EP0694740A2 - Combustion chamber - Google Patents

Abstract

The combustion chamber has two stages (1,2) in series in the gas flow direction. On the head side of the first stage, there is a mixer (100) which forms a fuel-air mixture. Downstream of this mixer there is a catalyser (3), in which the mixture is fully burnt. The mixture is such that an adiabatic flame temp. of between 800 and 1100 deg. C is maintained. Downstream of the catalyser there are vortex generators (200), producing an intensively swirled flow. Downstream of these, fuel (9) is injected and self-combustion takes place. A cross-section step (12), marking the beginning of the second stage, provides a stabilising backflow of the flame front (21). <IMAGE>

Description

Technical field

The present invention relates to a combustion chamber according to the preamble of claim 1.

State of the art

In combustion chambers with a wide load range, there is always the problem of how combustion can be operated with low emissions and with high efficiency. Most of the NOx emissions are in the foreground, but it has been shown that UHC (= unsaturated coal-water substances) and CO emissions must also be minimized in the future. In particular when it comes to using liquid and / or gaseous fuels, it quickly becomes apparent that the design for one type of fuel, for example for oil, and aimed at minimizing pollutant emissions, for example NOx emissions, cannot be transferred satisfactorily to other types of debt collection and other pollutant emissions. With multi-stage combustion chambers, the aim is to run the second stage lean. However, this is only possible if on Entry of this second stage always has a constant temperature, so that sufficient burnout can be achieved in the second stage even with a small amount of fuel, ie the mixture in the first stage would have to be kept largely constant, which is not possible with the known diffusion burners, for example. As far as can be seen, such a combustion chamber is not part of the prior art.

Presentation of the invention

The invention seeks to remedy this. The invention, as characterized in the claims, is based on the object, in a combustion chamber of the type mentioned, to minimize all pollutant emissions occurring during combustion, regardless of the type of fuel used.

Basically, the aim here is to keep the mixture constant in the first stage so that UHC and CO emissions can be prevented. The mixer used in the first stage mixes fuel and air evenly, whereby in the case of oil, droplet evaporation takes place. If a premix burner according to EP-A1-0 321 809 is used for the above-mentioned mixing, then this undergoes a modification regarding the aerodynamics, which is manifested in the fact that the swirl is significantly reduced. This is done by 20-100% wider air inlet slots, or by increasing the number of these slots. The new premix burner is characterized by the fact that it is used alone as a mixer and is no longer able to create a backflow zone. Downstream of this mixer is a catalytic converter in which the fuel / air mixture is completely burned. The mixture is selected in such a way that typical adiabatic flame temperatures between 800 ° and 1100 ° C are reached, thus precluding thermal destruction of the catalyst is. This is a great advantage compared to other catalytic processes for high temperatures. Due to the low temperatures, there is no homogeneous gas phase reaction, but only a reaction on the active surfaces. The NOx production of such a chemical reaction is very low, much less than 1 ppmv. A largely NOx-free hot gas is available at the end of the catalyst.

After exiting the catalyst, the flow is accelerated to approximately 80-120 m / s. Vortex generators ensure a vortex-intensive flow in order to mix in the fuel injected downstream as quickly as possible. The constant temperature at the entrance to the second stage ensures that the mixture ignites independently of the amount of fuel injected into the second stage. Here, too, it can be seen that the fuel injection into a hot gas produces very little NOx.

Another important advantage of the invention is that the power control over the gas turbine load can be carried out essentially by adjusting the amount of fuel in the second stage.

Advantageous and expedient developments of the task solution according to the invention are characterized in the further dependent claims.

Exemplary embodiments of the invention are explained in more detail below with reference to the drawings. All elements not necessary for the immediate understanding of the invention have been omitted. Identical elements are provided with the same reference symbols in the various figures. The direction of flow of the media is indicated by arrows.

