JPH01283498A - Pressure pulsation suppressing device in paper machine pipe line and the like - Google Patents
Pressure pulsation suppressing device in paper machine pipe line and the likeInfo
- Publication number
- JPH01283498A JPH01283498A JP63109945A JP10994588A JPH01283498A JP H01283498 A JPH01283498 A JP H01283498A JP 63109945 A JP63109945 A JP 63109945A JP 10994588 A JP10994588 A JP 10994588A JP H01283498 A JPH01283498 A JP H01283498A
- Authority
- JP
- Japan
- Prior art keywords
- pressure
- frequency
- pulsation
- pressure pulsation
- pipe line
- 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
- 230000010349 pulsation Effects 0.000 title claims abstract description 38
- 239000012530 fluid Substances 0.000 claims abstract description 13
- 239000012528 membrane Substances 0.000 abstract description 6
- 238000010586 diagram Methods 0.000 description 4
- 230000000694 effects Effects 0.000 description 3
- 238000000034 method Methods 0.000 description 3
- 239000007788 liquid Substances 0.000 description 2
- 230000001629 suppression Effects 0.000 description 2
- 230000002238 attenuated effect Effects 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 238000013016 damping Methods 0.000 description 1
- 230000005284 excitation Effects 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
Classifications
-
- G—PHYSICS
- G10—MUSICAL INSTRUMENTS; ACOUSTICS
- G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
- G10K11/00—Methods or devices for transmitting, conducting or directing sound in general; Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
- G10K11/16—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
- G10K11/175—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general using interference effects; Masking sound
- G10K11/178—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general using interference effects; Masking sound by electro-acoustically regenerating the original acoustic waves in anti-phase
- G10K11/1787—General system configurations
- G10K11/17873—General system configurations using a reference signal without an error signal, e.g. pure feedforward
-
- G—PHYSICS
- G10—MUSICAL INSTRUMENTS; ACOUSTICS
- G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
- G10K11/00—Methods or devices for transmitting, conducting or directing sound in general; Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
- G10K11/16—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
- G10K11/175—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general using interference effects; Masking sound
- G10K11/178—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general using interference effects; Masking sound by electro-acoustically regenerating the original acoustic waves in anti-phase
- G10K11/1781—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general using interference effects; Masking sound by electro-acoustically regenerating the original acoustic waves in anti-phase characterised by the analysis of input or output signals, e.g. frequency range, modes, transfer functions
- G10K11/17821—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general using interference effects; Masking sound by electro-acoustically regenerating the original acoustic waves in anti-phase characterised by the analysis of input or output signals, e.g. frequency range, modes, transfer functions characterised by the analysis of the input signals only
- G10K11/17823—Reference signals, e.g. ambient acoustic environment
-
- G—PHYSICS
- G10—MUSICAL INSTRUMENTS; ACOUSTICS
- G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
- G10K11/00—Methods or devices for transmitting, conducting or directing sound in general; Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
- G10K11/16—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
- G10K11/175—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general using interference effects; Masking sound
- G10K11/178—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general using interference effects; Masking sound by electro-acoustically regenerating the original acoustic waves in anti-phase
- G10K11/1785—Methods, e.g. algorithms; Devices
- G10K11/17857—Geometric disposition, e.g. placement of microphones
-
- G—PHYSICS
- G10—MUSICAL INSTRUMENTS; ACOUSTICS
- G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
- G10K2210/00—Details of active noise control [ANC] covered by G10K11/178 but not provided for in any of its subgroups
- G10K2210/10—Applications
- G10K2210/112—Ducts
-
- G—PHYSICS
- G10—MUSICAL INSTRUMENTS; ACOUSTICS
- G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
- G10K2210/00—Details of active noise control [ANC] covered by G10K11/178 but not provided for in any of its subgroups
- G10K2210/30—Means
- G10K2210/301—Computational
- G10K2210/3011—Single acoustic input
-
- G—PHYSICS
- G10—MUSICAL INSTRUMENTS; ACOUSTICS
- G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
- G10K2210/00—Details of active noise control [ANC] covered by G10K11/178 but not provided for in any of its subgroups
- G10K2210/30—Means
- G10K2210/321—Physical
- G10K2210/3212—Actuator details, e.g. composition or microstructure
Landscapes
- Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- Acoustics & Sound (AREA)
- Multimedia (AREA)
- Pipe Accessories (AREA)
- Soundproofing, Sound Blocking, And Sound Damping (AREA)
Abstract
Description
【発明の詳細な説明】
［産業上の利用分野］
本発明は抄紙機の配管系をはじめとするあらゆる流体輸
送を伴う流体配管系に発生する圧力脈動を抑制する装置
にかかるしのである。DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a device for suppressing pressure pulsations occurring in any fluid piping system that involves fluid transport, including the piping system of a paper machine.
