EP0985882A1 - Amortissement des vibrations dans des combusteurs - Google Patents

Amortissement des vibrations dans des combusteurs Download PDF

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Publication number
EP0985882A1
EP0985882A1 EP98810901A EP98810901A EP0985882A1 EP 0985882 A1 EP0985882 A1 EP 0985882A1 EP 98810901 A EP98810901 A EP 98810901A EP 98810901 A EP98810901 A EP 98810901A EP 0985882 A1 EP0985882 A1 EP 0985882A1
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EP
European Patent Office
Prior art keywords
combustion chamber
fluid
supply device
fluid supply
recirculation
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
Application number
EP98810901A
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German (de)
English (en)
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EP0985882B1 (fr
Inventor
Jakob Prof. Dr. Keller
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.)
General Electric Technology GmbH
Original Assignee
ABB Schweiz AG
ABB Asea Brown Boveri Ltd
Asea Brown Boveri AB
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 ABB Schweiz AG, ABB Asea Brown Boveri Ltd, Asea Brown Boveri AB filed Critical ABB Schweiz AG
Priority to DE59810347T priority Critical patent/DE59810347D1/de
Priority to EP98810901A priority patent/EP0985882B1/fr
Priority to US09/392,791 priority patent/US6430933B1/en
Publication of EP0985882A1 publication Critical patent/EP0985882A1/fr
Application granted granted Critical
Publication of EP0985882B1 publication Critical patent/EP0985882B1/fr
Anticipated expiration legal-status Critical
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    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23RGENERATING COMBUSTION PRODUCTS OF HIGH PRESSURE OR HIGH VELOCITY, e.g. GAS-TURBINE COMBUSTION CHAMBERS
    • F23R3/00Continuous combustion chambers using liquid or gaseous fuel
    • F23R3/42Continuous combustion chambers using liquid or gaseous fuel characterised by the arrangement or form of the flame tubes or combustion chambers
    • F23R3/54Reverse-flow combustion chambers
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23CMETHODS OR APPARATUS FOR COMBUSTION USING FLUID FUEL OR SOLID FUEL SUSPENDED IN  A CARRIER GAS OR AIR 
    • F23C9/00Combustion apparatus characterised by arrangements for returning combustion products or flue gases to the combustion chamber
    • F23C9/006Combustion apparatus characterised by arrangements for returning combustion products or flue gases to the combustion chamber the recirculation taking place in the combustion chamber
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23MCASINGS, LININGS, WALLS OR DOORS SPECIALLY ADAPTED FOR COMBUSTION CHAMBERS, e.g. FIREBRIDGES; DEVICES FOR DEFLECTING AIR, FLAMES OR COMBUSTION PRODUCTS IN COMBUSTION CHAMBERS; SAFETY ARRANGEMENTS SPECIALLY ADAPTED FOR COMBUSTION APPARATUS; DETAILS OF COMBUSTION CHAMBERS, NOT OTHERWISE PROVIDED FOR
    • F23M20/00Details of combustion chambers, not otherwise provided for, e.g. means for storing heat from flames
    • F23M20/005Noise absorbing means
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23RGENERATING COMBUSTION PRODUCTS OF HIGH PRESSURE OR HIGH VELOCITY, e.g. GAS-TURBINE COMBUSTION CHAMBERS
    • F23R3/00Continuous combustion chambers using liquid or gaseous fuel
    • F23R3/02Continuous combustion chambers using liquid or gaseous fuel characterised by the air-flow or gas-flow configuration
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23RGENERATING COMBUSTION PRODUCTS OF HIGH PRESSURE OR HIGH VELOCITY, e.g. GAS-TURBINE COMBUSTION CHAMBERS
    • F23R3/00Continuous combustion chambers using liquid or gaseous fuel
    • F23R3/28Continuous combustion chambers using liquid or gaseous fuel characterised by the fuel supply
    • F23R3/286Continuous combustion chambers using liquid or gaseous fuel characterised by the fuel supply having fuel-air premixing devices
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F05INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
    • F05BINDEXING SCHEME RELATING TO WIND, SPRING, WEIGHT, INERTIA OR LIKE MOTORS, TO MACHINES OR ENGINES FOR LIQUIDS COVERED BY SUBCLASSES F03B, F03D AND F03G
    • F05B2260/00Function
    • F05B2260/96Preventing, counteracting or reducing vibration or noise
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23RGENERATING COMBUSTION PRODUCTS OF HIGH PRESSURE OR HIGH VELOCITY, e.g. GAS-TURBINE COMBUSTION CHAMBERS
    • F23R2900/00Special features of, or arrangements for continuous combustion chambers; Combustion processes therefor
    • F23R2900/00014Reducing thermo-acoustic vibrations by passive means, e.g. by Helmholtz resonators

Definitions

  • the invention relates to devices and methods for damping acoustic and / or thermoacoustic vibrations in combustion chambers, in particular in combustion chambers of Gas turbines.
