EP1522062B1 - Dispositif et procede d'insonorisation active et groupe motopropulseur pour avions - Google Patents

Dispositif et procede d'insonorisation active et groupe motopropulseur pour avions Download PDF

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Publication number
EP1522062B1
EP1522062B1 EP03787640A EP03787640A EP1522062B1 EP 1522062 B1 EP1522062 B1 EP 1522062B1 EP 03787640 A EP03787640 A EP 03787640A EP 03787640 A EP03787640 A EP 03787640A EP 1522062 B1 EP1522062 B1 EP 1522062B1
Authority
EP
European Patent Office
Prior art keywords
chamber
gas stream
gas
deflection
deflection device
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 - Fee Related
Application number
EP03787640A
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German (de)
English (en)
Other versions
EP1522062A1 (fr
Inventor
Jörgen ZILLMANN
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Airbus Defence and Space GmbH
Original Assignee
EADS Deutschland GmbH
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by EADS Deutschland GmbH filed Critical EADS Deutschland GmbH
Publication of EP1522062A1 publication Critical patent/EP1522062A1/fr
Application granted granted Critical
Publication of EP1522062B1 publication Critical patent/EP1522062B1/fr
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

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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
    • G10K11/172—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general using resonance effects

Definitions

  • the present invention relates to an active noise control apparatus according to the preamble of claim 1, the use of such a device in an engine, in particular an aircraft engine, an active noise control method and an aircraft engine.
  • An active technology is eg. in the journal aeroacoustics volume 1, number 1, 2002, p. 53.
  • loudspeakers in the form of oscillating membranes are used to generate a secondary sound field, which extinguishes the primary sound field.
  • the speakers or actuators are arranged in the immediate vicinity of the generation of sound of the primary sound field, namely on the Statorblättem an engine.
  • the generated levels are very low due to the limited available installation volume, so that only a very small proportion of the primary sound field can be reduced. That is, in acoustic actuators, the generation of high sound levels is hardly possible because size, weight and power consumption are too high for many applications.
  • tones are suppressed, which arise through the flow of cavities.
  • the sound is caused by instabilities in the flow.
  • the cavities strongly stimulate these disturbances for certain frequencies, resulting in very loud sounds.
  • actuators are used.
  • the resonator properties are influenced in such a way that the instability of the flow is not stimulated.
  • the interaction of instability with the resonant properties of the chamber is suppressed.
  • U1 anti-sound is generated in an exhaust duct with a loudspeaker. It is located between the speaker and the exhaust duct, a chamber to create an overpressure in front of the speaker and thus protect the speaker from aggressive gases, combustion residues, dust, etc. from the exhaust duct.
  • JP 06348280 also describes an anti-noise system in a gas channel.
  • the active noise control device comprises a housing in which a chamber is formed, and a chamber opening formed in a wall of the chamber, the chamber opening being arranged or disposable laterally on a gas flow, and at the chamber opening being an adjustable deflection device is arranged, which in a first position at least partially passes the gas stream flowing past the chamber opening in the chamber to compress the gas there, and in a second position, the gas from the chamber supplies the gas stream to the gas in the chamber relax.
  • the device according to the invention has a very high efficiency.
  • the necessary energy is taken from the gas or air flow, whereby this air flow can be constant.
  • To control only a small power is needed, which is only used to divert the air flow.
  • the structure of the device according to the invention is relatively simple and requires only little space and weight.
  • the present invention utilizes an aeroacoustic sound generation mechanism to generate high sound pressure, which is also responsible for tone generation when whistling pipes and cavities.
  • the sound is triggered by instabilities in the free boundary layer flow.
  • These pressure and velocity fluctuations of the flow are coupled with an acoustic resonator.
  • the resonator which is formed by the chamber, causes a feedback of the fluctuation components to the place of origin of the free boundary layer. For certain frequencies, this response generates the resonator Feedback conditions that increase instability, that is, resonate. After a certain settling time, this process generates strong pressure fluctuations in the resonator and emits them as sound.
