JPH07208540A - Vibrationproof device for cylindrical structure body - Google Patents
Vibrationproof device for cylindrical structure bodyInfo
- Publication number
- JPH07208540A JPH07208540A JP6001597A JP159794A JPH07208540A JP H07208540 A JPH07208540 A JP H07208540A JP 6001597 A JP6001597 A JP 6001597A JP 159794 A JP159794 A JP 159794A JP H07208540 A JPH07208540 A JP H07208540A
- Authority
- JP
- Japan
- Prior art keywords
- vibration
- blocking
- cylindrical structure
- wind turbine
- structure body
- 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.)
- Granted
Links
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
- F05B—INDEXING SCHEME RELATING TO WIND, SPRING, WEIGHT, INERTIA OR LIKE MOTORS, TO MACHINES OR ENGINES FOR LIQUIDS COVERED BY SUBCLASSES F03B, F03D AND F03G
- F05B2250/00—Geometry
- F05B2250/20—Geometry three-dimensional
- F05B2250/23—Geometry three-dimensional prismatic
- F05B2250/231—Geometry three-dimensional prismatic cylindrical
-
- 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
- Y02E10/00—Energy generation through renewable energy sources
- Y02E10/70—Wind energy
- Y02E10/72—Wind turbines with rotation axis in wind direction
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は、マリンタワー、風車タ
ワー、船舶、水圧鉄管などの防振に適用される筒状構造
物の防振装置に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vibration isolator for a tubular structure which is applied to the vibration isolation of marine towers, wind turbine towers, ships, hydraulic iron pipes and the like.
【０００２】[0002]
【従来の技術】図５は従来の筒状構造物の一例としての
風車タワーの説明図である。図において、筒状構造物の
風車タワー０２の上部には増速機、発電機などで構成さ
れている機械装置０１が搭載されており、増速機などか
ら発生する振動が風車タワー０２へ伝わり、その振動が
風車タワー０２から大きな騒音となって周囲へ放射され
る。図における符号０５は風車翼である。2. Description of the Related Art FIG. 5 is an explanatory view of a wind turbine tower as an example of a conventional tubular structure. In the figure, a mechanical device 01 including a speed increaser and a generator is mounted on the upper part of the wind turbine tower 02 having a tubular structure, and vibration generated from the speed increaser is transmitted to the wind turbine tower 02. , The vibration becomes a large noise from the wind turbine tower 02 and is radiated to the surroundings. Reference numeral 05 in the figure denotes a wind turbine blade.
【０００３】[0003]
【発明が解決しようとする課題】上記のように従来の筒
状構造物においては、筒状構造物の風車タワー０２に振
動源となる機械装置０１が搭載されていると、機械装置
０１で発生する振動が風車タワー０２へ伝わり、その振
動による大きな騒音が風車タワー０２から周囲へ放射さ
れるため、防振装置により風車タワー０２から放射され
る騒音を低減する必要がある。As described above, in the conventional tubular structure, when the wind turbine tower 02 of the tubular structure is equipped with the mechanical device 01 serving as the vibration source, the mechanical device 01 generates the vibration. The generated vibration is transmitted to the wind turbine tower 02, and a large noise due to the vibration is radiated to the surroundings from the wind turbine tower 02. Therefore, it is necessary to reduce the noise radiated from the wind turbine tower 02 by the vibration isolator.
【０００４】[0004]
【課題を解決するための手段】本発明に係る筒状構造物
の防振装置は上記課題の解決を目的にしており、筒状構
造物の周方向断面と形状が異なり上記周方向断面に連ね
て挿入された複数のブロッキングマスと、該ブロッキン
グマスと振動源との間の筒状構造物面に貼付された制振
材とを備えた構成を特徴とする。SUMMARY OF THE INVENTION A vibration isolator for a tubular structure according to the present invention is intended to solve the above-mentioned problems, and the shape of the tubular structure is different from that of the circumferential direction, and the vibration is connected to the circumferential section. It is characterized in that it comprises a plurality of blocking masses inserted as described above and a damping material attached to the surface of the cylindrical structure between the blocking mass and the vibration source.