  • combustion chambers are nowadays predominantly from the point of view of the lowest possible pollutant formation and thus the lowest possible pollutant emissions in the operation of the combustion chamber.
  • nitrogen oxides are generated during combustion, which, depending on the atmospheric level at which they are emitted, in particular cause a breakdown or an increase in the ozone.
  • Nitrogen oxides (NO x ) are formed at very high temperatures. Such high temperatures occur during combustion, in particular when there is a low excess of air and thus a rich combustion. Such conditions exist, for example, in the case of insufficient atomization and gasification of a liquid fuel in the immediate vicinity of fuel droplets.
  • combustion chambers are now mostly designed as premix combustion chambers.
  • the fuel which is mostly gaseous in stationary gas turbines, is first mixed with air in a premixing device before the actual combustion.
  • the premixing device often consists of one or more burners, as are described, for example, in the publication DE 43 04213 A1.
  • the air supplied to the combustion therefore flows completely or almost completely through one or more burners at the entrance to the combustion chamber.
  • a fuel / air mixture that is as homogeneous as possible is formed in the combustion chamber. Local over-greasing of the fuel / air mixture can thus be largely avoided.
  • nitrogen oxide formation is significantly reduced.
  • the combustion chamber in turn had a high damping property with regard to acoustic and / or thermoacoustic vibrations of the combustion chamber, which were dampened dissipatively.
  • Acoustic and / or thermoacoustic vibrations occur in combustion chambers as a result of different causes. For example, non-uniformities in the temperature distribution of the combustion flow when passing through the turbine lead to non-uniformities in the pressure due to a spatially or temporarily non-uniform enthalpy conversion and thus to thermoacoustic vibrations. These vibrations cannot be prevented in principle.
  • Helmholtz resonators are mostly connected to the combustion chamber on the inlet side. However, Helmholtz resonators only work in a narrow one Frequency band around a fundamental frequency, so there is no broadband damping of different oscillation frequencies.
  • the invention is therefore based on the object, acoustic and / or thermoacoustic Vibrations in a combustion chamber of a turbomachine, in particular a gas turbine, to effectively attenuate over the largest possible frequency range.
  • the combustion chamber at least one Fluid supply device and a combustion chamber and further comprises the combustion chamber
  • At least one attenuation of acoustic and / or thermoacoustic vibrations Has recirculation opening.
  • the recirculation opening creates for acoustic and / or thermoacoustic vibrations a local pressure equalization, so that there is a destructive interference comes from acoustic waves and their reflections.
  • a perfect pressure equalization would of course require that the flow rate just disappear.
  • the Recirculation opening usefully opens into the inflow of the fluid to the Combustion chamber, thus expediently in the fluid supply device. Furthermore, the Recirculation opening also open into another volume.
  • the fluid flowing out of the combustion chamber flows into the fluid inflow with the fluid flow flowing into the combustion chamber is transported further. This is what happens a re-inflow into the combustion chamber and consequently a recirculation of the fluid flowing out of the combustion chamber. But it can also, if appropriate Pressure conditions, fluid from the fluid inflow through the recirculation opening in the Flow into the combustion chamber. Without restricting both possible directions of flow through In the following, however, the recirculation opening is usually only the outflow viewed from fluid in the Brerm space.
  • At least part of the fluid supply device advantageously runs directly adjacent the outside of the combustion chamber wall. Simultaneously with the supply of a fluid, mostly air, the combustion chamber of the combustion chamber is due to this arrangement
  • the combustion chamber wall is convectively cooled on the outside of the combustion chamber.
  • the fluid in the In this case, the fluid supply device therefore flows in the opposite direction Flow in the combustion chamber.
  • the fluid supply device advantageously opens into a Antechamber and from this into the combustion chamber. The aim here is that this Pre-chamber forms a flow state of the fluid that is as homogeneous as possible.
  • the Flow state of the fluid relates to the static pressure, the temperature and the Flow velocity of the fluid.
  • the prechamber can also be omitted.
  • the fluid expediently flows completely or almost completely on the inlet side, preferably to the combustion chamber via a front panel arranged on the inlet side. Often it is The combustion chamber is cylindrical or circular, with the front panel the combustion chamber limited on the entry side. Due to the complete or almost complete supply of the Fluids to the combustion chamber via the front panel are those running in the combustion chamber Combustion from the outset for a low pollutant combustion process sufficient amount of fluid available.
  • the combustion chamber is also advantageous as a premix combustion chamber with a Premixing device executed.
  • a premixing takes place in the premixing device of the mostly gaseous fuel with air instead.
  • the one that is preferably designed as a burner Premixing device is expediently arranged in front of the combustion chamber and preferably opens out in the level of the front panel in the combustion chamber.
  • the recirculation opening is preferably arranged in the front area of the combustion chamber on the combustion chamber wall and / or the front panel.
  • the arrangement of the recirculation opening in the front area of the combustion chamber has the effect that the acoustic oscillation has a pressure node in the area of a main combustion zone.
