EP0990851B1 - Brennkammer für eine Gasturbine - Google Patents
Brennkammer für eine Gasturbine Download PDFInfo
- Publication number
- EP0990851B1 EP0990851B1 EP98810983A EP98810983A EP0990851B1 EP 0990851 B1 EP0990851 B1 EP 0990851B1 EP 98810983 A EP98810983 A EP 98810983A EP 98810983 A EP98810983 A EP 98810983A EP 0990851 B1 EP0990851 B1 EP 0990851B1
- Authority
- EP
- European Patent Office
- Prior art keywords
- perforated plate
- openings
- combustion chamber
- cooling air
- perforated
- 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 - Lifetime
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Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23R—GENERATING COMBUSTION PRODUCTS OF HIGH PRESSURE OR HIGH VELOCITY, e.g. GAS-TURBINE COMBUSTION CHAMBERS
- F23R3/00—Continuous combustion chambers using liquid or gaseous fuel
- F23R3/02—Continuous combustion chambers using liquid or gaseous fuel characterised by the air-flow or gas-flow configuration
- F23R3/04—Air inlet arrangements
- F23R3/10—Air inlet arrangements for primary air
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23M—CASINGS, 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
- F23M20/00—Details of combustion chambers, not otherwise provided for, e.g. means for storing heat from flames
- F23M20/005—Noise absorbing means
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23R—GENERATING COMBUSTION PRODUCTS OF HIGH PRESSURE OR HIGH VELOCITY, e.g. GAS-TURBINE COMBUSTION CHAMBERS
- F23R3/00—Continuous combustion chambers using liquid or gaseous fuel
- F23R3/002—Wall structures
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
- F05B—INDEXING SCHEME RELATING TO WIND, SPRING, WEIGHT, INERTIA OR LIKE MOTORS, TO MACHINES OR ENGINES FOR LIQUIDS COVERED BY SUBCLASSES F03B, F03D AND F03G
- F05B2260/00—Function
- F05B2260/96—Preventing, counteracting or reducing vibration or noise
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23R—GENERATING COMBUSTION PRODUCTS OF HIGH PRESSURE OR HIGH VELOCITY, e.g. GAS-TURBINE COMBUSTION CHAMBERS
- F23R2900/00—Special features of, or arrangements for continuous combustion chambers; Combustion processes therefor
- F23R2900/00014—Reducing thermo-acoustic vibrations by passive means, e.g. by Helmholtz resonators
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23R—GENERATING COMBUSTION PRODUCTS OF HIGH PRESSURE OR HIGH VELOCITY, e.g. GAS-TURBINE COMBUSTION CHAMBERS
- F23R2900/00—Special features of, or arrangements for continuous combustion chambers; Combustion processes therefor
- F23R2900/03341—Sequential combustion chambers or burners
Definitions
- the present invention relates to the field of gas turbines. It affects a combustion chamber for a gas turbine, in which combustion chamber the hot combustion gases a combustion zone are enclosed by inner walls, which by cooling air, which by outside of the inner walls by a The outer wall of the combustion chamber and the inner walls formed cooling air channels is introduced, cooled.
- Such a combustion chamber is in the form of a secondary combustion chamber e.g. from the Document EP-A1 0 669 500 of the applicant is known.
- Gas turbines can cause pressure vibrations during operation under certain conditions or acoustic vibrations that occur in terms of frequency Range of several kHz, e.g. are in the range of 2-6 kHz. Such vibrations prove to be disruptive to the operation and are therefore undesirable.
- damping or suppressing such vibrations in providing fluidic means in the combustion chamber which influence the flow of hot gases in such a way that the acoustic Vibrations are not excited or only to a small extent.
- Helmholtz resonators on the combustion chamber to attach, which couple to the vibrations as damping elements and dampen the vibrations or make them disappear completely.
- a gas turbine combustor is described in US Pat. No. 5,644,918, with the leading within the cooling air surrounding the combustion chamber Double jacket and on the front of the combustion chamber in the area of the burner by pulling in additional dividing walls Helmholtz resonators 48 and 56 are formed, the constrictions 50 and 58 in connection with the combustion chamber stand, but are otherwise completely completed, so that a Flow of cooling air through the resonator rooms does not take place.
- European publication EP-A1-0 576 717 discloses a gas turbine combustor.
- the flame tube is located away from the combustion chamber Side exposed to an air flow supplied by the gas turbine compressor.
- the flame tube is essentially composed of wall parts, the combustion chamber outer wall parts facing away from each have a plurality of inlet openings distributed over the circumference have, introduced via the cooling air into an intermediate space arranged in the flame tube becomes. From the intermediate space, the cooling air is passed through outlet bores into the combustion chamber facing inner wall parts introduced into the combustion chamber.
- the space between the wall parts is on to form a Helmholtz resonator large, closed additional volume coupled, with the inlet openings in the outer wall parts as feed pipes and the outlet bores as damping pipes of the Helmholtz resonator, are formed.
- EP-A1-0 971 172 discloses a gas turbine.
