EP0349384B1 - Method and apparatus for actively controlling combustion instability - Google Patents

Method and apparatus for actively controlling combustion instability Download PDF

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Publication number
EP0349384B1
EP0349384B1 EP19890401754 EP89401754A EP0349384B1 EP 0349384 B1 EP0349384 B1 EP 0349384B1 EP 19890401754 EP19890401754 EP 19890401754 EP 89401754 A EP89401754 A EP 89401754A EP 0349384 B1 EP0349384 B1 EP 0349384B1
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EP
European Patent Office
Prior art keywords
means
fact
combustion
compression chamber
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.)
Revoked
Application number
EP19890401754
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German (de)
French (fr)
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EP0349384A1 (en
Inventor
Thierry Poinsot
François Lacas
Jean Chambon
Denis Veynante
Arnaud-Christophe Trouve
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Centre National de la Recherche Scientifique CNRS
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Centre National de la Recherche Scientifique CNRS
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Publication date
Family has litigation
Priority to FR8808383 priority Critical
Priority to FR8808383A priority patent/FR2633370B1/en
Priority to FR8902902A priority patent/FR2645247B2/en
Priority to FR8902902 priority
Application filed by Centre National de la Recherche Scientifique CNRS filed Critical Centre National de la Recherche Scientifique CNRS
Publication of EP0349384A1 publication Critical patent/EP0349384A1/en
Application granted granted Critical
Publication of EP0349384B1 publication Critical patent/EP0349384B1/en
First worldwide family litigation filed litigation Critical https://patents.darts-ip.com/?family=26226745&utm_source=google_patent&utm_medium=platform_link&utm_campaign=public_patent_search&patent=EP0349384(B1) "Global patent litigation dataset” by Darts-ip is licensed under a Creative Commons Attribution 4.0 International License.
Anticipated expiration legal-status Critical
Application status is Revoked legal-status Critical

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    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23NREGULATING OR CONTROLLING COMBUSTION
    • F23N5/00Systems for controlling combustion
    • F23N5/16Systems for controlling combustion using noise-sensitive detectors
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23NREGULATING OR CONTROLLING COMBUSTION
    • F23N1/00Regulating fuel supply