Brief description of the drawings

Fig. 1

eine Brennkammer, als Ringbrennkammer konzipiert, zwischen zwei Strömungsmaschinen angeordnet,

Fig. 2

einen Mischer in perspektivischer Darstellung, entsprechend aufgeschnitten,

Fig. 3-5

entsprechende Schnitte durch verschiedene Ebenen des Mischers,

Fig. 6

eine perspektivische Darstellung des Wirbel-Generators,

Fig. 7

eine Ausführungsvariante des Wirbel-Genenerators,

Fig. 8

eine Anordnungsvariante des Wirbel-Generators nach Fig. 7,

Fig. 9

einen Wirbel-Generators im Vormischkanal,

Fig. 10-16

Varianten der Brennstoffzuführung im Zusammenhang mit Wirbel-Generatoren.

It shows:

Fig. 1

a combustion chamber, designed as an annular combustion chamber, arranged between two turbomachines,

Fig. 2

a mixer in perspective, cut open accordingly,

Fig. 3-5

appropriate cuts through different levels of the mixer,

Fig. 6

a perspective view of the vortex generator,

Fig. 7

a variant of the vortex generator,

Fig. 8

7 shows a variant of the arrangement of the vortex generator according to FIG. 7,

Fig. 9

a vortex generator in the premixing channel,

Fig. 10-16

Variants of fuel supply in connection with vortex generators.

Ways of carrying out the invention, commercial usability

1 shows, as can be seen from the shaft axis 16, an annular combustion chamber which essentially has the shape of a coherent annular or quasi-annular cylinder. In addition, such a combustion chamber can also consist of a number of axially, quasi-axially or helically arranged and individually closed combustion chambers. As such, the combustion chamber can also consist of a single one Pipe exist. 1 consists of a first 1 and a second stage 2, which are connected in series, and the second stage 2 consists of the actual combustion zone 11. The first stage 1 in the direction of flow initially consists of a number of mixers 100 arranged in the circumferential direction, the mixer itself being essentially derived from the burner according to EP-0 321 809. As far as the following description of the combustion chamber is concerned, only the sectional plane according to FIG. 1 is used. Of course, all components of the combustion chamber are arranged in a corresponding number in the circumferential direction. A compressor 18 acts in this mixer 100, in which the intake air 17 is compressed. The air 115 then supplied by the compressor has a pressure of 10-40 bar at a temperature of 300-600 ° C. This air 115 flows into the mixer 100, the mode of operation of which is described in more detail in FIGS. 2-5. After a short transition piece 122 downstream of the mixer 100, the fuel / air mixture 19 provided in the mixer 100 reaches a catalyst 3, in which this mixture 19 is completely combusted. The mixture 19 is selected such that typical adiabatic flame temperatures between 800 and 1050 ° C. are reached, with the result that the thermal destruction of the catalyst 3 is excluded. Because of the relatively low temperature, there is no homogeneous gas phase reaction, but only a reaction on the active surfaces of the catalyst 3. The NOx production of such a chemical reaction is very low, much less than 1 ppmv. A largely NOx-free hot gas 4 is thus available at the end of the catalyst 3. The catalyst 3 itself consists of a first very active stage, which initiates the fuel conversion. A palladium oxide is preferably used as the material here. The next stages of the catalyst 3 can consist of other materials, for example of platinum. The fuel is then largely converted in the catalytic converter 3, the flow velocity in the Catalyst 3 is less than about 30 m / s. After emerging from the catalyst 3, the hot gases 4 flow into an inflow zone 5 and are accelerated to approximately 80-120 m / s. The inflow zone 5 is equipped on the inside and in the circumferential direction of the channel wall 6 with a series of vortex-generating elements 200, hereinafter only called vortex generators, which will be discussed in more detail below. The hot gases 4 are swirled by the vortex generators 200 such that no recirculation areas occur in the wake of the vortex generators 200 mentioned in the subsequent premixing section 7. In the circumferential direction of this premixing section 7, which is designed as a Venturi channel, a plurality of fuel lances 8 are arranged, which take over the supply of a fuel 9 and supporting air 10. These media can be supplied to the individual fuel lances 8, for example, via a ring line (not shown). The swirl flow triggered by the vortex generators 200 ensures a large-scale distribution of the introduced fuel 9, if necessary also the admixed supporting air 10. Furthermore, the swirl flow ensures a homogenization of the mixture of combustion air and fuel. The fuel 9 injected into the hot gases 4 by the fuel lance 8 triggers self-ignition, provided that these hot gases 4 have the specific temperature which the fuel-dependent auto-ignition can trigger. If the ring combustion chamber is operated with a gaseous fuel, a temperature of the hot gases 4 of more than 800 ° C. must be present to initiate self-ignition, which is also present here. With such a combustion, as already appreciated above, there is a risk of a flashback. This problem is remedied by, on the one hand, designing the premixing zone 7 as a venturi channel and, on the other hand, disposing the injection of the fuel 9 in the region of the largest constriction in the premixing zone 7. The constriction in the premixing zone 7 reduces the turbulence by increasing the axial speed, which minimizes the risk of kickback by reducing the turbulent flame speed. On the other hand, the large-scale distribution of the fuel 9 is still guaranteed, since the peripheral component of the swirl flow originating from the vortex generators 200 is not impaired. The combustion zone 11 follows the relatively short premixing zone 7. The transition between the two zones is formed by a radial cross-sectional jump 12, which initially indicates the flow cross-section of the combustion zone 11. A flame front 21 also arises in the plane of the cross-sectional jump 12. In order to prevent the flame from reigniting into the interior of the premix zone 7, the flame front 21 must be kept stable. For this purpose, the vortex generators 200 are designed such that no recirculation takes place in the premixing zone 7; only after the sudden cross-sectional expansion does the swirl flow burst. The swirl flow supports the rapid re-application of the flow behind the cross-sectional jump 12, so that a high burn-out with a short overall length can be achieved by utilizing the volume of the combustion zone 11 as fully as possible. Within this cross-sectional jump 12, a flow-like edge zone is formed during operation, in which vortex detachments occur due to the prevailing negative pressure, which then lead to stabilization of the flame front. These corner vortices 20 also form the ignition zones within the second stage 2. The hot working gases 13 provided in the combustion zone 11 then act on a downstream turbine 14. The exhaust gases 15 can then be used to operate a steam cycle, in the latter case the switching then Combined system is.