  • the combustion chamber thus represents an at least partially open vibration chamber in the front area.
  • the recirculation opening is with the Fluid supply device and / or the pre-chamber connected. Occurs as a result of an acoustic and / or thermoacoustic vibration fluid through the recirculation opening from the Combustion chamber, this fluid thus opens into the fluid supply device and / or Antechamber. From there, the fluid flowing out of the combustion chamber flows back into the Combustion chamber. The fluid exiting the combustion chamber consequently recirculates.
  • the recirculation opening is expediently designed as a nozzle, the nozzle advantageously being in the fluid supply device and / or the pre-chamber opens.
  • the nozzle preferably has a constant cross-section so that the fluid flowing out of the combustion chamber is neither significantly accelerated or decelerated. This can be done from the combustion chamber using the nozzle outflowing fluid targeted the flow in the fluid supply device and / or Antechamber to be fed. In particular the direction of flow from the combustion chamber outflowing fluids and the location of the junction are freely selectable.
  • the recirculation opening first opens into a volume and only indirectly through it Volume in the fluid supply device and / or the prechamber, in general, unless specifically differentiated, the confluence of the intermediate volume in the fluid supply device and / or the antechamber as well as the mouth of the To consider recirculation opening in the fluid supply device and / or the prechamber.
  • the recirculation opening is preferably designed such that the narrowest cross section of the Recirculation opening compared to the narrowest cross section of a corresponding one Helmholtz resonator is significantly larger.
  • a corresponding Helmholtz resonator is through the natural acoustic frequency of the combustion chamber and thus the design frequency of the Helmholtz resonators and the required damping performance determined.
  • the narrowest cross section of the recirculation opening preferably has a cross-sectional area on, which is about ten times the cross-sectional area of the narrowest cross-section of the corresponding Helmholtz resonator corresponds.
  • This larger cross-sectional area of the Recirculation opening compared to a Helmholtz resonator is mainly below that Aspect of the widest possible effective range in relation to those to be damped Vibration frequencies and vibration amplitudes advantageous.
  • the muffler proposed here does not lead to a resonant Sound absorption. Therefore the open damper cross section must be the same Damping performance can be about an order of magnitude larger.
  • the flow of real fluid through the combustion chamber is fundamentally lossy.
  • the fluid flowing in the combustion chamber thus has a lower total pressure than that Fluid in the fluid supply device or in the prechamber. Is it due to a static pressure drop for fluid to flow out through the recirculation opening the combustion chamber into the fluid supply device and / or the pre-chamber, this indicates fluid flowing out of the combustion chamber thus has a lower total pressure than the fluid in the fluid supply device and / or the prechamber.
  • This causes the middle one Total pressure in the fluid supply device and / or the antechamber downstream of the junction the recirculation opening in the event of fluid flowing out of the combustion chamber.
  • At least one injector is arranged in the combustion chamber so that it is in a Area downstream of the recirculation opening into the fluid supply device and / or the Antechamber opens.
  • the injector's job is to adjust the total pressure drop Flow over the burner, thus the total pressure gradient of the flow between the Junction of the recirculation opening in the fluid supply device and / or Antechamber and the corresponding level in the combustion chamber, at least to compensate.
  • the fluid additionally supplied by means of the injector is advantageously supplied with a the flow direction adapted to the surrounding fluid flow is introduced into the flow.
  • the injector is expediently designed as a nozzle with a tapering cross section.
  • the mean total pressure of the fluid in increases the fluid supply device and / or the antechamber, in particular downstream of the junction of the injector. This results in a stable pressure rise in the suction branch of the injector just compensated for the pressure drop across the burner.
  • Both the fluid supply device and the injector are particularly expedient and fed the same fluid reservoir.
  • the respective free ends of the Fluid supply device and the injector connected to this fluid reservoir.
  • the combustion chamber advantageously has the largest possible damping volume.
  • the damping volume can be designed, for example, as a damping chamber.
  • the damping volume is arranged such that at least part of the fluid flowing out of the combustion chamber through the recirculation opening flows into the damping volume.
  • the damping volume is expediently connected to the fluid supply device and / or the prechamber.
  • the damping volume preferably has an approximately equal or greater volume than the primary zone of the combustion chamber.
  • the primary zone is the area of the combustion chamber in which the primary combustion takes place. It has been found that the combination of a recirculation opening with a damping volume in the form of a buffer volume leads to particularly effective vibration damping, in particular in the case of a compressible fluid.
  • the damping volume in particular the inflow and outflow to the damping volume, is preferably designed such that the fluid in the damping volume has a balanced static pressure in comparison with the fluid in the combustion chamber at base load and a slightly lower static pressure at full load. With base load, this results in no or only a very small flow through the recirculation openings into the damping volume. At full load, the slight excess pressure in the combustion chamber leads to a continuous outflow of fluid from the combustion chamber through the recirculation opening. Such a design ensures that no fluid flows through the recirculation opening into the combustion chamber at full load. An inflow of fluid through the recirculation opening into the combustion chamber would result in a higher pollutant emission from the combustion chamber.