  • the instability has fanned so far that the free boundary layer flow is in the resonator volume and deflected in the rhythm of the resonance frequency. This is the cause of the compression of the fluid particles. It is exploited that the conversion of velocity fluctuations in acoustic pressure fluctuations in the resonator volume is a very effective process. The fluid particles are immediately compressed and decompressed, which characterizes the actual sound generation mechanism.
  • the present invention takes advantage of these effects in advance, in order to reduce the sound in a flow or in a flow channel.
  • the stochastic excitation due to the instability in the boundary layer flow is dispensed with and a deflecting device is used in its place. This device allows a deterministic stimulation of the sound generation process, and / or deflection of the air flow in the chamber volume.
  • this sound generator is suitable for active sound control.
  • the frequency of the radiated sound can be determined by the time duration during which the deflection unit is in the first and in the second position.
  • the phase of the sound pressure fluctuations is in fixed relation to the phase of the introduced air flow into the chamber.
  • the deflection device comprises a flap, which is arranged pivotably about an axis, wherein the axis is directed perpendicular to the flow direction of the gas flow.
  • the deflection device can also be designed as a cantilevered, swingable plate.
  • the chamber is configured as a resonator, wherein the deflection device is positioned at an upstream edge of the chamber opening.
  • the air flow is deflected in proportion to the excitation signal of the deflection device.
  • a flow channel for the gas flow is arranged, which serves to pass the gas flow past the chamber opening.
  • the flow channel can either be a part of the device according to the invention, or the device according to the invention is designed such that an existing flow channel, for example in an engine, is used correspondingly.
  • the deflection device comprises a deflection surface, which faces the gas flow in the first position and is directed obliquely to the gas flow, and which faces away from the gas flow in the second position and is directed obliquely to the gas flow.
  • the device comprises a control and / or drive unit, which is coupled to the deflection device.
  • the deflection device can, for example comprise an elastic element.
  • a restoring force is exerted on the deflection device, which acts in the direction of the zero position, so that the deflection device operates effectively and effectively, even at elevated frequencies.
  • the chamber comprises an adjustable chamber wall.
  • the chamber volume can be adapted to the respective requirements.
  • the sound pressure generated by the device according to the invention during operation depends on the chamber volume and on the amount of air introduced into the chamber.
  • the sound pressure can be adjusted flexibly.
  • gas flow is formed by the inlet flow of an engine.
  • energy required for noise control of engines is taken directly from the gas or air flow, so that no complex power supplies for operating the device are necessary.
  • the gas stream is formed from a separate compressed air supply.
  • the gas or air flow can be generated from existing units, wherein the compressed air supply is an example of such an aggregate.
  • the flow channel can be formed by an engine intake of an aircraft.
  • the device according to the invention in an engine, in particular in an aircraft engine.
  • the inventive method very loud noise levels can be produced to combat noise, although only a small power is necessary for this.
  • the result is a particularly high degree of efficiency, since the energy for the suppression of noise is taken from the available gas or air stream.
  • the inventive method is advantageously carried out with the device according to the invention.
  • it may be performed during operation of an engine.
  • the sound emission of engines can be significantly reduced.
  • the features and advantages mentioned above with regard to the device also apply to the method according to the invention.
  • an aircraft engine which comprises an inventive apparatus for active noise control, as described here.
  • a device 10 for sound absorption in a first phase of operation comprises a housing 11, in the interior of which a chamber 12 is formed.
  • the chamber 12 has in a wall 12 a Chamber opening 13, which is located on one side of the chamber 12, which is swept in operation by an air or gas stream 14.
  • the wall 12a of the chamber 12, in which the chamber opening 13 is located, is aligned parallel to the direction of the gas flow 14 located upstream of the chamber 12.
  • a deflection device 15 is arranged, which in the present example has the shape of a plate.
  • the deflection device 15 is pivotally mounted about an axis A, which is directed perpendicular to the direction of the supplied gas flow 14.
