンセンザ−２＝枠棒状材３：光ファイバ
ー ４二枠体
ｓ、ｓ’ ：浮子 ６ニセンサ一駆動手段７：測定
部 ８：レーザー光源
９．９’ ：半透鏡 １０，１０’、１０“：レン
ズ １１：検出器 １２：増幅器 １３：位置
検出手段
１４．１４’：受信器 １５：積分器（１１）
！ｓ １ 図
第３図
（ａ） （ｂ）FIG. 1 is a schematic diagram showing the principle of the method of the present invention. FIG. 2 is a schematic diagram of the configuration of the apparatus of the present invention. Figure a (t) (b)
) is a cutaway perspective view of the hydrophone sensor. FIG. 4(b) is a schematic diagram showing a specific example of the hydrophone sensor and frame. FIGS. 5(a) to 5(d) are (10) schematic diagrams of how to use the apparatus of the present invention. A: Closed surface B: Vessel to be measured 1: Hydrophone sensor 2 = Frame rod 3: Optical fiber 4 Two frames s, s': Float 6 Two sensors - driving means 7: Measuring unit 8: Laser light source 9. 9': Semi-transparent mirror 10, 10', 10'': Lens 11: Detector 12: Amplifier 13: Position detection means 14.14': Receiver 15: Integrator (11) !s 1 Figure 3 (a) (b)
Claims (2)
性光学的効果により音響パワーを測定し得る光フアイバ
ーハイドロホンの線状センサーを、被測定船舶に対する
相対的位置関係において軌跡が水面下で閉じた面を形成
し該閉じた面により切り出される水域に上記被測定船舶
が存在する如くに掃引し、且つ上記閉じた面に関して上
記ハイドロホンの出力を積分することを特徴とする、船
舶の水中放射音響パワーの測定方法。(1) When measuring the underwater radiated acoustic power of a ship, a fiber optic hydrophone linear sensor that can measure acoustic power using an elasto-optic effect is placed so that its trajectory is below the water surface relative to the measured ship. An underwater vessel, characterized in that it forms a closed surface and sweeps the water area cut out by the closed surface so that the vessel to be measured is present, and integrates the output of the hydrophone with respect to the closed surface. How to measure radiated acoustic power.
において、弾性光学的効果により音響パワーを測定し得
る光フアイバーハイドロホンの線状センサーがＵ字形に
形成されて該センサーよりも大なるＵ字形の枠体の内側
に両側から支持せしめられておシ、該枠体の両側柱には
浮子が付属せしめられており、上記センサーは枠体に付
属せしめられた駆動手段により枠体に対し上下動可能で
あるか又は／及び浮子付近の高さを軸として枠体に対し
回動可能であり、一方上記センサーに対する被測定船舶
の相対的位置を検出し得る手段が設けられており、上記
ハイドロホンの出力を上記相対的位置に関し積分し得る
手段を有することを特徴とする、船舶の水中放射音響パ
ワーの測定装置。(2) In a device for measuring underwater radiated acoustic power of a ship, a linear sensor of an optical fiber hydrophone capable of measuring acoustic power by an elasto-optic effect is formed in a U-shape, and the linear sensor has a U-shape larger than the sensor. The sensor is supported from both sides inside a letter-shaped frame body, and floats are attached to both side columns of the frame body, and the sensor is moved up and down relative to the frame body by a driving means attached to the frame body. Means are provided which are movable and/or rotatable with respect to the frame about a height near the float, and which are capable of detecting the relative position of the vessel to be measured with respect to the sensor; 1. An apparatus for measuring underwater radiated sound power of a ship, characterized in that it has means for integrating the output of a phone with respect to the relative position.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP57157330A JPS5946520A (en) | 1982-09-09 | 1982-09-09 | Method and apparatus for measuring underwater acoustic power generated by ship |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP57157330A JPS5946520A (en) | 1982-09-09 | 1982-09-09 | Method and apparatus for measuring underwater acoustic power generated by ship |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPS5946520A true JPS5946520A (en) | 1984-03-15 |
Family
ID=15647332
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP57157330A Pending JPS5946520A (en) | 1982-09-09 | 1982-09-09 | Method and apparatus for measuring underwater acoustic power generated by ship |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS5946520A (en) |
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| JP2010115290A (en) * | 2008-11-12 | 2010-05-27 | Shiro Okada | Male urine receiver |
| CN111189526A (en) * | 2020-01-09 | 2020-05-22 | 哈尔滨工程大学 | Device and method for measuring underwater radiation noise of ship in specific dock |
| WO2022034748A1 (en) * | 2020-08-13 | 2022-02-17 | 日本電気株式会社 | Underwater noise monitoring device, underwater noise monitoring method, and storage medium |
-
1982
- 1982-09-09 JP JP57157330A patent/JPS5946520A/en active Pending
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2009288104A (en) * | 2008-05-29 | 2009-12-10 | Ihi Corp | Underwater sound measurement apparatus of towed model ship, and method for the same |
| JP2010115290A (en) * | 2008-11-12 | 2010-05-27 | Shiro Okada | Male urine receiver |
| CN111189526A (en) * | 2020-01-09 | 2020-05-22 | 哈尔滨工程大学 | Device and method for measuring underwater radiation noise of ship in specific dock |
| WO2022034748A1 (en) * | 2020-08-13 | 2022-02-17 | 日本電気株式会社 | Underwater noise monitoring device, underwater noise monitoring method, and storage medium |
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