- this combustion chamber in which the hot combustion gases of a combustion zone are enclosed by inner walls, which is cooled by cooling air brought in outside the inner walls a simultaneous efficient acoustic damping and cooling achieved that at least in a partial area on the outside of the inner walls, a distance from the inner walls, perforated plate arranged essentially parallel to the inner walls which, together with the associated inner wall, is a closed damping volume forms that the inner walls in the region of the damping volume a plurality of distributed first openings through which the damping volume with the combustion zone of the combustion chamber communicates that the perforated plate is a Has a plurality of distributed second openings through which cooling air from flows into the outside of the damping volume and in the manner of an impingement cooling between the first openings meets the opposite outside of the inner wall, and that the Distance between the perforated plate and the inner wall and the geometric dimensions of the first openings are selected so that the first openings together with the damping volume form a plurality
- the task is thereby in a combustion chamber of the type mentioned solved that at least in a partial area of the inner walls of the inner wall at least two perforated plates arranged essentially parallel to one another is formed that a first perforated plate borders directly on the cooling air channels and is provided with a plurality of first openings through which cooling air from the cooling air channels into a first intermediate volume lying behind the first perforated plate flows that behind the first perforated plate, towards the combustion zone, a further perforated plate is arranged, which with a plurality of further openings is provided that the distance between the first perforated plate and the other perforated plate and the geometric dimensions of the others Openings and are selected so that the openings together with between the perforated plates existing intermediate volumes a plurality of one another connected Helmholtz resonators and as a silencer for in acoustic vibrations arising in the combustion chamber act, and that in addition there are other agents which have a sound-absorbing effect.
- the essence of the invention is therefore that the combination of Helmholtz
- a first preferred embodiment of the invention is characterized by that at least in a partial area of the inner walls, the inner wall of three, in perforated plates arranged substantially parallel to each other is formed that a first perforated plate directly adjoins the cooling air ducts and with a plurality is provided by first openings through which cooling air from the cooling air channels into a first intermediate volume lying behind the first perforated plate flows, which on the side facing the cooling air ducts from the first Perforated plate and on the opposite side of a second perforated plate is limited, which second perforated plate with a plurality of second openings is provided that on the side facing away from the first intermediate volume of the second perforated plate, a third perforated plate is arranged, which has a plurality is provided by third openings, and which to the combustion zone borders, and that at least one of the perforated plates additionally sound-absorbing acts.
- the essence of the embodiment is that a of the three perforated plates by appropriate hole design, or by appropriate Contraction ratio, the most possible reflection-free sound transmission has, and that the combination and the geometric design of two further perforated plates a plurality of interconnected Helmholtz resonators creates a phase shift.
- the whole Absorption system flushed by cooling air, making the resonators thermal and frequency stabilized. The additional effort to create of the absorption system - if there is effusion cooling the large openings in the inner wall already exist - only from attaching two more perforated plates.
- a second preferred embodiment of the combustion chamber according to the invention is characterized in that the contraction ratio, defined as the Ratio between the area of the opening and that towards the combustion zone surface in front, for the second or third openings in the is essentially the same as the largest Mach number that occurs in the combustion chamber, which is defined as the ratio of the source velocity and the Speed of sound, and that the perforated plate provided with such openings has a sound-absorbing effect.
- the contraction ratio defined as the Ratio between the area of the opening and that towards the combustion zone surface in front
- the second or third openings in the is essentially the same as the largest Mach number that occurs in the combustion chamber, which is defined as the ratio of the source velocity and the Speed of sound, and that the perforated plate provided with such openings has a sound-absorbing effect.
- a second preferred embodiment of the combustion chamber according to the invention is characterized in that the distance between the first perforated plate and of the second perforated plate and the geometric dimensions of the second openings be chosen such that the second openings in combination with the first space arranged between the first and the second perforated plate Helmholtz resonators result in their resonance frequency essentially in the area of acoustic vibrations occurring in the combustion chamber lies, and that further preferably the third perforated plate is designed to be sound-absorbing is.
- the third perforated plate leads to anechoic transmission of the Noise and the Helmholtz resonators behind it in the direction of sound propagation push its phase.
- the second perforated plate has a thickness in the range from 0.1 to 1 cm, in particular preferably from 0.6 cm, the area ratio of the acoustically relevant Partial areas of the first intermediate volume and the areas of the second openings are in the range from 5 to 10, particularly preferably from 8, the distance between the first of the second perforated plate is 0.1 to 1 cm, particularly preferred 0.6 cm, the product of the contraction ratio of the third openings and the largest Mach number ranges from 1 to 0.5, and the area ratio of the acoustic relevant areas in the combustion chamber and the acoustically relevant areas the first intermediate volume is in a range from 1 to 2.
- Another preferred embodiment of the combustion chamber according to the invention is characterized in that the distance between the first perforated plate and of the third perforated plate and the geometric dimensions of the third openings be chosen such that the third openings in combination with the between the first and the third perforated plate arranged Helmholtz resonators result, whose resonance frequency is essentially in the range the acoustic vibrations occurring in the combustion chamber, and that the second perforated plate is preferably also sound-absorbing.