  • the plate-shaped deflection device 15 can assume different positions, which make it possible to direct the gas flow 14 at least partially into the chamber or to supply gas from the chamber 12 to the gas flow 14 leading past the chamber opening 13.
  • the deflection device 15 is tilted relative to the gas flow 14, so that the oncoming gas strikes the inclined bottom 15a of the deflection device 15, so that it is deflected in its flow direction and guided into the chamber 12.
  • an increased pressure or counter-pressure builds up there through the gas flowing into the chamber 12.
  • an edge 16 At the upstream end of the chamber opening 13 is an edge 16, so that the gas from the gas stream 14 due to the deflection or caused by the deflecting device 15 directional change of the flow is guided past the edge 16 and sweeps over the edge 16, if enters the chamber 12 through the chamber opening 13.
  • a flow channel 17 is formed, which serves to guide the gas flow 14 and may be part of the device 10. But it is also possible that the device 10 is connected laterally to an existing flow channel.
  • the chamber 12 has on its one side an adjustable chamber wall 18, so that the chamber volume can be variably adjusted.
  • the adjustable chamber wall 18 is arranged on the side of the chamber 12 opposite the chamber opening 13.
  • a control and drive mechanism is coupled to the adjustable chamber wall 18 to control and adjust the chamber volume as needed.
  • FIG. 1b shows the device 10 in a second phase (90 °) in which the plate-shaped deflection device 15 is directed parallel to the direction of the gas flow 14.
  • the gas flow 14 is not deflected, but he sweeps over the chamber opening 13 above the plate-shaped deflection device 15, so that the gas is guided past the chamber 12.
  • the pressure in the chamber 12 has reached its maximum value.
  • the pressure is symbolized schematically by circles, the diameter representing a measure of the amplitude.
  • the black circles in Fig. 1 b indicate a present in the chamber 12 overpressure with respect to lying outside the chamber 12 areas of the gas flow.
  • Fig. 1c shows the device 10 in a third phase (180 °), in which the deflection device 15 is tilted such that the gas flowing in the flow channel 17 gas is guided past at its top and does not enter the chamber 12, while on the other hand in the Chamber 12 can escape through the chamber opening 13 so that the gas in the chamber can expand. That is, the baffle 15 is inclined with respect to the flow direction of the gas flow 14, so that the chamber opening 13 for the oncoming gas is closed. On the underside 15a of the tilted deflection device 15, the gas is supplied from the chamber 12 to the gas flow past the top.
  • FIG. 1 d shows the device 10 according to the invention in a fourth phase (270 °), in which a pressure minimum exists in the chamber 12.
  • the pressure minimum has arisen in this phase due to the inertia of the expansion process shown in Fig. 1c.
  • the deflection device 15 is again parallel to the direction of the gas flow 14 aligned, so that the gas flow 14 is guided past by means of the deflection device 15 at the chamber opening 13.
  • the negative pressure in the chamber 12 existing in this phase is symbolized by the white circles in FIG. 1d.
  • the cycle starts again from the beginning, i.
  • gas or air is conducted into the chamber 12 by means of the deflection device 15, and the further phases are subsequently passed through.
  • the deflecting device 15 controllably directs the air or gas flow into the chamber 12, and an alternating pressure is generated in the chamber 12 by adjusting the deflecting device 15.
  • the alternating pressure is emitted as sound through the chamber opening 13.
  • the air or gas flow is deflected in proportion to the excitation signal of the deflection device 15.
  • the frequency of the radiated sound is determined by the duration of the phases shown.
  • the phase of the sound pressure fluctuations is in fixed relation to the phase of the introduced gas flow into the chamber 12.
  • the sound pressure depends on the amount of air introduced into the chamber 12 and the chamber volume.
  • the amplitude of the excitation signal for the deflection device 15 is used to control the amount of air introduced.
  • the chamber volume is adjusted by the adjustable chamber wall 18.
  • aeroacoustic sound generation mechanisms are used to combat noise.
  • the required energy is taken from the available gas flow.
  • the gas flow is deflected into the laterally mounted chamber 12, where it is decelerated and compacted due to the limited available chamber volume.
  • the gas flow is conducted past the chamber opening 13, whereby the compressed gas in the chamber 12 can relax via the chamber opening 13.
  • the sound caused by the density change is radiated through the chamber opening 13. It overlaps with the disturbing original sound field and, by suitable control of the phases and frequencies, leads to the partial extinction of the originally present disturbing sound.
  • the structure is very simple and only little space and weight is needed.