  • colder fluid expediently flows, for example from the fluid supply device and / or the antechamber, into the damping volume. This avoids excessive temperatures in the damping volume.
  • the volume of the damping volume can be changed. This allows the damping characteristics of the damping volume to be changed and optimized in a simple manner.
  • the narrowest cross section of the Venturi nozzle is preferred in the immediate area of the mouth of the recirculation opening arranged.
  • the venturi nozzle is advantageous in the area of the confluence of the damping volume Fluid supply device arranged and the narrowest cross section of the Venturi nozzle is preferably in the immediate area of the confluence of the damping volume in the Fluid supply device.
  • FIG. 1 an embodiment of the invention is shown in a longitudinal section through a combustion chamber.
  • the combustion chamber consists of a fluid supply device 110, a pre-chamber 111 and a combustion chamber 112. Furthermore, the combustion chamber shown is designed as a pre-mixing combustion chamber with a pre-mixing device 114.
  • the premixing device 114 is arranged on the front on the front panel 115 of the combustion chamber 112.
  • the combustion chamber shown can be designed both as a tubular combustion chamber with a cylindrical cross section or as an annular combustion chamber with a hole circle cross section concentric about the machine axis. The latter embodiment is often preferred in modern turbomachinery, which are usually very compact.
  • the fluid 100 is supplied to the combustion chamber 112 with the aid of the fluid supply device 110.
  • the fluid supply device 110 can consist of individual pipelines which either open into the prechamber 111 or directly into the combustion chamber 112. In the case of annular combustion chambers, in particular, an embodiment of the fluid supply device 110 in the form of one or more circular flow channels is preferred. This ensures that the flow to the combustion chamber is as uniform as possible over the circumference of the combustion chamber.
  • the fluid flows through the fluid supply device 110 in the illustration from right to left and thus in the counterflow direction to the actual flow through the combustion chamber 112. According to the illustration, the fluid flows out of the fluid supply device 110 into the prechamber 111. On the one hand, the fluid in the prechamber 111 flows into the opposite one Directed flow direction.
  • the pre-mixing device 114 which is designed in the form of a plurality of burners distributed around the circumference, is also arranged in the prechamber 111.
  • the premixing device 114 serves for premixing the mostly gaseous fuel with a portion of the supplied fluid 100, mostly air. As a result of the high flow rate in the premixing device 114, no combustion occurs here.
  • the aim of the premixing device 114 is to produce a uniform fuel-fluid mixture.
  • the fluid flows through the front panel 115 of the combustion chamber into the combustion chamber 112.
  • the combustion 101 of the fuel-fluid mixture takes place in the combustion chamber 112.
  • fluid is no longer fed to combustion chamber 112 via additional openings in the hub-side and housing-side wall 113 of the combustion chamber.
  • this additional fluid was mainly used to cool the combustion chamber wall.
  • the hub-side and housing-side combustion chamber wall 113 shown in FIG. 1 is closed. Fluid is no longer mixed along the combustion chamber 112 of the internal combustion chamber flow. This results in a reduced generation of nitrogen oxides during combustion.
  • the equally reduced damping property of the combustion chamber has a disadvantageous effect on acoustic or thermoacoustic vibrations of the fluid flow in the combustion chamber.
  • Such vibrations arise as a result of various causes in combustion chambers, some of which have been described above. Firing up or damping only takes place depending on the acoustic behavior of the combustion chamber. In many cases, this leads to excessive pressure amplitudes of the vibration.
  • the disadvantageous consequences are, in particular, an increase in pollutant emissions due to uneven combustion and an increased mechanical load on the components due to the pressure change amplitudes that arise. In the worst case, the flame may even go out or even flash back. This is where the invention comes in. In the section of the combustion chamber shown in FIG.
  • a recirculation opening 120, 120 ' was arranged on both the housing-side and the hub-side wall of the combustion chamber 112 in the front region of the combustion chamber.
  • the recirculation openings 120, 120 ′ are designed here as nozzles each with a constant cross section and open into the fluid supply device 110.
  • the nozzles are advantageously curved such that the confluence of the fluid 121 emerging from the combustion chamber 112 into the fluid supply device 110 is adapted to the flow of the fluid 100 in the fluid supply device 110.
  • the invention can also be carried out by arranging only one recirculation opening.
  • a distribution of the recirculation openings 120, 120 ′ that is as symmetrical and uniform as possible is advantageous.
  • the distribution of the recirculation openings on the circumference of the combustion chamber is not shown in FIG.
  • Recirculation openings are preferably arranged on the circumference of the annular combustion chamber at a plurality of positions, expediently at equal distances from one another.