【０００５】[0005]
【作用】即ち、本発明に係る筒状構造物の防振装置にお
いては、筒状構造物の周方向断面に周方向断面と形状が
異なる複数のブロッキングマスが連ねて挿入されるとと
もにブロッキングマスと振動源との間の筒状構造物面に
制振材が貼付されており、上流側の振動源からブロッキ
ングマスよりも下流側の筒状構造物へ伝わる振動をブロ
ッキングマスが遮断し制振材がその振動エネルギを吸収
する。That is, in the vibration isolator for a tubular structure according to the present invention, a plurality of blocking masses having a shape different from the circumferential cross section are inserted in a row in the circumferential cross section of the tubular structure, and A damping material is attached to the surface of the cylindrical structure between the vibration source and the damping material that blocks the vibration transmitted from the vibration source on the upstream side to the cylindrical structure on the downstream side of the blocking mass. Absorbs the vibration energy.
【０００６】[0006]
【実施例】図１乃至図４は本発明の一実施例に係る筒状
構造物の防振装置の説明図である。図において、本実施
例に係る筒状構造物の防振装置はマリンタワー、風車タ
ワー、船舶、水圧鉄管などの防振に使用されるもので、
筒状構造物の一例として風力発電装置の風車タワー２に
装着されており、筒状構造物の風車タワー２の上部には
図示しない風車翼や増速機、発電機などで構成されてい
る機械装置などが搭載されているが、図１に示すように
この風車タワー２の断面を一周して風車タワー２の板厚
と著しく断面厚さの異なるブロッキングマス３を環状に
連ねて挿入するとともに、このブロッキングマス３と上
部の機械装置などの振動源との間の風車タワー２内面に
風車タワー２の板厚の２倍程度、或いは２倍以上の厚さ
に通常のコンクリートを塗るようにダンピング効果の大
きいエポキシ系などの制振材４を壁状に塗り付けてい
る。なお、この制振材４は風車タワー２外面、或いは両
面に塗り付けてもよい。ブロッキングマス３は図２に示
すように、振動の遮断効果を発揮させたい下限の周波数
に応じて寸法ａ，ｂを決める。また、ブロッキングマス
３は剛体として機能するように、振動の遮断効果を発揮
させたい上限の周波数に応じて長さを短くし、風車タワ
ー２の円周に沿って配置する。1 to 4 are explanatory views of a vibration isolator for a cylindrical structure according to an embodiment of the present invention. In the figure, the vibration isolator of the tubular structure according to the present embodiment is used for vibration isolation of a marine tower, a windmill tower, a ship, a penstock, etc.
A machine that is mounted on a wind turbine tower 2 of a wind turbine generator as an example of a tubular structure, and is configured with a wind turbine blade, a speed increaser, a generator, etc. (not shown) at the upper part of the wind turbine tower 2 of the tubular structure. Although a device and the like are mounted, as shown in FIG. 1, the cross section of the wind turbine tower 2 is rotated once, and the blocking masses 3 having a cross section thickness significantly different from the plate thickness of the wind turbine tower 2 are inserted in an annular manner. Damping effect is applied to the inner surface of the wind turbine tower 2 between the blocking mass 3 and the vibration source such as the upper mechanical device by applying normal concrete to a thickness of about twice or more than the thickness of the wind turbine tower 2. The damping material 4 made of epoxy or the like having a large size is applied in a wall shape. The damping material 4 may be applied to the outer surface or both surfaces of the wind turbine tower 2. As shown in FIG. 2, the blocking mass 3 determines the dimensions a and b according to the lower limit frequency at which the vibration blocking effect is desired to be exerted. Further, the blocking mass 3 is arranged along the circumference of the wind turbine tower 2 so as to function as a rigid body, the length is shortened according to the upper limit frequency at which the vibration blocking effect is desired to be exerted.