- the sound-absorbing arrangement can be designed acoustically, if, according to a further embodiment, the second and the third Perforated plate with even and concentric arrangement of the holes in the two perforated plates can be joined directly and without spacing, or that the two perforated plates can even be covered by a single perforated plate holes drilled on both sides with different diameters become.
- a secondary combustion chamber is shown in a simplified longitudinal section, which is known from EP-A1 0 669 500, and which is preferred for implementation the invention is suitable.
- the combustion chamber 10 includes a combustion zone 23, which of an inner wall extending in the axial direction 12 and a radial inner wall 17 is limited.
- the inflow zone 20 is delimited by an inner wall 15. Protrudes into the inflow zone 20 a fuel lance 18 from the side, a nozzle at the front end 19 for fuel injection.
- the inner walls 12, 15 and 17 are from an outer wall 11 extending in the axial direction.
- a cooling air duct 14 remains free through the inner wall 12 and the outer wall 11 which cooling air against the flow direction of the hot gases in between the inner wall 15 and the outer wall 11 formed rear cooling air duct 16 streams.
- the inner wall 12 is convectively cooled by the cooling air.
- the cooling air flows from the rear cooling air duct 16 through openings 21 in the inner wall 15 in the inflow zone 20, and through further openings 22 in the radial Inner wall 17 into the combustion zone 23, thereby causing effusion cooling.
- a Helmholtz resonator arrangement in combination with a sound-absorbing third perforated plate 29 are integrated, which at the same time effective cooling of the arrangement guaranteed.
- a first perforated plate 24 is arranged in parallel at a distance (L in FIG. 4), which together with the actual radial inner wall, which is a forms second perforated plate 17a, includes a first (annular) intermediate volume 26.
- the second perforated plate 17a has a plurality of more or less regularly distributed openings 27a, which are identical to the openings 22 for the effusion cooling in the combustion chamber according to FIG. 1 can be, but also deviating can have geometric dimensions.
- the as through holes with a diameter a and a length I (Fig. 4) formed openings 27a each act individually as a damping tube of a Helmholtz partial resonator, that of the respective opening 27a and the partial volume behind it first intermediate volume 26 is formed.
- the first intermediate volume 26 in total and the entirety of the openings 27a can be used as individual Helmholtz resonators understand, the individual damping volumes with each other to first intermediate volume 26 are connected.
- the first perforated plate 24 has in addition to the limitation of the first intermediate volume two other important tasks. Those provided in the first perforated plate 24 Openings 25 let cooling air from the rear cooling air duct 16 into the first intermediate volume 26 flow in.
- the incoming cooling air cools the one hand Helmholtz arrangement. This is the geometry and thus the Damping frequency of the arrangement kept stable.
- the openings 25 offset relative to the second openings 27a or arranged "on gap".
- the diameter of the openings 25 is compared to the diameter a small (Fig. 4). This ensures that the cooling air flowing through one suffers sufficient pressure drop.
- a third perforated plate 29 arranged in parallel, which together with the second perforated plate 17a a second (ring-shaped) intermediate volume 30 includes.
- the third perforated plate 29 has a plurality of distributed ones Openings 28 on. These openings 28 are preferably designed such that the third perforated plate 29 the sound generated in the combustion zone 23 transmits echo-free, i.e. that no sound is reflected and therefore this third Perforated plate has a sound-absorbing effect.
- the second intermediate volume 30 and the third perforated plate are the by the first intermediate volume and the Cooling air flowing through second openings 27a and cooled accordingly.
- FIG 3 shows schematically the structure of the embodiment shown in Figure 2 the invention again.
- the incoming from the combustion zone 23 Sound 31 first passes through the openings 28 of the third perforated plate in an echo-free manner 29 into the second intermediate volume 30. Then the sound hits that from the first 24 and the second 17a perforated plate with the Helmholtz resonators formed with the openings 27a, which push the phase of the sound waves. Flows at the same time by the arrangement in the opposite direction to the sound of the cooling air flow 22 after he through the openings 25 in the first perforated plate 24 into the first intermediate volume 26 has arrived.
- a schematic representation of the arrangement, which can be used to calculate its Properties is particularly suitable, together with the specification of the dimensions shown in Figure 4.
- the main characteristics of this series of elements can be easily calculated by calculating the transformation behavior the Riemannin variants for each element and subsequent determine sequential sequence of transformations.
- particularly important property of the sound absorbing perforated plate applies that the transmission of the sound absorbing perforated plate for flow lower Mach numbers then echo-free, i.e. is reflection-free if the contraction ratio, defined as the ratio of the area of the aperture or opening b to the area B in front of the aperture (b / B) is essentially the same as the largest in the Mach number that occurs in the chamber.