  • the design of the recirculation openings 120, 120 'and the fluid supply device 110 at the locations of the openings of the recirculation openings 120, 120' takes place with the aspect that the fluid in the region of the openings of the recirculation openings 120, 120 'compared to the fluid in the combustion chamber 112 has a balanced static pressure at base load and a slightly lower static pressure at full load. This ensures that during normal operation of the combustion chamber between base load and full load, no or only a very small fluid mass flow flows through the recirculation openings 120, 120 'into the combustion chamber 112. In most cases, fluid flows out of combustion chamber 112 to a small extent.
  • the flow velocities in the confluence areas of the recirculation openings 120, 120 ' can be freely selected as design parameters for this by the structural design of the flow cross sections of the fluid supply device 110 in these areas.
  • pressure compensation takes place via the recirculation openings 120, 120 ′ between the fluid flow in the combustion chamber 112 and the fluid flow in the fluid supply device 110 and thus also in the prechamber 111.
  • Fluid 121 emerging from the combustion chamber 112 into the fluid supply device 110 is fed back into the combustion chamber 112 through the prechamber 111 and consequently recirculates.
  • the vibration is damped due to dissipative losses of the recirculating fluid 121.
  • the forced pressure equalization in the primary zone of the combustion chamber leads to destructive interference of the sound waves and therefore to small pressure oscillation amplitudes in the area of the main combustion zone. If the flow cross sections of the recirculation openings 120, 120 'are dimensioned sufficiently large and there is a sufficient pressure drop in the recirculation range, vibrations over the entire frequency range are thus damped or even completely damped out.
  • the viscosity of the fluid total pressure loss of the fluid due to friction occurs when it flows through the combustion chamber. This means that the fluid in the combustion chamber 112 has a lower total pressure than the fluid in the fluid supply device 110 or the prechamber 111.
  • two injectors 125, 125 'are arranged according to the invention in addition to the recirculation openings 120, 120' in the embodiment of the invention shown in FIG .
  • These injectors 125, 125 'are arranged such that they open into the fluid supply device 110 in a region downstream of the recirculation openings 120, 120'.
  • the injectors 125, 125 'are designed here as nozzles with a tapering flow cross section. In the embodiment of the invention shown in Figure 1, two injectors 125, 125 'are arranged.
  • the injectors 125, 125 ' are preferably fed from the same fluid reservoir as the fluid supply device 110.
  • the feeding of the injectors 125, 125' is not shown in FIG. 1.
  • a supply from a reservoir can be implemented in a simple manner by means of a bypass channel.
  • This bypass duct branches off at the outlet of the compressor preceding the combustion chamber. While part of the fluid coming from the compressor flows through the fluid supply device 110 with a relatively large total pressure loss, the remaining part of the fluid coming from the compressor is supplied to the combustion chamber via the bypass channel.
  • the fluid 126 supplied to the combustion chamber flow by means of the injectors 125, 125 ′ leads to an increase in the mean total pressure of the flow downstream of the injection and thus to a sufficient pressure drop across the burner or burners.
  • the stable operating range of the combustion chamber in the embodiment with the recirculation device according to the invention is expanded by the arrangement of the injectors 125, 125 '.
  • the effectiveness of the injectors 125, 125 ' is heavily dependent on the density ratio of the injected fluid to the surrounding fluid.
  • the surrounding fluid that is to say the fluid emerging from the recirculation openings 120, 120 ′ mixed with the fluid supplied in the fluid supply device 110
  • the effectiveness of the injectors decreases. This leads to the fact that the recirculation openings 120, 120 'in combination with the injection via the injectors 125, 125' constitute an inherently stable control loop.
  • FIG. 2 shows a second embodiment of the invention in a section through a further combustion chamber.
  • the combustion chamber shown here is constructed similarly to the combustion chamber shown in FIG. 1. This similarity in the design of the combustion chambers according to FIGS. 1 and 2 does not limit the general scope of the invention in connection with other types of combustion chamber.
  • the combustion chamber essentially consists of a fluid supply device 210, a pre-chamber 211, a pre-mixing device 214 and a combustion chamber 212 with a front panel delimiting the combustion chamber.
  • the mode of operation corresponds to the mode of operation of the combustion chamber shown in FIG. 1.
  • the combustion chamber shown in FIG. 2 has recirculation openings 220, 220 '.
  • the recirculation openings 220, 220 ′ are embodied here in the form of nozzles, the nozzles being at a 90 ° angle and opening into the fluid supply device 210.
  • the combustion chamber shown in FIG. 2 has damping volumes 230, 230 'arranged on the hub side and on the housing side.
  • the damping volumes 230, 230 ' which advantageously each extend over the entire circumference of the combustion chamber, are here arranged on the outer sides of the combustion chamber in such a way that the fluid emerging from the recirculation openings 220, 220' at least partially flows into the damping volumes 230, 230 ' .
  • the damping volumes 230, 230 ′ are each connected to the fluid supply device 210 by means of an opening. Depending on the pressure conditions, fluid can thus flow in and out of the fluid supply device 210 into the damping volumes 230, 230 ′ and in the opposite direction.