Landscapes

  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Acoustics & Sound (AREA)
  • Multimedia (AREA)
  • Exhaust Silencers (AREA)

Claims (18)

  1. Dispositif (10) d'insonorisation active, comprenant un boîtier (11) contenant une chambre (12) avec une ouverture de chambre (13) dans une paroi de la chambre (12) et disposée ou à disposer latéralement à un courant de gaz (14),
    caractérisé par
    un dispositif de renvoi (15) réglable sur l'ouverture de chambre (13), le dispositif de renvoi (15), dans une première position, conduisant le courant de gaz (14) passant à côté de l'ouverture de chambre (13) au moins partiellement dans la chambre (12) pour y comprimer des gaz et, dans une deuxième position, amène les gaz de la chambre (12) dans le courant de gaz (14) pour détendre les gaz présents dans la chambre (12).
  2. Dispositif selon la revendication 1,
    caractérisé en ce que
    le dispositif de renvoi (15) comprend un clapet pivotant autour d'un axe (A) perpendiculairement au sens d'écoulement du courant de gaz (14).
  3. Dispositif selon la revendication 1 ou 2,
    caractérisé en ce que
    le dispositif de renvoi (15) est une plaque oscillante enserrée d'un côté.
  4. Dispositif selon l'une quelconque des revendications précédentes,
    caractérisé en ce que
    la chambre (12) présente la forme d'un résonateur, le dispositif de renvoi (15) étant positionné sur une arête (16) de l'ouverture de chambre (13) située en amont.
  5. Dispositif selon l'une quelconque des revendications précédentes,
    caractérisé par
    un canal d'écoulement (17) pour le courant de gaz (14), qui est disposé en amont de l'ouverture de chambre (13) pour faire passer le courant de gaz (14) à côté de l'ouverture de chambre (13).
  6. Dispositif selon l'une quelconque des revendications précédentes,
    caractérisé en ce que
    le dispositif de renvoi (15) comprend une surface de renvoi (15a) qui, dans la première position, est tournée vers le courant de gaz (14) et orientée en biais par rapport au courant de gaz (14), et qui dans la deuxième position est opposée au courant de gaz (14) et orientée en biais par rapport au courant de gaz (14).
  7. Dispositif selon l'une quelconque des revendications précédentes,
    caractérisé par
    une unité de commande pour commander le dispositif de renvoi (15).
  8. Dispositif selon l'une quelconque des revendications précédentes,
    caractérisé par
    une unité d'entraînement à laquelle le dispositif de renvoi (15) est couplé.
  9. Dispositif selon l'une quelconque des revendications précédentes,
    caractérisé en ce que
    le dispositif de renvoi (15) comprend un élément élastique.
  10. Dispositif selon l'une quelconque des revendications précédentes,
    caractérisé par
    une paroi de chambre (18) réglable.
  11. Dispositif selon l'une quelconque des revendications précédentes,
    caractérisé en ce que
    le courant de gaz (14) est formé par le flux d'entrée d'un propulseur.
  12. Dispositif selon l'une quelconque des revendications précédentes,
    caractérisé en ce que
    le courant de gaz (14) est formé par une alimentation en air comprimé.
  13. Dispositif selon l'une quelconque des revendications précédentes,
    caractérisé en ce que
    le canal d'écoulement (17) est formé par une entrée de propulseur d'un avion.
  14. Utilisation d'un dispositif selon l'une quelconque des revendications précédentes dans un propulseur.
  15. Procédé d'insonorisation active comprenant les étapes:
    - renvoi au moins partiel d'un courant de gaz (14) dans une chambre (12) pour augmenter la pression dans la chambre (12),
    - passage du courant de gaz (14) en dérivation de la chambre (12) lorsqu'une pression maximale à l'intérieur de la chambre (12) est atteinte,
    - retour de gaz de la chambre (12) dans le courant de gaz (14) pour réduire la pression dans la chambre (12),
    - réalisation des étapes périodiques l'une après l'autre.
  16. Procédé selon la revendication 15,
    caractérisé en ce qu'
    on pivote un dispositif de renvoi (15) en forme d'un clapet entre différentes positions pour établir et réduire périodiquement la pression dans la chambre (12).
  17. Procédé selon la revendication 15 ou 16,
    caractérisé en ce qu'
    il est réalisé lors du fonctionnement d'un propulseur.
  18. Propulseur pour avions,
    caractérisé par
    un dispositif d'insonorisation active selon l'une quelconque des revendications 1 à 13.
EP03787640A 2002-07-16 2003-07-09 Dispositif et procede d'insonorisation active et groupe motopropulseur pour avions Expired - Fee Related EP1522062B1 (fr)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
DE10232291 2002-07-16
DE10232291A DE10232291B4 (de) 2002-07-16 2002-07-16 Vorrichtung und Verfahren zur aktiven Schallbekämpfung sowie Triebwerk für Flugzeuge
PCT/DE2003/002292 WO2004017301A1 (fr) 2002-07-16 2003-07-09 Dispositif et procede d'insonorisation active et groupe motopropulseur pour avions