- the resonance frequency of the resonator arrangement or the partial resonators is in the essentially by the area A, the thickness I of the second perforated plate 17a or Length of the openings 27a, the diameter of the openings 27a and spacing L of the plates determined.
- the openings 27a are as through holes with a length I of a few millimeters and a diameter a of a few millimeters.
- the distance L between the first 24 and the second 17a perforated plate is a few millimeters, and the ratio of area A to hole area a is in the range from 5 to 10.
- Fig. 5a The damping behavior of the arrangement for the values from the table from Helmholtz resonators and sound-absorbing perforated plate 29 is in Fig. 5a) reproduced.
- 5 shows the squared reflection coefficient in each case (reflection coefficient squared) over the frequency in Hz.
- Fig. 5a One can see Fig. 5a), that for the above values in the whole range from 2 to 6 kHz significant absorption takes place, and that resonant absorption occurs at 4720 Hz.
- Very strong Absorption is in the range from 3.5 to 5.5 kHz, where more than 75% of the acoustic Power to be absorbed.
- FIG 6 Another embodiment of an embodiment of the invention is shown in FIG 6 shown.
- the sound-absorbing sheet is in the actual damping volume of the Helmholtz resonators.
- the Helmholtz resonators are in in this case from a first perforated plate facing the rear cooling air duct 16 24 and a third perforated plate directly adjacent to the combustion zone 23 17b formed.
- the first perforated plate 24 in turn has openings 25, through which cooling air 22 flows into the arrangement.
- the third perforated plate 17b has Openings 27b, which serve as damping tubes of the Helmholtz resonators.
- the damping volume of the Helmholtz resonators exposes itself in this case the two intermediate volumes 32 and 35 together, which by the between the first 24 and the third 17b perforated plate retracted second perforated plate 34 be formed.
- the second perforated plate 34 is provided with openings 33 which are designed such that this second perforated plate 34 is sound-absorbing, i.e. appears anechoic. As described above, this is done by adjusting to the highest Mach number Contraction ratio.
- FIG. 7 again shows a schematic illustration of how the sound 31 from the Combustion zone 23 strikes the arrangement with internal absorber, and how the cooling air 22 through the openings 25 from the opposite side flows.
- the one used to calculate the main characteristic properties of a is analogous to FIG. 4 given in Figure 8 along with the dimensions.
- the resonance frequency of the In this case, the resonator arrangement or the partial resonators essentially becomes by the area A, the thickness I1 of the third perforated plate 17b or the length of the openings 27b, the diameter of the openings 27b and spacing L1 of the plates.
- the openings 27b are the openings 27b as through holes with a length I1 of a few Millimeters and a diameter of a few millimeters.
- the distance L1 between the first 24 and the third 17b perforated plate is a few Millimeters, and the ratio of area A to hole area a is in the range from 5 to 10.
- Fig. 9a The damping behavior of the arrangement for the values from the table from Helmholtz resonators and internal sound-absorbing perforated plate 34 is shown in Fig. 9a).
- Fig. 9 again shows the squared Reflection coefficient squared over frequency in Hz. It can be seen in FIG. 9 a) that for the above values in the entire range from 2 to 6 kHz significant absorption takes place, and that at 3880 Hz resonant absorption occurs. One has very strong absorption in the range from 2.9 to 5.2 kHz, where more than 75% of the acoustic power is consumed.
- a perforated plate 37 is for an arrangement with internal absorber shown in Figure 10.
- the perforated plate 37 has openings of different diameters from the two sides, wherein the second stage part 39 facing the combustion zone 23 to the damping tubes 27b from FIG.
- first step part 38 ensures anechoic transmission and corresponds to the openings 33 from FIG. 6. In this way you have the advantage of only having to provide two perforated plates, which greatly simplifies cooling and construction, and still one efficient combined arrangement of Helmholtz resonators and sound absorbers to have.
- All of the above exemplary embodiments are distinguished in that they are based on can be easily installed in an existing combustion chamber.
- the exemplary embodiments described here become the former radial Inner wall 17 once as the second 17a and once as the third 17b perforated plate three-part arrangement used.
- the former radial Inner wall 17 but take over the task of each of the three perforated plates or else that of the perforated plate 37 with stepped openings.
- Retrofitting can be done in one way or another.