Description

  • La présente invention concerne un dispositif de contrôle actif des instabilités de combustion. The present invention relates to an active control system of combustion instabilities.
  • Les instabilités de combustion sont des oscillations de forte amplitude qui apparaissent dans les chambres de combustion d'installations telles que des moteurs d'avion, des moteurs fusées, des fours ou des brûleurs industriels. Combustion instabilities are oscillations of high amplitude that appear in facilities combustion chambers such as aircraft engines, rocket engines, furnaces or industrial burners. Ces oscillations sont extrêmement nocives et peuvent entraîner la baisse des performances du système, l'augmentation du bruit émis, et même, dans certains cas, la destruction complète du foyer par suite des vibrations engendrées. These oscillations are extremely harmful and can lead to lower system performance, increased noise emitted, and even, in some cases, the complete destruction of the home as a result of vibration generated.
  • FR-A- 1 155 063 décrit un dispositif permettant de détecter des instabilités de combustion dans une chambre de combustion et comprenant un microphone sensible aux caractéristiques de fluctuation de la fréquence acoustique qui accompagne la production de la flamme et une cellule photo-électrique sensible aux caractéristiques de fluctuation de la lumière de la flamme. FR-A- 1155063 discloses a device for detecting combustion instabilities in a combustion chamber and comprising a microphone sensitive to the fluctuation characteristics of the acoustic frequency which accompanies the production of the flame and a photoelectric cell sensitive to fluctuation in characteristics of the light from the flame. Il s'agit dans ce document d'un dispositif permettant de détecter des instabilités de combustion mais non pas d'en réaliser le contrôle actif. It is in this document a device for detecting combustion instabilities but not to achieve active control.
  • GB-A-1 495 015 décrit un dispositif de contrôle actif des instabilités de combustion dans une chambre de combustion connectée à une ligne d'alimentation en carburant, comprenant des moyens de détection pour détecter des instabilités de combustion dans ladite chambre de combustion, une chambre de compression à membrane, possédant des orifices d'entrée et de sortie connectés respectivement à des parties amont et aval de ladite ligne d'alimentation en carburant, et des moyens pour faire vibrer la membrane de manière à faire varier le volume de la chambre de compression et contrôler le débit de carburant injecté dans ladite chambre de compression, et des moyens de commande connectés aux moyens de vibration et recevant le signal délivré par lesdits moyens de détection. GB-A-1495015 describes an active control system of the combustion instabilities in a combustion chamber connected to a fuel supply line, comprising detector means for detecting instabilities of combustion in said combustion chamber, a membrane compression chamber, having inlet and outlet ports connected to upstream and downstream portions respectively of said fuel supply line, and means for vibrating the diaphragm so as to vary the volume of the chamber compression and control the flow of fuel injected into said compression chamber, and control means connected to the means of vibration and receiving the signal delivered by said detection means. Dans ce document, il est prévu d'utiliser en plus du signal fourni par les moyens de détection un autre signal, à savoir un signal de base carré ayant la même fréquence, et délivré par un circuit électronique séparé. In this document, it is intended to use in addition to the signal supplied by the detection means a further signal, namely a square basic signal having the same frequency, and issued by a separate electronic circuit. On mesure la différence de phase entre le signal de base carré et le signal de sortie des moyens de détection et l'on délivre le signal de base modifié aux moyens faisant vibrer la membrane de la chambre de compression. Measuring the phase difference between the square base signal and the output signal detection means and it outputs the base signal modified means vibrating the membrane of the compression chamber.
  • Outre le fait qu'il est nécessaire de prévoir un circuit distinct pour produire le signal de base carré le dispositif connu n'est pas auto-régulé car il est nécessaire de connaître préalablement la fréquence d'oscillation du signal de base carré afin d'effectuer un contrôle des instabilités de combustion. Besides the fact that it is necessary to provide a separate circuit to produce the square basic signal the known device is not self-regulated because it is necessary to know beforehand the oscillation frequency of the square basic signal in order to performing a control of combustion instabilities.
  • La présente invention se propose de réaliser un dispositif plus simple et plus fiable de contrôle actif des instabilités de combustion en réalisant une modulation directe du débit de carburant par le signal délivré par les moyens de détection. The present invention proposes to produce a simpler and more reliable device for active control of combustion instability by providing a direct modulation of the fuel flow by the signal delivered by the detection means.