【０００７】このように、風車タワー２の途中に風車タ
ワー２の板厚と断面の厚さが著しく異なるブロッキング
マス３が挿入されており、このブロッキングマス３は振
動を低減させようとする風車タワー２の振動および騒音
の上限の周波数に応じて剛体として機能するように小さ
く複数個に分割して風車タワー２の断面円周上に配置さ
れている。また、上部の機械装置などの振動源とこのブ
ロッキングマス３との間の風車タワー２にはダンピング
効果の大きい制振材４が貼付けられている。ブロッキン
グマス３は上部の機械装置などの振動源から風車タワー
２内を伝わる振動を風車タワー２の途中で遮断するもの
で、振動源とブロッキングマス３との間の風車タワー２
に振動源から伝わる振動エネルギを閉じ込めて上流側の
振動源からブロッキングマス３よりも下流側の風車タワ
ー２へ振動が伝わらないように遮断する。さらに、振動
源とブロッキングマス３との間の風車タワー２に貼り付
けられている制振材４がそのダンピング効果により振動
エネルギを吸収して振動を減衰させることにより、風車
タワー２全体から放射される騒音を低減させることがで
きる。As described above, the blocking mass 3 having a plate thickness and a cross-section thickness remarkably different from each other is inserted in the middle of the wind turbine tower 2, and the blocking mass 3 is intended to reduce vibration. 2 are arranged on the circumference of the cross section of the wind turbine tower 2 by being divided into a plurality of small parts so as to function as a rigid body according to the upper limit frequency of vibration and noise. Further, a damping material 4 having a large damping effect is attached to the wind turbine tower 2 between the vibration source such as an upper mechanical device and the blocking mass 3. The blocking mass 3 blocks the vibration transmitted from the vibration source such as an upper mechanical device in the wind turbine tower 2 in the middle of the wind turbine tower 2, and the wind turbine tower 2 between the vibration source and the blocking mass 3.
The vibration energy transmitted from the vibration source is confined to block the vibration from the vibration source on the upstream side so that the vibration does not propagate to the wind turbine tower 2 on the downstream side of the blocking mass 3. Further, the damping material 4 attached to the wind turbine tower 2 between the vibration source and the blocking mass 3 absorbs the vibration energy by the damping effect and attenuates the vibration, so that it is radiated from the entire wind turbine tower 2. Noise can be reduced.
【０００８】図３に風車タワー２などの筒状構造物の板
厚ｈ、ブロッキングマス３の寸法ａ，ｂをパラメータに
して振動の遮断効果を計算した一例を示す。上流の筒状
構造物から伝わる振動をブロッキングマスにより下流の
筒状構造物へ伝えないように遮断する場合、筒状構造物
の板厚に比べてブロッキングマス断面の厚さを著しく大
きくすることによって遮断効果がある。この計算結果に
基づき、振動および騒音の低減を図ろうとする下限の周
波数に応じてブロッキングマスの寸法ａ，ｂを決定する
が、基本的には振動を遮断しようとする下限の周波数が
低ければ、ブロッキングマスの寸法を大きくする。ま
た、ブロッキングマスをできるだけ剛体として機能させ
るためには、振動の遮断効果を発揮させようとする上限
の周波数に応じてブロッキングマスの長さを十分に短か
くしておく必要がある。FIG. 3 shows an example in which the vibration blocking effect is calculated using the plate thickness h of the tubular structure such as the wind turbine tower 2 and the dimensions a and b of the blocking mass 3 as parameters. When the vibration transmitted from the upstream tubular structure is blocked by the blocking mass so as not to be transmitted to the downstream tubular structure, the thickness of the blocking mass cross section is significantly increased compared to the thickness of the tubular structure. Has a blocking effect. Based on the calculation result, the dimensions a and b of the blocking mass are determined according to the lower limit frequency for reducing vibration and noise. Basically, if the lower limit frequency for cutting off vibration is low, Increase the size of the blocking mass. In order to make the blocking mass function as a rigid body as much as possible, it is necessary to make the length of the blocking mass sufficiently short according to the upper limit frequency at which the vibration blocking effect is to be exerted.