  • the damping volumes 230, 230 ' will have approximately the same static pressure as in the fluid supply device 210.
  • the structural design of the fluid supply device 210 is moreover advantageously selected such that a balanced static pressure is obtained at base load and a slightly lower static pressure at full load Sets pressure in the damping volumes 230, 230 'in comparison to the fluid in the combustion chamber 212.
  • the damping volumes 230, 230 ' are each designed approximately with the same volume as the primary zone of the combustion chamber. Fluid flowing out of the combustion chamber 212 as a result of acoustic and / or thermoacoustic vibrations flows at least partially into the damping volumes 230, 230 '.
  • This proportion of cooler fluid ensures a lower average temperature of the fluid in the damping volumes 230, 230 'compared to the temperature of the fluid in the combustion chamber 212.
  • the fluid in the damping volumes 230, 230' is in turn successively introduced into the flow through the opening of the fluid supply device 210.
  • FIGS. 3, 4 and 5 The results of a computational simulation of a combustion chamber corresponding to FIG. 2 are shown in FIGS. 3, 4 and 5.
  • a total pressure of 16 bar at the end of the fluid supply device, a fluid density of 7.7 kg / m 3 at the end of the fluid supply device, and a density of the air blown in via the injectors of 8.3 kg / were used as input parameters for the simulation.
  • m 3 and a diffuser efficiency of 0.7 are used.
  • the channel widening of the fluid supply device in front of the prechamber is considered to be the diffuser.
  • the results shown in the figures apply to optimized cross sections of the recirculation openings and the injectors.
  • FIG. 1 The results shown in the figures apply to optimized cross sections of the recirculation openings and the injectors.
  • FIG 3 shows the pressure loss of the fluid supply device arranged for cooling the combustion chamber wall and the combustion chamber above the pressure loss of the entire combustion chamber. It should be taken into account here that, according to the specifications, the fluid supplied via the injectors compensates for the pressure loss of the burners. This pressure loss of the burner as the pressure loss between the prechamber and the recirculation openings remains unchangeable over the entire abscissa area. In contrast, the pressure loss of the fluid supply device increases continuously and at the same time determines the pressure loss across the entire combustion chamber.
  • the associated percentage fluid mass flow which is supplied to the combustion chamber via the fluid supply device, is plotted against the pressure loss of the combustion chamber. In the area of low pressure loss in the combustion chamber, the percentage fluid mass flow is also very low.
  • FIG. 5 shows the ratio of the cross-sectional area of the injectors (A2) assigned to the respective pressure loss of the combustion chamber to the total cross-sectional area (A1 + A2) of the injectors and the fluid supply device.
  • the cross-sectional area of the injectors thus decreases with an increasing pressure loss in the combustion chamber.
  • the low fluid mass flow shown in FIG. 4 through the fluid supply device is supplied to the combustion chamber in some cases, especially when used for Cooling of the combustion chamber wall, not sufficient. In such cases, the increase of the fluid mass flow, the invention is advantageously carried out with a further feature become.
  • a lower mass flow must the injectors 325, 325 'are supplied. This leads to a larger fluid mass flow through the fluid delivery device 310 compared to the embodiments of the invention corresponding to Figures 1 and 2.
  • the combustion chamber shown is again as Premix combustion chamber with a fluid supply device 310, a pre-chamber 311, one Premixing device 314 and a combustion chamber 312 with a front end Front panel executed.
  • the combustion chamber also has two in the front Recirculation openings 320, 320 'arranged in part of the combustion chamber.
  • the Recirculation openings 320, 320 ' are designed here so that at least part of the fluid exiting the combustion chamber flows into a damping volume 330, 330 'and is forwarded from there into the fluid supply device 310.
  • the Fluid supply device 310 in the region of the opening 335 of the damping volumes 330, 330 ', or the recirculation openings 320, 320', each as a Venturi nozzle 340, 340 ' executed.
  • the fluid mass flow that goes through the injectors 325, 325 'is fed to the combustion chamber, can thus have smaller flow cross sections of the injectors can be reduced. Accordingly, the mass flow, which is the Combustion chamber is supplied by the fluid supply device 310 and for cooling the Contributes to the combustion chamber wall, increases.
  • FIG. 7 shows a further embodiment of the invention.
  • the combustion chamber shown is there from a fluid supply device 410, a pre-chamber 411, a premixing device 414 and a combustion chamber 412, which is closed at the front by means of a front panel.
  • the Recirculation openings 420, 420 'designed according to the invention are on the front panel arranged. At least part of the fluid 421 emerging from the combustion chamber 412 flows into the damping volumes 430, 430 ', which adjoin the combustion chamber 412 on the end face are arranged and extend spatially into the prechamber 411.
  • the Flow channels between the damping volumes 430, 430 'and the Combustion chamber outer wall, which are to be regarded as part of the fluid supply device 410, are expediently designed here as Venturi nozzles.