［従来の技術］
従来の配管系の脈動威衰手段としては、一般に第３図及
び第４図に示すようなアキュムレータＣが採用されてい
る。すなわち、内部をゴム膜ｄにより気体室Ｃと液体室
「とに仕切られたアキュムレータＣが、配管９の途中に
取り付けられ、該配管９と連通ずる液体室ｆに該配管９
内の流体の脈動が導かれ、気体室ｅ内に封入された気体
の圧縮性により流体の脈動が吸収されるようになってい
る。図中、ｈはオリフィスである。[Prior Art] As a conventional pulsation damping means for a piping system, an accumulator C as shown in FIGS. 3 and 4 is generally employed. That is, an accumulator C whose inside is partitioned into a gas chamber C and a liquid chamber by a rubber membrane d is installed in the middle of a pipe 9, and a liquid chamber f communicating with the pipe 9 is connected to the pipe 9.
The pulsations of the fluid inside are guided, and the pulsations of the fluid are absorbed by the compressibility of the gas sealed in the gas chamber e. In the figure, h is an orifice.
［発明が解決しようとする課題］
しかし、従来の方法ではアキュムレータＣが固有の特性
を持つので、広い周波数範囲で脈動を減衰させることが
難かしい。[Problems to be Solved by the Invention] However, in the conventional method, since the accumulator C has unique characteristics, it is difficult to attenuate pulsations over a wide frequency range.
又、従来のアキュムレータＣは受動形であるため脈動減
衰量には限界があり、更に装置が大型になってしまう。Further, since the conventional accumulator C is a passive type, there is a limit to the amount of pulsation attenuation, and the device becomes larger.
本発明は種々の周波数の脈動を能動的に抑制できる小型
の圧力脈動抑１１１１装置の（）≧供を１］的とする。The present invention aims at (1) providing a compact pressure pulsation suppressor 1111 device that can actively suppress pulsations of various frequencies.
［課題を解決するための手段］
本発明は流体配管の管壁の少なくとも一部に可動壁を設
け、該可動壁にアクチュエータを連結し、前記配管内の
流体圧力を検出する圧力センサを取り付け、該圧カセン
ザの検出圧から流体圧力の脈動の卓越周波数を求める周
波数分析器を設け、該周波数と同一の周波数且つ逆の位
相で前記アクチュエータを駆動するよう構成したことを
特徴とするものである。[Means for Solving the Problems] The present invention provides a movable wall on at least a part of the pipe wall of a fluid pipe, an actuator is connected to the movable wall, and a pressure sensor is attached to detect the fluid pressure in the pipe, The present invention is characterized in that a frequency analyzer is provided to determine the predominant frequency of fluid pressure pulsation from the detected pressure of the pressure sensor, and the actuator is driven at the same frequency and opposite phase as the predominant frequency.
［作 用コ
流体配管内に生じている圧力脈動は圧力センサにより検
出され、周波数分析器により卓越周波数が求められて該
卓越周波数と同一の周波数で逆の位相となるようアクチ
ュエータによって可動壁が振動され、配管内の圧力脈動
が減少される。[Operation] The pressure pulsations occurring in the fluid piping are detected by a pressure sensor, the dominant frequency is determined by a frequency analyzer, and the movable wall is vibrated by an actuator so as to have the same frequency as the dominant frequency and the opposite phase. pressure pulsations in the pipes are reduced.