【０００９】曲げ波の波長λB および剪断波の波長λS
は次式で示される。 λB ＝ＣB ／ｆ，ＣB ＝（Ｂ／ｍ11）1/4 ・（２πｆ）1/2 ………（１） Ｂ＝Ｅｈ3 ／１２（１−ν2 ） ｍ11＝ρｈ λS ＝ＣS ／ｆ，ＣS ＝（Ｅ／ρ）1/2 ………………………………（２） ただし、ｆは周波数、Ｅはヤング率、ｈは板厚、νはポ
アソン比である。例えば、振動を遮断したい上限の周波
数ｆをｆ＝２KHZ とし、材料を板厚６mmの鋼板とする
と、各波長λB ，λS は λB ＝６２０mm、 λS ＝２５５０mm ブロッキングマスを剛体とみなせるその波長に比べて十
分に短かい長さとして例えばその１／４とすると、ブロ
ッキングマスの長さは約１５０mmとすればよい。振動の
遮断効果の計算にはブロッキングマス両側の板を半無限
梁として扱っており、ブロッキングマスの取付け距離Ｌ
を振動を遮断したい下限の周波数の波長に比べて十分に
大きくする必要がある。下限の周波数を例えば２００Ｈ
Z とすると、その場合の曲げ波の波長λB は（１）式を
用いて λB ＝５４０mm ブロッキングマスの取付け距離は曲げ波の波長に比べて
十分に長い距離とし、例えばその波長の４倍とすると約
２０００mmとなる。The bending wave wavelength λ B and the shear wave wavelength λ S
Is given by the following equation. λ B = C B / f, C B = (B / m 11) 1/4 · (2πf) 1/2 ......... (1) B = Eh 3/12 (1-ν 2) m 11 = ρh λ S = C S / f, C S = (E / ρ) 1/2 ………………………… (2) where f is frequency, E is Young's modulus, h is plate thickness, ν Is the Poisson's ratio. For example, the frequency f of the upper to be cut off vibrations and f = 2KH Z, considered the material when the steel sheet having a thickness of 6 mm, the wavelength lambda B, lambda S is lambda B = 620 mm, rigid the lambda S = 2550 mm blocking mass Assuming that the length is sufficiently shorter than the wavelength, for example, 1/4 of the length, the length of the blocking mass may be about 150 mm. The plates on both sides of the blocking mass are treated as semi-infinite beams in the calculation of the vibration blocking effect.
Is required to be sufficiently larger than the wavelength of the lower limit frequency at which vibration is to be cut off. The lower limit frequency is, for example, 200H
Let Z be the wavelength λ B of the bending wave in that case, using equation (1) λ B = 540 mm The mounting distance of the blocking mass should be sufficiently longer than the wavelength of the bending wave, for example 4 times that wavelength. Then, it becomes about 2000 mm.