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- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Soundproofing, Sound Blocking, And Sound Damping (AREA)
Description
- Fig. 1
- im vereinfachten Längsschnitt eine Sekundärbrennkammer, wie sie aus dem Stand der Technik, insbesondere der EP-A1 0 669 500, bekannt ist;
- Fig. 2
- einen vergrösserten Ausschnitt der Brennkammer nach Fig. 1 im Bereich des stufenartigen Übergangs zwischen Zuströmzone und Verbrennungszone mit einer integrierten Helmholtzresonator-Anordnung und einem extern angeordneten Dämpfungsblech gemäss einem bevorzugten Ausführungsbeispiel der Erfindung;
- Fig. 3
- eine schematische Darstellung eines Schnittes der Anordnung nach Figur 2;
- Fig. 4
- eine vereinfachte kleinste Berechnungseinheit für eine Anordnung gemäss Fig. 2 mit externem Dämpfungsblech;
- Fig. 5
- die quadrierten Reflexionskoeffizienten als Funktion der Frequenz in verschiedenen Anordnungen mir externem Dämpfungsblech;
- Fig. 6
- einen vergrösserten Ausschnitt der Brennkammer nach Fig. 1 im Bereich des stufenartigen Übergangs zwischen Zuströmzone und Verbrennungszone mit einer integrierten Helmholtzresonator-Anordnung und einem intern angeordneten Dämpfungsblech gemäss einem bevorzugten Ausführungsbeispiel der Erfindung;
- Fig. 7
- eine schematische Darstellung eines Schnittes der Anordnung nach Figur 6;
- Fig. 8
- eine vereinfachte kleinste Berechnungseinheit für eine Anordnung gemäss Fig. 6 mit internem Dämpfungsblech;
- Fig. 9
- die quadrierten Reflexionskoeffizienten als Funktion der Frequenz in verschiedenen Anordnungen mir internem Dämpfungsblech; und
- Fig. 10
- einen Schnitt durch ein Lochblech, welches das zweite und das dritte Lochblech ersetzt für den Fall eines internen Dämpfungsblechs.
Eingangswerte | ||
Temperatur der Luft | 770 | K |
Bohrungslänge I | 6 | mm |
Plattenabstand L | 6 | mm |
Plattenabstand X | 6 | mm |
Flächenverhältnis A/a | 8 | |
Flächenverhältnis B/A | 1 | |
Produkt aus Machzahl und inversem Kontraktionsverhältnis | 1 | |
Massenfluss der Kühlluft | 3.88 | kg/(s*m^2) |
Druck im Brenner | 16.6 | bar |
Ausgangswerte | ||
Flussgeschwindigkeit in den Öffnungen 27a | 4.13 | m/s |
Inverses Kontraktionsverhältnis | 32.81 | |
Flussgeschwindigkeit durch die dritte Lochplatte 29 | 16.94 | m/s |
Ausgangswerte | ||
Inverses Kontraktionsverhältnis | 23.21 | |
Flussgeschwindigkeit durch die dritte Lochplatte 29 | 11.98 | m/s |
Eingangswerte | ||
Temperatur der Luft | 770 | K |
Bohrungslänge I1 | 6 | mm |
Plattenabstand L1 | 8 | mm |
Plattenabstand Y | 3 | mm |
Flächenverhältnis A/a | 8 | |
Flächenverhältnis B/A | 1 | |
Produkt aus Machzahl und inversem Kontraktionsverhältnis | 2.025 | |
Massenfluss der Kühlluft | 3.88 | kg/(s*m^2) |
Druck im Brenner | 16.6 | bar |
Ausgangswerte | ||
Flussgeschwindigkeit in den Öffnungen 27b | 4.13 | m/s |
Inverses Kontraktionsverhältnis | 46.68 | |
Flussgeschwindigkeit durch die zweite Lochplatte 34 | 24.10 | m/s |
Ausgangswerte | ||
Inverses Kontraktionsverhältnis | 32.50 | |
Flussgeschwindigkeit durch die zweite Lochplatte 34 | 16.78 | m/s |
- 10
- Sekundärbrennkammer
- 11
- Aussenwand
- 12
- Innenwand (Verbrennungszone)
- 13
- Heissgasauslass
- 14
- Kühlluftkanal
- 15
- Innenwand (Zuströmzone)
- 16
- hinterer Kühlluftkanal
- 17
- radiale Innenwand
- 17a
- zweite Lochplatte
- 17b
- dritte Lochplatte
- 18
- Brennstofflanze
- 19
- Düse (Brennstofflanze)
- 20
- Zuströmzone
- 21
- Öffnung (Wand 15)
- 22
- Öffnung (Wand 17)
- 23
- Verbrennungszone
- 24
- erste Lochplatte
- 25
- erste Öffnung
- 26
- erstes Zwischenvolumen
- 27a
- zweite Öffnung
- 27b
- dritte Öffnung
- 28
- dritte Öffnung
- 29
- Lochplatte
- 30
- zweites Zwischenvolumen
- 31
- Schallwellen
- 32
- erstes Zwischenvolumen
- 33
- Öffnung in 34
- 34
- zweite Lochplatte
- 35
- zweites Zwischenvolumen
- 36
- Lochblech
- 37
- gestufte Öffnung
- 38
- erster Stufenteil
- 39
- zweiter Stufenteil
- L
- Länge des Dämpfungsvolumens
- I
- Länge des Halses
- X
- Abstand des externen perforierten Bleches von 17
- L1
- Länge des Dämpfungsvolumens
- I1
- Länge des Halses
- Y
- Abstand des internen perforierten Bleches von 17
Claims (12)