［実 施 例〕 以下、本発明の実施例を図面を参照しつつ説明する。[Example〕 Embodiments of the present invention will be described below with reference to the drawings.
第１図は本発明の一実施例であり、配管ｌの途中の管壁
２の一部を切欠き、該切欠部３にゴム膜等の可撓性膜４
を張り設け、該可撓性膜４の略中夫に振動板５を固着し
、該振動板５に電気式の加振機６の振動軸７の先端部を
連結する。FIG. 1 shows an embodiment of the present invention, in which a part of the pipe wall 2 in the middle of the pipe 1 is cut out, and a flexible film 4 such as a rubber film is inserted into the cutout 3.
A diaphragm 5 is fixed to approximately the center of the flexible membrane 4, and the tip of a vibration shaft 7 of an electric vibrator 6 is connected to the diaphragm 5.
前記配管ｊの可動部近傍或は若干ｚすれた脈動を抑制し
たい位置に該配管ｌ内の流体の圧力を検出する圧力セン
サ８を設け、該圧力センサ８の検出圧力信号を周波数分
析器９に導いて配管１内の圧力脈動の卓越周波数を求め
、信号発生器１０により前記卓越周波数と同一の周波数
で且つ逆の位相の正弦波信号を発生させ、前記加振Ｊａ
Ｇに送るようにする。A pressure sensor 8 for detecting the pressure of the fluid in the pipe l is installed near the movable part of the pipe j or at a position where pulsation is desired to be suppressed slightly, and the pressure signal detected by the pressure sensor 8 is sent to a frequency analyzer 9. The signal generator 10 generates a sine wave signal with the same frequency and opposite phase as the predominant frequency, and the excitation Ja
Send it to G.
一般に第２図に示すように配管１の離れた２点Ａ、
Ｂにおいて、Ａ点に圧力脈動か存在すると、Ａ点の圧力
脈動に対し周波数か同じで振幅の異なる位を目のずれた
圧力脈動がＢ点で観測される。Generally, as shown in Fig. 2, two distant points A on the piping 1,
At point B, if pressure pulsations are present at point A, pressure pulsations having the same frequency but different amplitude from the pressure pulsations at point A will be observed at point B.
該Ｂ点において圧力センサ８により圧力を検出し、周波
数分析器９により周波数分析すると圧力脈動の周波数が
求められ、信号発生器１０により前記周波数の正弦波を
所定の振幅と位１１１で加振機６に送られ、振動軸７及
び振動板５が駆動されて、可撓性膜４が振動され、圧力
脈動が減退される。The pressure is detected by the pressure sensor 8 at the point B, and the frequency is analyzed by the frequency analyzer 9 to determine the frequency of the pressure pulsation, and the signal generator 10 generates a sine wave of the frequency at a predetermined amplitude and position 111 using an exciter. 6, the vibration shaft 7 and the vibration plate 5 are driven, the flexible membrane 4 is vibrated, and the pressure pulsation is reduced.
圧力センサ８により検出して周波数分析器９により分析
された圧力脈動の周波数から、信号発生器１０で発生さ
せる加振機６人力信号の周波数は、例えば以下のように
決めることができる。From the frequency of the pressure pulsation detected by the pressure sensor 8 and analyzed by the frequency analyzer 9, the frequency of the human force signal of the vibrator 6 generated by the signal generator 10 can be determined, for example, as follows.
すなわち、信号発生器１０の信号は、
ｕ−ｕｏｓｉｎ（ωを十〇）
で、該ωはＢ点の圧力信号を周波数分析して決める。ｕ
Ｏとθの決め方は試行錯誤的に行なう。That is, the signal of the signal generator 10 is u-uosin (ω is 10), and ω is determined by frequency analysis of the pressure signal at point B. u
O and θ are determined by trial and error.