In summary, it can be said that due to the high flow rate, the onset of post-combustion in the flow channel is impossible. When burning oil an immediate ignition can be prevented by adding water. As already explained, the cross-sectional jump 12 serves to stabilize the afterburning. The self-ignition of the mixture takes place in the corner vertebrae 20 due to the long residence time. The flame front 21 progresses towards the center of the combustion zone 11. The CO burnout is also completed shortly downstream of the point of union of the two flame front parts. Typical combustion temperatures are 1300-1600 ° C. The process of injecting fuel into a hot gas is predestined to produce very little NOx.

The proposed method also behaves very well with regard to a wide load range. Since the mixture in the first stage 1 is always kept largely constant, the UHC or CO emissions can also be prevented. The constant temperature at the entrance to the second stage 2 ensures reliable self-ignition of the mixture, regardless of the amount of fuel in the second stage 2. The inlet temperature is still high enough to achieve sufficient burnout in the second stage 2 even with a small amount of fuel . The output control via the gas turbine load essentially takes place by adapting the fuel quantity in the second stage 2. The controllable compressor 18 ensures that the minimum combustion temperature at the outlet of the catalytic converter 3 is not undercut at zero load.

In order to better understand the structure of the mixer 100, it is advantageous if the individual cuts according to FIGS. 3-5 are used simultaneously with FIG. 2. Furthermore, in order not to make FIG. 2 unnecessarily confusing, the guide plates 121a, 121b shown schematically according to FIGS. 3-5 have only been hinted at. In the description of FIG. 2, reference is made below to the remaining FIGS. 3-5 as required.