- Brennkammer (10) für eine Gasturbine, in welcher Brennkammer (10) die heissen Verbrennungsgase einer Verbrennungszone (23) durch Innenwände (12,17) umschlossen werden, welche durch Kühlluft, welche durch ausserhalb der Innenwände (12,17) durch von einer Aussenwand (11) der Brennkammer (10) und den Innenwänden (12,17) gebildete Kühlluftkanäle (14,16) herangeführt wird, gekühlt werden, wobei zumindest in einem Teilbereich der Innenwände (12,17) die Innenwand (17) aus wenigstens zwei, im wesentlichen parallel zueinander angeordneten Lochplatten (24,17a;24,17a) gebildet wird, wobei eine erste Lochplatte (24) unmittelbar an die Kühlluftkanäle (14,16) grenzt und mit einer Mehrzahl von ersten Öffnungen (25) versehen ist, durch welche Kühlluft (22) aus den Kühlluftkanälen (14,16) in ein hinter der ersten Lochplatte liegendes erstes Zwischenvolumen (26,32) strömt, wobei hinter der ersten Lochplatte (24), in Richtung der Verbrennungszone (23), eine weitere Lochplatte (17a,17b) angeordnet ist, welche mit einer Mehrzahl von weiteren Öffnungen (27a,27b) versehen ist, wobei der Abstand (L,L1) zwischen der ersten Lochplatte (24) und der weiteren Lochplatte (17a,17b) und die geometrischen Abmessungen (I,I1,a,A) der weiteren Öffnungen (27a,27b) so gewählt sind, dadurch gekennzeichnet, dass die Öffnungen (27a,27b) zusammen mit zwischen den Lochplatten (24,17a,17b) vorhandenen Zwischenvolumina (26,32,35) eine Mehrzahl von untereinander verbundenen Helmholtzresonatoren bilden und als Schalldämpfer für in der Brennkammer entstehende akustische Schwingungen (31) wirken, und
zusätzlich weitere, schallabsorbierende Mittel (29,34) vorhanden sind. - Brennkammer (10) nach Anspruch 1, dadurch gekennzeichnet, dass zumindest in einem Teilbereich der Innenwände (12,17) die Innenwand (17) aus drei, im wesentlichen parallel zueinander angeordneten Lochplatten (24,17a,29;24,34,17a) gebildet wird, wobei die erste Lochplatte (24) unmittelbar an die Kühlluftkanäle (14,16) grenzt und mit einer Mehrzahl von ersten Öffnungen (25) versehen ist, durch welche Kühlluft (22) aus den Kühlluftkanälen (14,16) in ein hinter der ersten Lochplatte liegendes erstes Zwischenvolumen (26,32) strömt, welches auf der den Kühlluftkanälen (14,16) zugewandten Seite von der ersten Lochplatte (24) und auf der gegenüberliegenden Seite von einer zweiten Lochplatte (17a,34) begrenzt ist, welche zweite Lochplatte (17a,34) mit einer Mehrzahl von zweiten Öffnungen (27a,33) versehen ist, dass auf der dem ersten Zwischenvolumen (26,32) abgewandten Seite der zweiten Lochplatte (17a,34) eine dritte Lochplatte (17b,29) angeordnet ist, welche mit einer Mehrzahl von dritten Öffnungen (27b,28) versehen ist, und welche an die Verbrennungszone (23) grenzt, und dass wenigstens eine der Lochplatten (29,34) schallabsorbierend ausgestaltet ist.
- Brennkammer (10) nach Anspruch 2, dadurch gekennzeichnet, dass das Kontraktionsverhältnis, definiert als das Verhältnis zwischen der Fläche (b) der Öffnung (28,33) und der in Richtung der Verbrennungszone (23) davor liegenden Fläche (B), für die zweiten (33) oder die dritten (28) Öffnungen im wesentlichen gleich ist wie die grösste, im Verbrennungsraum (23) auftretende, Machzahl, welche definiert ist als das Verhältnis der Quellengeschwindigkeit und der Schallgeschwindigkeit, und dass die mit solchen Öffnungen (33,28) versehene Lochplatte (29,34) schallabsorbierend wirkt.
- Brennkammer (10) nach einem der Ansprüche 2 oder 3, dadurch gekennzeichnet, dass die zweite (17a,34) und die dritte (17b,29) Lochplatte derart voneinander beabstandet sind, dass ein zweites Zwischenvolumen (30,35) gebildet wird.
- Brennkammer (10) nach einem der Ansprüche 2 bis 4, dadurch gekennzeichnet, dass der Abstand (L) zwischen der ersten Lochplatte (24) und der zweiten Lochplatte (17a) und die geometrischen Abmessungen (I,a,A) der zweiten Öffnungen (27a) derart gewählt werden, dass die zweiten Öffnungen (27a) in Kombination mit dem zwischen der ersten (24) und der zweiten (17a) Lochplatte angeordneten ersten Zwischenraum (26) Helmholtzresonatoren ergeben, deren Resonanzfrequenz im wesentlichen im Bereich der im Verbrennungsraum (23) auftretenden akustischen Schwingungen (31) liegt.