  • Les caractéristiques de l'invention font l'objet des revendications 1 et 2. The characteristics of the invention are subject matter of claims 1 and 2.
  • Les moyens de détection peuvent comprendre, par exemple, un microphone monté dans la chambre de combustion, ou un capteur optique monté pour détecter les oscillations de la flamme dans cette chambre. The detection means may comprise, for example, a microphone mounted in the combustion chamber, or an optical sensor mounted for detecting the oscillations of the flame in this room.
  • Selon un mode de réalisation préféré de l'invention, la chambre de compression qui posséde au moins une paroi de fond constituée par une membrane, et des moyens pour faire vibrer la membrane de manière à faire varier le volume de la chambre, comporte une pluralité d'orifices d'entrée et d'orifices de sortie formés symétriquement radialement dans la paroi latérale de la chambre. According to a preferred embodiment of the invention, the compression chamber which has at least a bottom wall constituted by a membrane, and means for vibrating the diaphragm so as to vary the volume of the chamber, has a plurality of inlet ports and outlet ports formed radially symmetrically in the lateral wall of the chamber.
  • Cette caractéristique permet d'éviter de solliciter les modes acoustiques de la cavité. This feature allows to avoid straining the acoustic modes of the cavity.
  • En outre, la chambre de compression à volume variable est totalement indépendante du brûleur et peut être montée à une certaine distance de ce dernier. In addition, the compression chamber of variable volume is completely independent of the burner and can be mounted at a certain distance therefrom. En conséquence, son installation ne nécessite aucune modification structurelle de la chambre de combustion et ne change ni ses caractéristiques ni ses performances. Therefore, its installation requires no structural modification of the combustion chamber and does not change its characteristics or its performance.
  • En ce qui concerne les moyens permettant de faire vibrer la membrane, ils peuvent être constitués par un dispositif électromagnétique ou par tout dispositif mécanique susceptible d'atteindre les fréquences d'instabilité de la flamme, généralement de l'ordre de quelques centaines de Hertz. As regards the means for vibrating the membrane, they may be constituted by an electromagnetic device or by any mechanical device capable of achieving the frequency instability of the flame, usually of the order of a few hundred Hertz.
  • Dans un mode de réalisation particulier, la chambre possède une forme symétrique autour d'un axe de révolution, par exemple sensiblement cylindrique. In a particular embodiment, the chamber has a symmetrical shape about an axis of revolution, for example substantially cylindrical.
  • On décrira maintenant à titre d'exemple non limitatif un mode de réalisation particulier de l'invention en référence aux dessins annexés dans lesquels : will now be described by way of non-limitative example a particular embodiment of the invention with reference to the accompanying drawings in which:
    • la figure 1 est une représentation schématique d'un dispositif selon l'invention, Figure 1 is a schematic representation of a device according to the invention,
    • La figure 2 est une vue éclatée de la chambre à volume variable et, Figure 2 is an exploded view of the variable volume chamber and,
    • la figure 3 est un diagramme représentant les résultats obtenus avec un dispositif de ce type. Figure 3 is a diagram showing the results obtained with a device of this type.
  • La figure 1 représente une chambre de combustion 1 alimentée en air par un conduit d'aspiration 2 et en carburant par une ligne d'alimentation 3 connectée à un brûleur 4. 1 shows a combustion chamber 1 supplied with air by a suction conduit 2 and fuel through a supply line 3 connected to a burner 4.
  • Afin de supprimer les instabilités de combustion dans la chambre 1, des microphones 5, 5' sont montés dans cette chambre et sur le conduit 2 respectivement et sont reliés à des moyens de commande 6 tels qu'une bague à retard ou un calculateur dont la sortie est appliquée à l'entrée d'un amplificateur 7 commandant les moyens de contrôle de débit 8 montés sur la ligne d'alimentation en carburant 3. In order to suppress combustion instabilities in the chamber 1, the microphones 5, 5 'are mounted in this chamber and the pipe 2 respectively, and are connected to control means 6 such as a delay ring or a computer whose output is applied to the input of an amplifier 7 controlling the flow control means 8 mounted on the fuel supply line 3.