例えば、ＬＪＱを操業に影響しない程度の小さい振幅に
固定し、θをθ〜３６０’まで変化させ、Ｂ点の圧力脈
動が最も小さくなるθで固定し、今度はｕＯを大きくし
ていき圧力脈動が最小となる値でθを固定するとよい。For example, fix LJQ to a small amplitude that does not affect operation, change θ from θ to 360', fix it at θ where the pressure pulsation at point B is the smallest, and then increase uO and the pressure pulsation It is preferable to fix θ at a value that minimizes θ.
一般に操業条件が変わればωは変化するが、本発明によ
ればその都度ωを更新すればよい。Generally, ω changes when operating conditions change, but according to the present invention, ω can be updated each time.
又、以上の例ではωは一つの場合であったが、圧力脈動
の中に卓越した周波数成分が複数あっても、それぞれの
成分（ω１．ω２．ω３・・・）に上記の方法を適用す
ることができ、それらの重ね合せで圧力脈動を抑制する
ことができる。Also, in the above example, ω is one, but even if there are multiple prominent frequency components in the pressure pulsation, the above method can be applied to each component (ω1, ω2, ω3, etc.). By overlapping them, pressure pulsation can be suppressed.
信号発生器ＩＯでは、
ｕ −ｕ １ｓｉｎ （ω１ ｔ＋θ１）＋ＬＩｒｓｉ
ｎ（ω２ ｔ＋０２）十・・・とし、ω１．ω２・・・
は周波数分析器９で決める。In the signal generator IO, u −u 1sin (ω1 t+θ1)+LIrsi
Let n(ω2 t+02) ten... and ω1. ω2...
is determined by the frequency analyzer 9.
ｕｌ＋ＬＩ２・・・及びθ１、θ２・・・は上記試行錯
誤法で決定する。ul+LI2... and θ1, θ2... are determined by the trial and error method described above.
なお、本発明は上述の実施例のみに限定されるものでは
なく、可動壁及びアクチュエータを複数対備えてもよい
こと等本発明の要旨を逸脱しない範囲内において種々変
更を加え得ることは勿論である。It should be noted that the present invention is not limited to the above-described embodiments, and it goes without saying that various changes may be made without departing from the gist of the present invention, such as the possibility of providing multiple pairs of movable walls and actuators. be.
［発明の効果］
以上説明したように本発明の抄紙機配管系等の圧力脈動
抑制装置によれば、下記の如き種々の優れた効果を発揮
する。[Effects of the Invention] As explained above, the pressure pulsation suppressing device for a paper machine piping system or the like of the present invention exhibits various excellent effects as described below.
ＣＩ＞ アクチュエータにより可動壁を作動させるよ
うにしたので、能動的に大きな脈動減衰を行なえるので
、圧力脈動抑１．す効果が大きい。CI> Since the movable wall is actuated by an actuator, large pulsation attenuation can be actively performed, so pressure pulsation can be suppressed.1. The effect is great.
（ＩＩ） 従来の受動形に比べて圧力脈動抑制効果が
大きいので、装置をコンパクトにできる。そのため取付
位１１ｔの制約か少なく、最も効果のある場所に取り付
けることができる。(II) Since the pressure pulsation suppression effect is greater than that of conventional passive types, the device can be made more compact. Therefore, there are fewer restrictions on the mounting position 11t, and it can be mounted at the most effective location.
［相］ 圧力脈動の周波数を分析し卓越周波数と同一の
族６１数で逆位相の振動により脈動を抑制する方式であ
るため、圧力脈動の発生原因によらずどのような圧力脈
動も減衰させることができる。[Phase] This method analyzes the frequency of pressure pulsations and suppresses the pulsations by vibrations in the same group 61 as the dominant frequency and in the opposite phase, so any pressure pulsations can be attenuated regardless of the cause of the pressure pulsations. I can do it.