- Brennkammer (10) nach den Ansprüchen 3 und 5, dadurch gekennzeichnet, dass die dritte Lochplatte (29) schallabsorbierend ausgestaltet ist.
- Brennkammer (10) nach Anspruch 6, dadurch gekennzeichnet, dass die zweite Lochplatte (17a) eine Dicke (I) im Bereich von 0.1 bis 1 cm, insbesondere bevorzugt von 0.6 cm aufweist, dass das Flächenverhältnis der akustisch relevanten Teilflächen (A) des ersten Zwischenvolumens (26) und der Flächen (a) der zweiten Öffnungen (27a) im Bereich von 5 bis 10, insbesondere bevorzugt von 8, ist, dass der Abstand (L) der ersten (24) von der zweiten (17a) Lochplatte 0.1 bis 1 cm, insbesondere bevorzugt 0.6 cm, ist, dass das Produkt aus Kontraktionsverhältnis der dritten Öffnungen (28) und grösster Machzahl im Bereich von 1 bis 0.5 ist, und dass das Flächenverhältnis der akustisch relevanten Teilflächen (B) im Verbrennungsraum (23) und der akustisch relevanten Teilflächen (A) des ersten Zwischenvolumens (26) in einem Bereich von 1 bis 2 ist, so dass die Helmholtzresonatoren in Kombination mit der schallabsorbierenden Lochplatte (29) im Verbrennungsraum (23) auftretende akustische Schwingungen (31) mit Frequenzen im Bereich von 2 bis 6 kHz absorbieren.
- Brennkammer (10) nach einem der Ansprüche 2 bis 4, dadurch gekennzeichnet, dass der Abstand (L1) zwischen der ersten Lochplatte (24) und der dritten Lochplatte (17b) und die geometrischen Abmessungen (I1,a,A) der dritten Öffnungen (27b) derart gewählt werden, dass die dritten Öffnungen (27a) in Kombination mit dem zwischen der ersten (24) und der dritten (17b) Lochplatte angeordneten Zwischenraum Helmholtzresonatoren ergeben, deren Resonanzfrequenz im wesentlichen im Bereich der im Verbrennungsraum (23) auftretenden akustischen Schwingungen (31) liegt.
- Brennkammer (10) nach den Ansprüchen 3 und 8, dadurch gekennzeichnet, dass die zweite Lochplatte (34) schallabsorbierend ausgestaltet ist.
- Brennkammer (10) nach Anspruch 9, dadurch gekennzeichnet, dass die dritte Lochplatte (17b) eine Dicke (I1) im Bereich von 0.1 bis 1 cm, insbesondere bevorzugt von 0.6 cm aufweist, dass das Flächenverhältnis der akustisch relevanten Teilflächen (A) des Zwischenraums und der Flächen (a) der dritten Öffnungen (27b) im Bereich von 5 bis 10, insbesondere bevorzugt von 8, ist, dass der Abstand (L1) der ersten (24) von der dritten (17b) Lochplatte 0.1 bis 1 cm, insbesondere bevorzugt 0.6 cm, ist, dass das Produkt aus Kontraktionsverhältnis der zweiten Öffnungen (33) und grösster Machzahl im Bereich von 2.5 bis 0.5 ist, und. dass das Flächenverhältnis der akustisch relevanten Teilflächen (B) im Verbrennungsraum (23) und der akustisch relevanten Teilflächen (A) des ersten Zwischenvolumens (26) in einem Bereich von 1 bis 2 ist, so dass die Helmholtzresonatoren in Kombination mit der schallabsorbierenden Lochplatte (34) im Verbrennungsraum (23) auftretende akustische Schwingungen (31) mit Frequenzen im Bereich von 2 bis 6 kHz absorbieren.
- Brennkammer (10) nach einem der Ansprüche 2 bis 10, dadurch gekennzeichnet, dass die zweite (17a,34) und die dritte (29,17b) Lochplatte unmittelbar aufeinander aufliegen, und dass die zweiten (27a,33) und die dritten (28,27b) Öffnungen gleich verteilt und konzentrisch angeordnet sind.
- Brennkammer (10) nach Anspruch 11, dadurch gekennzeichnet, dass die zweite (17a,34) und die dritte (29,17b) Lochplatte von einem Lochblech (36) gebildet werden, welches gestufte Öffnungen (37) aufweist, deren der ersten Lochplatte (24) zugewandte erste Stufenteile (38) den zweiten Öffnungen (27a,33) entsprechen, und deren dem Verbrennungsraum (23) zugewandte Stufenteile (39) den dritten Öffnungen (28,27b) entsprechen.