  • Les moyens de contrôle 8 sont constitués par un actionneur formant une chambre cylindrique 10 possédant une paroi de fond rigide 11 et une autre paroi de fond 12 constituée par une membrane élastique susceptible de vibrer sous l'effet d'un électro-aimant connecté à la sortie de l'amplificateur 7. The control means 8 are constituted by an actuator forming a cylindrical chamber 10 having a rigid bottom wall 11 and another bottom wall 12 formed by an elastic membrane capable of vibrating under the effect of an electromagnet connected to the output of the amplifier 7.
  • Une bride 13 permet la fixation de cette membrane. A flange 13 allows the fixing of this membrane.
  • L'arrivée et le départ du carburant dans la chambre 10 s'effectuent par l'intermédiaire d'orifices 14 répartis symétriquement par rapport à l'axe 15 de la chambre 10 dans un même plan perpendiculaire à cet axe. The arrival and departure of the fuel in the chamber 10 are carried through holes 14 distributed symmetrically about the axis 15 of the chamber 10 in the same plane perpendicular to this axis.
  • Ces orifices sont constitués par des buses radiales 16 engagées dans la paroi latérale 17 de la chambre. These openings are formed by radial nozzles 16 engaged in the side wall 17 of the chamber.
  • Dans l'exemple représenté aux dessins, trois buses d'entrée de carburant et trois buses de sortie de carburant ont été prévues, les buses d'entrée et les buses de sortie étant par exemple intercalées. In the example shown in the drawings, three fuel inlet nozzles and three fuel discharge nozzles are provided, the inlet and outlet nozzles nozzles being e.g. interleaved.
  • Bien entendu, les buses d'entrée sont toutes raccordées à la partie amont de la ligne d'alimentation 3 tandis que les buses de sortie sont toutes raccordées à la partie aval de cette ligne. Of course, the inlet nozzles are all connected to the upstream portion of the feed line 3, while the outlet nozzles are all connected to the downstream portion of that line.
  • Les oscillations détectées par le microphone 5 sont donc renvoyées à la ligne d'alimentation 3 par l'intermédiaire de la ligne à retard 6, de manière à moduler le débit de carburant injecté dans la chambre par le brûleur 4. The oscillations detected by the microphone 5 are thus returned to the power supply line 3 through the delay line 6, so as to modulate the flow of fuel injected into the chamber by the burner 4.
  • On a pu constater qu'un tel dispositif permet de supprimer totalement les instabilités de combustion dans le cas d'un brûleur laminaire. It was found that such a device totally eliminates the combustion instabilities in the case of laminar burner.
  • La figure 3 montre les résultats obtenus dans le cas d'un brûleur turbulent. Figure 3 shows the results obtained in the case of a turbulent burner.
  • Cette figure représente le niveau de bruit mesuré en Pascals en fonction du temps de retard en millisecondes appliqué par la ligne à retard 6. This figure shows the noise level measured in Pascals as a function of milliseconds delay time applied by the delay line 6.
  • En l'absence de dispositif de contrôle, le niveau de bruit était égal à 200 Pa (soit environ 140 dB acoustiques) et la fréquence de l'instabilité était de 280 Hz (soit une période de 3,6 ms). In the absence of control device, the noise level was 200 Pa (about 140 acoustic dB) and frequency instability was 280 Hz (representing a period of 3.6 ms).
  • Par contre, lorsque le procédé selon l'invention est mis en oeuvre, le bruit est réduit de moitié sur une très large gamme de valeurs de déphasage. For against, when the method according to the invention is implemented, the sound is halved over a very wide range of phase shift values. Cette gamme (de 13 à 14,2 ms) correspond environ à 1/3 de la période du phénomène, et montre que le système est peu sensible à des variations de paramètres. This range (from 13 to 14.2 ms) corresponds approximately to 1/3 of the period of the phenomenon, and shows that the system is insensitive to parameter variations.
  • En fait, une analyse spectrale non représentée révèle que le bruit résiduel est dû à la combustion turbulente mais que l'instabilité à 280 Hz a disparu. In fact, not shown spectral analysis reveals that the residual noise due to turbulent combustion, but that instability to 280 Hz has disappeared. De plus, une observation de la chambre de combustion par strioscopie ultrarapide (10000 images/seconde) montre que les oscillations des flammes qui étaient la source de l'instabilité ont aussi disparu. In addition, observation of the combustion chamber by flash Schlieren (10,000 frames / second) shows that the oscillations of the flames that were the source of instability have also disappeared.
  • Il a en outre été constaté que l'invention permettait d'étendre le domaine de fonctionnement du brûleur, notamment vers les très faibles puissances. It has further been found that the invention allows to extend the operating range of the burner, particularly to the very low power.
  • D'autres moyens de contrôle du débit de carburant pourraient être utilisés, par exemple une vanne rotative ou une restriction réglable dans la canalisation 3. Other fuel flow control means could be used, for example a rotary valve or an adjustable restriction in the pipe 3.