【００１０】このように、振動および騒音を低減させた
い下限の周波数および上限の周波数に応じてブロッキン
グマスの寸法並びに取付け位置を計算により決定し、効
果的な振動の遮断を実現することができ、上部の機械装
置などの振動源から伝わる振動はブロッキングマスによ
り筒状構造物内に閉じ込められ、下流側の筒状構造物へ
の振動の伝達を大きく低減させることができる。さら
に、筒状構造物にダンピング効果の大きい制振材４を施
工することにより、その振動を大きく低減させることが
できる。例えば、制振材の施工前後の損失率をそれぞれ
η1 ，η2 とすると、施工による概略の低減量ΔＬは ΔＬ＝１０log η2 ／η1 このような制振材４による振動のダンピング効果とブロ
ッキングマスによる振動の遮断効果とを組合わせること
により、筒状構造物全体から放射される騒音を顕著に低
減させることができる。As described above, the size and mounting position of the blocking mass can be determined by calculation according to the lower limit frequency and the upper limit frequency at which vibration and noise are desired to be reduced, and effective vibration isolation can be realized. The vibration transmitted from the vibration source such as the upper mechanical device is confined in the cylindrical structure by the blocking mass, and the transmission of the vibration to the downstream cylindrical structure can be greatly reduced. Further, by applying the damping material 4 having a large damping effect to the tubular structure, the vibration can be greatly reduced. For example, assuming that the loss rates before and after construction of the damping material are η 1 and η 2 , respectively, the approximate reduction amount ΔL due to construction is ΔL = 10log η 2 / η 1 and the damping effect of vibration by such damping material 4 is By combining the effect of blocking the vibration by the blocking mass, the noise radiated from the entire tubular structure can be significantly reduced.
【００１１】[0011]
【発明の効果】本発明に係る筒状構造物の防振装置は前
記のように構成されており、ブロッキングマスよりも下
流側の筒状構造物へ伝わる振動をブロッキングマスが遮
断し制振材がその振動エネルギを吸収するので、筒状構
造物から周囲へ放射される騒音が低減する。The vibration isolator for a cylindrical structure according to the present invention is configured as described above, and the blocking mass blocks the vibration transmitted to the cylindrical structure on the downstream side of the blocking mass, and the damping material. Absorbs the vibration energy, so that the noise emitted from the cylindrical structure to the surroundings is reduced.
【図１】図１（ａ）は本発明の一実施例に係る筒状構造
物の防振装置の正面図、同図（ｂ）は平面図である。FIG. 1 (a) is a front view of a vibration isolator for a tubular structure according to an embodiment of the present invention, and FIG. 1 (b) is a plan view.
【図２】図２はそのブロッキングマスの斜視図である。FIG. 2 is a perspective view of the blocking mass.
【図３】図３はこれらの作用説明図である。FIG. 3 is an explanatory view of these actions.
【図４】図４もこれらの作用説明図である。FIG. 4 is also an explanatory diagram of these actions.
【図５】図５は従来の風車タワーの正面図である。FIG. 5 is a front view of a conventional wind turbine tower.
２ 風車タワー ３ ブロッキングマス ４ 制振材 2 Windmill tower 3 Blocking mass 4 Damping material
フロントページの続き (72)発明者 今村 矗洋 長崎市深堀町５丁目717番１号 三菱重工 業株式会社長崎研究所内 (72)発明者 岩永 洋一 長崎市飽の浦町１番１号 三菱重工業株式 会社長崎造船所内 (72)発明者 窪谷 達雄 長崎市飽の浦町１番１号 三菱重工業株式 会社長崎造船所内 (72)発明者 松浪 雄二 長崎市飽の浦町１番１号 三菱重工業株式 会社長崎造船所内Front page continuation (72) Inventor Akihiro Imamura 5-717-1, Fukahori-cho, Nagasaki City, Nagasaki Research Institute, Mitsubishi Heavy Industries, Ltd. (72) Inventor Yoichi Iwanaga 1-1, Atsunoura-machi, Nagasaki City Nagasaki Mitsubishi Heavy Industries Ltd. Inside the shipyard (72) Inventor Tatsuo Kubota 1-1 1-1 Atsunoura-machi, Nagasaki-shi Nagasaki Shipyard Co., Ltd. (72) Inventor Yuji Matsunami 1-1 1-1 Atsunoura-machi, Nagasaki-shi Nagasaki Shipyard Co., Ltd.