Priority Applications (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE59809097T DE59809097D1 (de) | 1998-09-30 | 1998-09-30 | Brennkammer für eine Gasturbine |
EP98810983A EP0990851B1 (de) | 1998-09-30 | 1998-09-30 | Brennkammer für eine Gasturbine |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
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EP98810983A EP0990851B1 (de) | 1998-09-30 | 1998-09-30 | Brennkammer für eine Gasturbine |
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EP0990851A1 EP0990851A1 (de) | 2000-04-05 |
EP0990851B1 true EP0990851B1 (de) | 2003-07-23 |
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EP98810983A Expired - Lifetime EP0990851B1 (de) | 1998-09-30 | 1998-09-30 | Brennkammer für eine Gasturbine |
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DE (1) | DE59809097D1 (de) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US7752846B2 (en) | 2004-05-05 | 2010-07-13 | Alstom Technology Ltd | Combustion chamber for a gas turbine |
Families Citing this family (14)
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JP2002039533A (ja) * | 2000-07-21 | 2002-02-06 | Mitsubishi Heavy Ind Ltd | 燃焼器、ガスタービン及びジェットエンジン |
US6530221B1 (en) * | 2000-09-21 | 2003-03-11 | Siemens Westinghouse Power Corporation | Modular resonators for suppressing combustion instabilities in gas turbine power plants |
US6973790B2 (en) | 2000-12-06 | 2005-12-13 | Mitsubishi Heavy Industries, Ltd. | Gas turbine combustor, gas turbine, and jet engine |
JP3676228B2 (ja) * | 2000-12-06 | 2005-07-27 | 三菱重工業株式会社 | ガスタービン燃焼器およびガスタービン並びにジェットエンジン |
DE60135436D1 (de) | 2001-01-09 | 2008-10-02 | Mitsubishi Heavy Ind Ltd | Gasturbinenbrennkammer |
WO2004051063A1 (ja) * | 2002-12-02 | 2004-06-17 | Mitsubishi Heavy Industries, Ltd. | ガスタービン燃焼器、及びこれを備えたガスタービン |
EP1624250A1 (de) * | 2004-08-03 | 2006-02-08 | Siemens Aktiengesellschaft | Vorrichtung zur Dämpfung von thermoakustichen Schwingungen in Brennkammern |
GB0425794D0 (en) | 2004-11-24 | 2004-12-22 | Rolls Royce Plc | Acoustic damper |
EP2282120A1 (de) * | 2009-06-26 | 2011-02-09 | Siemens Aktiengesellschaft | Brennkammeranordnung zur Dämpfung von thermoakustischen Schwingungen, Gasturbine und Verfahren zum Betrieb einer solchen Gasturbine |
ES2400267T3 (es) | 2009-08-31 | 2013-04-08 | Alstom Technology Ltd | Dispositivo de combustión de una turbina de gas |
EP2385303A1 (de) | 2010-05-03 | 2011-11-09 | Alstom Technology Ltd | Verbrennungsvorrichtung für eine Gasturbine |
US20140123649A1 (en) * | 2012-11-07 | 2014-05-08 | Juan E. Portillo Bilbao | Acoustic damping system for a combustor of a gas turbine engine |
EP3051206B1 (de) * | 2015-01-28 | 2019-10-30 | Ansaldo Energia Switzerland AG | Sequentielle gasturbinen-brennkammeranordnung mit einem mischer und einem dämpfer |
CN113757720B (zh) * | 2021-09-18 | 2023-01-31 | 北京航空航天大学 | 燃烧振荡控制装置、方法及燃烧室 |
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CH284190A (de) * | 1950-09-04 | 1952-07-15 | Bbc Brown Boveri & Cie | Metallene Brennkammer zur Erzeugung heisser Gase, insbesondere Treibgase für Gasturbinenanlagen. |
EP0576717A1 (de) * | 1992-07-03 | 1994-01-05 | Abb Research Ltd. | Gasturbinen-Brennkammer |
DE59208193D1 (de) | 1992-07-03 | 1997-04-17 | Abb Research Ltd | Nachbrenner |
DE59208715D1 (de) | 1992-11-09 | 1997-08-21 | Asea Brown Boveri | Gasturbinen-Brennkammer |
CA2141066A1 (en) | 1994-02-18 | 1995-08-19 | Urs Benz | Process for the cooling of an auto-ignition combustion chamber |
DE69526615T2 (de) * | 1994-09-14 | 2002-11-28 | Mitsubishi Heavy Ind Ltd | Wandaufbau für die Austrittsdüse eines Überschall-Strahltriebwerks |
US5644918A (en) | 1994-11-14 | 1997-07-08 | General Electric Company | Dynamics free low emissions gas turbine combustor |
GB2309296B (en) * | 1995-10-11 | 2000-02-09 | Europ Gas Turbines Ltd | Gas turbine engine combuster |
ATE232287T1 (de) * | 1997-07-15 | 2003-02-15 | Alstom Switzerland Ltd | Schwingungsdämpfende brennkammerwandstruktur |
-
1998
- 1998-09-30 DE DE59809097T patent/DE59809097D1/de not_active Expired - Lifetime
- 1998-09-30 EP EP98810983A patent/EP0990851B1/de not_active Expired - Lifetime
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US7752846B2 (en) | 2004-05-05 | 2010-07-13 | Alstom Technology Ltd | Combustion chamber for a gas turbine |
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