Claims (8)

  1. A device for the active control of instabilities of combustion in a combustion chamber (1) connected to a fuel supply line (3), comprising detector means (5, 5') for detecting instabilities of combustion in the said combustion chamber (1), a compression chamber (8) having a diaphragm (12) and inlet and outlet orifices (14) connected respectively to upstream and downstream portions of the said fuel supply line (3), and means of making the diaphragm vibrate so as to make the volume of the compression chamber vary and control the flow of fuel injected into the said compression chamber (8), and control means (6) connected to the means of vibration and receiving the signal delivered by the said detector means (5, 5'), characterized by the fact
    that the control means (6) comprise a delay line, receive as the sole input signal the signal delivered by the detector means (5, 5') and delay this signal and deliver the delayed signal to the means of vibration.
  2. A device for the active control of instabilities of combustion in a combustion chamber (1) connected to a fuel supply line (3), comprising detector means (5, 5') for detecting instabilities of combustion in the said combustion chamber (1), a compression chamber (8) having a diaphragm (12) and inlet and outlet orifices (14) connected respectively to upstream and downstream portions of the said fuel supply line (3), and means of making the diaphragm vibrate so as to make the volume of the compression chamber vary and control the flow of fuel injected into the said compression chamber (8), and control means (6) connected to the means of vibration and receiving the signal delivered by the said detector means (5, 5'), characterized by the fact
    that the control means (6) comprise a microprocessor which receives as the sole input signal the signal delivered by the detector means (5, 5'), processes this signal by a transfer function and delivers the processed signal to the means of vibration.
  3. A device as in either of the preceding Claims, characterized by the fact that the said detector means (5, 5') comprise a microphone mounted in the combustion chamber (1) or upstream of the latter for detecting the variations in pressure in the said combustion chamber (1).
  4. A device as in either of the Claims 1 and 2, characterized by the fact that the said detector means (5, 5') comprise an optical pick-up mounted so as to detect the oscillations of the flame in the combustion chamber (1).
  5. A device as in any one of the Claims 1 to 4, characterized by the fact that the said means of vibration comprise at least one electromagnet.
  6. A device as in any one of the preceding Claims, characterized by the fact that the inlet and outlet orifices (14) are formed with radical symmetry in the sidewall (17) of the compression chamber (8).
  7. A device as in any ore of the preceding Claims, characterized by the fact that the said compression chamber (8) has a symmetrical shape about an axis of revolution (15).
  8. A device as in Claim 7, characterized by the fact that the compression chamber (8) is substantially cylindrical.
EP19890401754 1988-06-22 1989-06-21 Method and apparatus for actively controlling combustion instability Revoked EP0349384B1 (en)

Priority Applications (4)

Application Number Priority Date Filing Date Title
FR8808383 1988-06-22
FR8808383A FR2633370B1 (en) 1988-06-22 1988-06-22 Method and active control device of the combustion instabilities
FR8902902A FR2645247B2 (en) 1988-06-22 1989-03-06 Method and active control device of the combustion instabilities
FR8902902 1989-03-06

Publications (2)

Publication Number Publication Date
EP0349384A1 EP0349384A1 (en) 1990-01-03
EP0349384B1 true EP0349384B1 (en) 1995-04-12

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EP19890401754 Revoked EP0349384B1 (en) 1988-06-22 1989-06-21 Method and apparatus for actively controlling combustion instability

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US (1) US5145355A (en)
EP (1) EP0349384B1 (en)
JP (1) JPH0285607A (en)
AT (1) AT121179T (en)
DE (2) DE68922149T2 (en)
FR (1) FR2645247B2 (en)

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JP2880398B2 (en) * 1994-03-18 1999-04-05 株式会社山武 Combustion control system
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US6560967B1 (en) 1998-05-29 2003-05-13 Jeffrey Mark Cohen Method and apparatus for use with a gas fueled combustor
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DE19942387A1 (en) * 1999-07-14 2001-01-18 Abb Alstom Power Ch Ag A method for burning a liquid fuel in a combustion system and combustion system for carrying out the method
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JP3810615B2 (en) * 2000-05-18 2006-08-16 三菱重工業株式会社 Turbine remote control method and system
JP4056232B2 (en) * 2001-08-23 2008-03-05 三菱重工業株式会社 Gas turbine control device, gas turbine system, and gas turbine remote monitoring system
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US9366433B2 (en) * 2010-09-16 2016-06-14 Emerson Electric Co. Control for monitoring flame integrity in a heating appliance
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Also Published As

Publication number Publication date
EP0349384A1 (en) 1990-01-03
DE68922149D1 (en) 1995-05-18
FR2645247B2 (en) 1991-06-07
FR2645247A2 (en) 1990-10-05
JPH0285607A (en) 1990-03-27
US5145355A (en) 1992-09-08
AT121179T (en) 1995-04-15
DE68922149T2 (en) 1995-10-26

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