  • the narrowest cross sections 441, 441 'of Venturi nozzles are located slightly downstream of the orifices 435, 435 'of the Damping volumes 430, 430 ', or the recirculation openings 420, 420', in the fluid supply device 410.
  • the each according to the narrowest cross sections 441, 441 ' of the Venturi nozzles adjoining diffusers 442, 442 'of the Venturi nozzles are respectively executed in two parts.
  • a first part of the diffusers lies in the area between the narrowest Cross section 441, 441 'of the Venturi nozzles and injectors 425, 425'.
  • the second part of the Diffusers 442, 442 ' are each arranged downstream of the injectors 425, 425'.
  • the mode of action the embodiment of the invention shown in FIG. 7 is equivalent to the mode of operation of the device shown in FIG Figure 6 illustrated embodiment of the invention. Differences between the two versions of the Invention arise in particular in the designs and thus the Combustion chamber dimensions.
  • FIGS. 8, 9 and 10 The results of a computational simulation of an embodiment of the invention corresponding to FIG. 7 are shown in FIGS. 8, 9 and 10.
  • a total pressure of 16 bar at the end of the fluid supply device, a fluid density of 8 kg / m 3 at the end of the fluid supply device, and a density of the air blown in via the injectors of 8.3 kg / m 3 were used as input parameters for the simulation , a diffuser efficiency of the first part of the diffuser of 0.8 and the second part of the diffuser of 0.5, a flow velocity in the venturi nozzles of 87 m / s and an increase in total pressure of 3 per thousand as a result of the injection by means of the injectors placed.
  • FIG. 8 shows in the same representation as FIG.
  • FIG. 9 shows the percentage mass flow that is supplied to the combustion chamber as cooling air through the fluid supply device.
  • FIG. 10 shows the ratio of the cross-sectional areas of the injectors (A2) assigned to the respective pressure loss to the total cross-sectional area (A1 + A2) of the injectors and the fluid supply device.
  • Figure 11 shows an embodiment of the invention, which is also particularly suitable for the optimal volume of the damping volume 530 for effective acoustic damping and / or thermoacoustic vibrations depending on the combustion chamber and the to determine the respective operating point.
  • the combustion chamber shown here consists of a fluid supply device 510, a pre-chamber 511, a premixing device 514 and a combustion chamber 512, which is separated from the prechamber 511 by a front panel 515 is delimited.
  • the fluid delivery device 510 is not here as in the previous ones Representations for cooling the combustion chamber wall adjacent to the combustion chamber arranged. For damping acoustic and / or thermoacoustic vibrations there was also a recirculation opening 520 in the combustion chamber wall arranged.
  • the recirculation opening 520 opens into a damping volume 530 Volume of the damping volume 530 can be via a sliding boundary wall to be changed. As a result, the damping power over the frequency range vary.
  • the fluid 521 entering the damping volume 530 from the combustion chamber 512 recirculates back into the combustion chamber 512 via the recirculation opening 520.
EP98810901A 1998-09-10 1998-09-10 Amortissement des vibrations dans des combusteurs Expired - Lifetime EP0985882B1 (fr)

Priority Applications (3)

Application Number Priority Date Filing Date Title
DE59810347T DE59810347D1 (de) 1998-09-10 1998-09-10 Schwingungsdämpfung in Brennkammern
EP98810901A EP0985882B1 (fr) 1998-09-10 1998-09-10 Amortissement des vibrations dans des combusteurs
US09/392,791 US6430933B1 (en) 1998-09-10 1999-09-09 Oscillation attenuation in combustors

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
EP98810901A EP0985882B1 (fr) 1998-09-10 1998-09-10 Amortissement des vibrations dans des combusteurs

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EP0985882A1 true EP0985882A1 (fr) 2000-03-15
EP0985882B1 EP0985882B1 (fr) 2003-12-03

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WO2001027534A1 (fr) * 1999-10-12 2001-04-19 Alm Development, Inc. Chambre de combustion et procede de combustion de carburant
DE10019890A1 (de) * 2000-04-20 2001-10-25 Webasto Thermosysteme Gmbh Brenner mit Flammrohr
US6973790B2 (en) 2000-12-06 2005-12-13 Mitsubishi Heavy Industries, Ltd. Gas turbine combustor, gas turbine, and jet engine