詰 圧力脈動抑制部位に圧力センサを設け、該圧力セン
サの」二流側に可動壁及びアクチュエータを設けること
かできるので、設置スペース上の制約かない。Since a pressure sensor can be provided at the pressure pulsation suppression site and a movable wall and an actuator can be provided on the second flow side of the pressure sensor, there are no restrictions on installation space.
・第】図は本発明の装置の一実施例の説明図、第２因は
第１図に示した装置の作動原理を示す図、第３図は従来
のアキュムレータの一例を示す図、第４図は第３図に示
したアキュムレータの内部詳細図である。
■は配管、４は可撓性膜、５は振動板、６は加振機、８
は圧力センサ、９は周波数分析器、１０は信号発生器を
示す。- Figure 4 is an explanatory diagram of one embodiment of the device of the present invention, the second figure is a diagram showing the operating principle of the device shown in Figure 1, Figure 3 is a diagram showing an example of a conventional accumulator, and Figure 4 is a diagram showing an example of the conventional accumulator. The figure is a detailed internal view of the accumulator shown in FIG. 3. ■ is piping, 4 is a flexible membrane, 5 is a diaphragm, 6 is an exciter, 8
9 is a pressure sensor, 9 is a frequency analyzer, and 10 is a signal generator.
Claims (1)
該可動壁にアクチュエータを連結し、前記配管内の流体
圧力を検出する圧力センサを取り付け、該圧力センサの
検出圧から流体圧力の脈動の卓越周波数を求める周波数
分析器を設け、該周波数と同一の周波数且つ逆の位相で
前記アクチュエータを駆動するよう構成したことを特徴
とする抄紙機配管系等の圧力脈動抑制装置。1) Providing a movable wall on at least a part of the pipe wall of the fluid piping,
An actuator is connected to the movable wall, a pressure sensor is attached to detect the fluid pressure in the pipe, and a frequency analyzer is provided to determine the dominant frequency of fluid pressure pulsation from the pressure detected by the pressure sensor. A pressure pulsation suppressing device for a paper machine piping system, etc., characterized in that the actuator is configured to drive the actuator at a frequency and in an opposite phase.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63109945A JPH01283498A (en) | 1988-05-06 | 1988-05-06 | Pressure pulsation suppressing device in paper machine pipe line and the like |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63109945A JPH01283498A (en) | 1988-05-06 | 1988-05-06 | Pressure pulsation suppressing device in paper machine pipe line and the like |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH01283498A true JPH01283498A (en) | 1989-11-15 |
Family
ID=14523098
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP63109945A Pending JPH01283498A (en) | 1988-05-06 | 1988-05-06 | Pressure pulsation suppressing device in paper machine pipe line and the like |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH01283498A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE4441217A1 (en) * | 1993-12-17 | 1995-06-29 | Escher Wyss Gmbh | Economic process effectively damps fluid, esp. pulp, pressure surges |
| EP2063414A1 (en) * | 2007-11-15 | 2009-05-27 | GE-Hitachi Nuclear Energy Americas LLC | Acoustic load mitigator |
-
1988
- 1988-05-06 JP JP63109945A patent/JPH01283498A/en active Pending
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE4441217A1 (en) * | 1993-12-17 | 1995-06-29 | Escher Wyss Gmbh | Economic process effectively damps fluid, esp. pulp, pressure surges |
| DE4441217C2 (en) * | 1993-12-17 | 1998-09-10 | Voith Sulzer Papiermasch Gmbh | Method for damping pressure surges and device for carrying out the method |
| EP2063414A1 (en) * | 2007-11-15 | 2009-05-27 | GE-Hitachi Nuclear Energy Americas LLC | Acoustic load mitigator |
| US8068575B2 (en) | 2007-11-15 | 2011-11-29 | Ge-Hitachi Nuclear Energy Americas Llc | Acoustic load mitigator |
| US9574693B2 (en) | 2007-11-15 | 2017-02-21 | Ge-Hitachi Nuclear Energy Americas Llc | Acoustic load mitigator |
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