Publications (2)

Publication Number Publication Date
EP1522062A1 EP1522062A1 (fr) 2005-04-13
EP1522062B1 true EP1522062B1 (fr) 2006-03-15

Family

ID=30010087

Family Applications (1)

Application Number Title Priority Date Filing Date
EP03787640A Expired - Fee Related EP1522062B1 (fr) 2002-07-16 2003-07-09 Dispositif et procede d'insonorisation active et groupe motopropulseur pour avions

Country Status (5)

Country Link
US (1) US7273130B2 (fr)
EP (1) EP1522062B1 (fr)
JP (1) JP4361866B2 (fr)
DE (2) DE10232291B4 (fr)
WO (1) WO2004017301A1 (fr)

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2005111993A1 (fr) * 2004-05-14 2005-11-24 Yanmar Co., Ltd. Structure de suppression de bruit de cabine
DE102019106685B4 (de) * 2019-03-15 2021-01-21 Hochschule für Angewandte Wissenschaften Hamburg Schallabsorber mit einem Helmholtz-Resonator

Family Cites Families (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5970868A (ja) * 1982-10-15 1984-04-21 Nippon Denso Co Ltd 容積可変式共鳴消音システム
US5283398A (en) * 1989-12-26 1994-02-01 Tsuchiya Mfg. Co., Ltd. Resonator type silencer
DE4228356C2 (de) * 1992-08-26 1995-10-19 Daimler Benz Aerospace Ag Hohlraumresonator zur Lärmreduzierung
JPH06348280A (ja) 1993-06-03 1994-12-22 Sekisui Chem Co Ltd ダクト用消音装置
DE29611884U1 (de) * 1996-07-09 1997-11-06 ABS Gesellschaft für Automatisierung, Bildverarbeitung und Software mbH, 07745 Jena Einrichtung zur Kompression von Luft oder Gasen mit akustischen Schwingungserzeugern
DE29715756U1 (de) * 1997-09-02 1998-03-19 Lenz, Josef, 85614 Kirchseeon Abgasresonanzsystem mit Klappensteuerung für Verbrennungsmotoren aller Art
US6112514A (en) * 1997-11-05 2000-09-05 Virginia Tech Intellectual Properties, Inc. Fan noise reduction from turbofan engines using adaptive Herschel-Quincke tubes
ES2174642T3 (es) * 1998-08-11 2002-11-01 Siemens Ag Dispositivo para la depuracion catalitica de gas de escape.
DE19853359A1 (de) * 1998-11-19 2000-05-31 Daimler Chrysler Ag Verbrennungsmotor mit Abgasschalldämpfer und Verfahren zu dessen Betrieb
US6069840A (en) 1999-02-18 2000-05-30 The United States Of America As Represented By The Secretary Of The Air Force Mechanically coupled helmholtz resonators for broadband acoustic attenuation
DE19958748B4 (de) * 1999-12-07 2005-07-28 Webasto Ag Vorrichtung zur Beeinflussung der Luftströmung
DE20003519U1 (de) * 2000-02-25 2000-06-08 Wolff Robert Helmholtzresonator
DE10112010B4 (de) * 2001-03-13 2018-03-08 Valeo Klimasysteme Gmbh Luftführungskanal und Kraftfahrzeugs-Heiz-, Belüftungs- und oder Klimaanlage
FR2836513B1 (fr) * 2002-02-25 2005-12-02 Renault Vehicules Ind Ligne d'echappement et vehicule a moteur ainsi equipe
US20040094360A1 (en) * 2002-11-06 2004-05-20 Calsonic Kansei Corporation Acoustic dumper for exhaust system
JP4375088B2 (ja) * 2004-03-31 2009-12-02 トヨタ紡織株式会社 可変消音器制御装置

Also Published As

Publication number Publication date
JP2005538286A (ja) 2005-12-15
DE50302683D1 (de) 2006-05-11
US7273130B2 (en) 2007-09-25
US20050236225A1 (en) 2005-10-27
JP4361866B2 (ja) 2009-11-11
DE10232291B4 (de) 2004-05-27
WO2004017301A1 (fr) 2004-02-26
EP1522062A1 (fr) 2005-04-13
DE10232291A1 (de) 2004-02-05

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