US7331182B2 (en) 2002-01-16 2008-02-19 Alstom Technology Ltd Combustion chamber for a gas turbine
EP2383514A1 (fr) * 2010-04-28 2011-11-02 Siemens Aktiengesellschaft Système de brûleur et procédé d'amortissement d'un tel système de brûleur
US8689561B2 (en) 2009-09-13 2014-04-08 Donald W. Kendrick Vortex premixer for combustion apparatus
EP2957835A1 (fr) * 2014-06-18 2015-12-23 Alstom Technology Ltd Procédé de recirculation des gaz d'échappement provenant d'une chambre de combustion d'un brûleur d'une turbine à gaz et turbine à gaz pour l'exécution de ce procédé

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DE10257245A1 (de) * 2002-12-07 2004-07-15 Alstom Technology Ltd Verfahren und Vorrichtung zur Beeinflussung thermoakustischer Schwingungen in Verbrennungssystemen
DE10257244A1 (de) * 2002-12-07 2004-07-15 Alstom Technology Ltd Verfahren und Vorrichtung zur Beeinflussung thermoakustischer Schwingungen in Verbrennungssystemen
US7302802B2 (en) * 2003-10-14 2007-12-04 Pratt & Whitney Canada Corp. Aerodynamic trip for a combustion system
US7464552B2 (en) * 2004-07-02 2008-12-16 Siemens Energy, Inc. Acoustically stiffened gas-turbine fuel nozzle
US8024934B2 (en) * 2005-08-22 2011-09-27 Solar Turbines Inc. System and method for attenuating combustion oscillations in a gas turbine engine
GB0610800D0 (en) * 2006-06-01 2006-07-12 Rolls Royce Plc Combustion chamber for a gas turbine engine
US8127546B2 (en) * 2007-05-31 2012-03-06 Solar Turbines Inc. Turbine engine fuel injector with helmholtz resonators
US8028512B2 (en) 2007-11-28 2011-10-04 Solar Turbines Inc. Active combustion control for a turbine engine
CH699309A1 (de) * 2008-08-14 2010-02-15 Alstom Technology Ltd Thermische maschine mit luftgekühlter, ringförmiger brennkammer.
US9759424B2 (en) * 2008-10-29 2017-09-12 United Technologies Corporation Systems and methods involving reduced thermo-acoustic coupling of gas turbine engine augmentors
US20100236245A1 (en) * 2009-03-19 2010-09-23 Johnson Clifford E Gas Turbine Combustion System
US9127837B2 (en) * 2010-06-22 2015-09-08 Carrier Corporation Low pressure drop, low NOx, induced draft gas heaters
EP2559945A1 (fr) * 2011-08-17 2013-02-20 Siemens Aktiengesellschaft Agencement de combustion et turbine dotée d'amortissement
US20140182304A1 (en) * 2012-12-28 2014-07-03 Exxonmobil Upstream Research Company System and method for a turbine combustor
WO2014071123A2 (fr) * 2012-11-02 2014-05-08 General Electric Company Système et procédé pour foyer de turbine
US9803865B2 (en) 2012-12-28 2017-10-31 General Electric Company System and method for a turbine combustor
US9631815B2 (en) * 2012-12-28 2017-04-25 General Electric Company System and method for a turbine combustor
WO2014071120A2 (fr) * 2012-11-02 2014-05-08 General Electric Company Système et procédé pour foyer de turbine
JP6327826B2 (ja) * 2013-10-11 2018-05-23 川崎重工業株式会社 ガスタービンの燃料噴射装置
EP3026346A1 (fr) * 2014-11-25 2016-06-01 Alstom Technology Ltd Chemise de chambre de combustion
EP3026347A1 (fr) * 2014-11-25 2016-06-01 Alstom Technology Ltd Brûleur a corps non profilé annulaire
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WO2001027534A1 (fr) * 1999-10-12 2001-04-19 Alm Development, Inc. Chambre de combustion et procede de combustion de carburant
DE10019890A1 (de) * 2000-04-20 2001-10-25 Webasto Thermosysteme Gmbh Brenner mit Flammrohr
DE10019890C2 (de) * 2000-04-20 2003-05-22 Webasto Thermosysteme Gmbh Brenner mit Flammrohr
US6973790B2 (en) 2000-12-06 2005-12-13 Mitsubishi Heavy Industries, Ltd. Gas turbine combustor, gas turbine, and jet engine
US7331182B2 (en) 2002-01-16 2008-02-19 Alstom Technology Ltd Combustion chamber for a gas turbine
US8689561B2 (en) 2009-09-13 2014-04-08 Donald W. Kendrick Vortex premixer for combustion apparatus
EP2383514A1 (fr) * 2010-04-28 2011-11-02 Siemens Aktiengesellschaft Système de brûleur et procédé d'amortissement d'un tel système de brûleur
WO2011134713A1 (fr) * 2010-04-28 2011-11-03 Siemens Aktiengesellschaft Système de combustion pour amortir un système de combustion
EP2957835A1 (fr) * 2014-06-18 2015-12-23 Alstom Technology Ltd Procédé de recirculation des gaz d'échappement provenant d'une chambre de combustion d'un brûleur d'une turbine à gaz et turbine à gaz pour l'exécution de ce procédé
CN105276616A (zh) * 2014-06-18 2016-01-27 阿尔斯通技术有限公司 用于使排气再循环的方法和用于执行所述方法的燃气涡轮

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EP0985882B1 (fr) 2003-12-03
DE59810347D1 (de) 2004-01-15

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