Claims (1)
上記周方向断面に連ねて挿入された複数のブロッキング
マスと、該ブロッキングマスと振動源との間の筒状構造
物面に貼付された制振材とを備えたことを特徴とする筒
状構造物の防振装置。1. A plurality of blocking masses which are different in shape from the circumferential cross section of the tubular structure and are inserted in succession in the circumferential cross section, and affixed to the surface of the tubular structure between the blocking mass and the vibration source. A vibration damping device for a cylindrical structure, comprising:
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP00159794A JP3342148B2 (en) | 1994-01-12 | 1994-01-12 | Anti-vibration device for cylindrical structures |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP00159794A JP3342148B2 (en) | 1994-01-12 | 1994-01-12 | Anti-vibration device for cylindrical structures |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH07208540A true JPH07208540A (en) | 1995-08-11 |
| JP3342148B2 JP3342148B2 (en) | 2002-11-05 |
Family
ID=11505915
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP00159794A Expired - Fee Related JP3342148B2 (en) | 1994-01-12 | 1994-01-12 | Anti-vibration device for cylindrical structures |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3342148B2 (en) |
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|---|---|---|---|---|
| JP2013087633A (en) * | 2011-10-13 | 2013-05-13 | Osaka Gas Co Ltd | Noise reduction method for wind turbine generator and noise reduced wind turbine generator |
| CN103216393A (en) * | 2012-01-19 | 2013-07-24 | 周登荣 | Silencing device of wind power generation tower |
| CN103321854A (en) * | 2013-05-29 | 2013-09-25 | 国家电网公司 | Vibration control method for wind generator set tower |
| WO2017008714A1 (en) * | 2015-07-10 | 2017-01-19 | 北京金风科创风电设备有限公司 | Heat dissipation retaining structure for heat production device, installation method thereof, and wind turbine generator set |
| JP2017077864A (en) * | 2015-10-22 | 2017-04-27 | 三菱重工業株式会社 | Vessel |
| CN111350630A (en) * | 2020-03-08 | 2020-06-30 | 北京工业大学 | Multi-wind wheel multi-directional energy collection type wind power generator tower adopting multi-dimensional vibration damper |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN102828922A (en) * | 2012-08-22 | 2012-12-19 | 上海泰胜风能装备股份有限公司 | Mounting device for pendulum damper of wind turbine tower |
| WO2014125593A1 (en) | 2013-02-14 | 2014-08-21 | 三菱重工業株式会社 | Wind turbine generator |
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1994
- 1994-01-12 JP JP00159794A patent/JP3342148B2/en not_active Expired - Fee Related
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
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| JP2013087633A (en) * | 2011-10-13 | 2013-05-13 | Osaka Gas Co Ltd | Noise reduction method for wind turbine generator and noise reduced wind turbine generator |
| CN103216393A (en) * | 2012-01-19 | 2013-07-24 | 周登荣 | Silencing device of wind power generation tower |
| CN103216393B (en) * | 2012-01-19 | 2015-03-18 | 周登荣 | Silencing device of wind power generation tower |
| CN103321854A (en) * | 2013-05-29 | 2013-09-25 | 国家电网公司 | Vibration control method for wind generator set tower |
| WO2017008714A1 (en) * | 2015-07-10 | 2017-01-19 | 北京金风科创风电设备有限公司 | Heat dissipation retaining structure for heat production device, installation method thereof, and wind turbine generator set |
| US10914538B2 (en) | 2015-07-10 | 2021-02-09 | Beijing Goldwind Science & Creation Windpower Equipment Co., Ltd | Heat dissipation retaining structure for heat production device, installation method thereof, and wind turbine generator set |
| JP2017077864A (en) * | 2015-10-22 | 2017-04-27 | 三菱重工業株式会社 | Vessel |
| CN111350630A (en) * | 2020-03-08 | 2020-06-30 | 北京工业大学 | Multi-wind wheel multi-directional energy collection type wind power generator tower adopting multi-dimensional vibration damper |
| CN111350630B (en) * | 2020-03-08 | 2021-06-04 | 北京工业大学 | Multi-wind wheel multi-directional energy collection type wind power generator tower adopting multi-dimensional vibration damper |
Also Published As
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| JP3342148B2 (en) | 2002-11-05 |
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