The mixer 100 according to FIG. 2 consists of two hollow, conical partial bodies 101, 102 which are nested one inside the other. The offset of the respective central axis or longitudinal axis of symmetry 201b, 202b of the conical partial bodies 101, 102 to one another creates a tangential air inlet slot 119, 120 on both sides, in a mirror-image arrangement (FIGS. 3-5), through which the combustion air 115 enters the interior of the Mixer 100, ie flows into the cone cavity 114. The conical shape of the partial bodies 101, 102 shown in the flow direction has a specific fixed angle. Of course, depending on the operational use, the partial bodies 101, 102 can have an increasing or decreasing cone inclination in the direction of flow, similar to a trumpet or. Tulip. The last two forms are not included in the drawing, since they can be easily understood by a person skilled in the art. The two tapered partial bodies 101, 102 each have a cylindrical starting part 101a, 102a, which, similarly to the conical partial bodies 101, 102, also run offset from one another, so that the tangential air inlet slots 119, 120 are present over the entire length of the mixer 100. In the area of the cylindrical initial part, a nozzle 103 is accommodated, the injection 104 of which coincides approximately with the narrowest cross section of the conical cavity 114 formed by the conical partial bodies 101, 102. The injection capacity and the type of this nozzle 103 depend on the specified parameters of the respective mixer 100. Of course, the mixer 100 can be designed purely conical, that is to say without cylindrical starting parts 101a, 102a. The conical sub-bodies 101, 102 further each have a fuel line 108, 109, which are arranged along the tangential inlet slots 119, 120 and are provided with injection openings 117, through which a gaseous fuel 113 is preferably injected into the combustion air 115 flowing through there, such as arrows 116 symbolize this. These fuel lines 108, 109 are preferably at the latest at the end of the tangential Inflow, prior to entering the cone cavity 114, is placed in order to obtain an optimal air / fuel mixture. In the area of the transition piece 122, the outlet opening of the mixer 100 merges into a front wall 110, in which a number of bores 110a are provided. The latter come into operation when necessary and ensure that dilution air or cooling air 110b is supplied to the front part of the transition piece 122. The fuel brought in through the nozzle 103 is a liquid fuel 112, which can be enriched with a recirculated exhaust gas at most. This fuel 112 is injected into the cone cavity 114 at an acute angle. A conical fuel profile 105 is thus formed from the nozzle 103 and is enclosed by the rotating combustion air 115 flowing in tangentially. In the axial direction, the concentration of the fuel 112 is continuously reduced to an optimal mixture by the inflowing combustion air 115. If the mixer 100 is operated with a gaseous fuel 113, this is preferably done via opening nozzles 117, the formation of this fuel / air mixture taking place directly at the end of the air inlet slots 119, 120. When the fuel 112 is injected via the fuel nozzle 103, the optimum, homogeneous fuel concentration over the cross section is achieved at the end of the mixer 100. If the combustion air 115 is additionally preheated or enriched with a recirculated exhaust gas, this sustainably supports the evaporation of the liquid fuel 112. The same considerations also apply if, instead of gaseous, liquid fuels are supplied via the lines 108, 109. When designing the conical partial bodies 101, 102 with respect to the cone angle and the width of the tangential air inlet slots 119, 120, strict limits must be adhered to so that the desired flow field of the combustion air 115 can be set at the outlet of the mixer 100. In general, it can be said that the cross section of the tangential air inlet slots 119, 120 is minimized is predestined to form a backflow zone 106. In our case, however, no backflow zone is to be formed, which is why the aerodynamics of the mixer 100 must be such that the swirl can be reduced significantly. This is done by 20-100% wider air inlet slots 119, 120 compared to a same body that serves as a premix burner. Another way of preventing the formation of a backflow zone is to increase the number of air inlet slots, and at the same time the number of partial bodies increases accordingly. The axial speed within the mixer 100 can be changed by a corresponding supply, not shown, of an axial combustion air flow. The construction of the mixer 100 is furthermore excellently suitable for changing the size of the tangential air inlet slots 119, 120, with which a relatively large operational bandwidth can be recorded without changing the overall length of the mixer 100. Of course, the partial bodies 101, 102 can also be displaced relative to one another in another plane, as a result of which even an overlap thereof can be controlled. It is even possible to interleave the partial bodies 101, 102 in a spiral manner by counter-rotating movement.

3-5 now shows the geometrical configuration of the guide plates 121a, 121b. They have a flow introduction function, which, depending on their length, extend the respective end of the tapered partial bodies 101, 102 in the direction of flow relative to the combustion air 115. The channeling of the combustion air 115 into the cone cavity 114 can be optimized by opening or closing the guide plates 121a, 121b around a pivot point 123 located in the region of the entry of this channel into the cone cavity 114, in particular this is necessary if the original gap size of the tangential air inlet slots 119, 120 is to be changed from the above motives. Of course, these dynamic arrangements can also be provided statically are formed by the need for baffles as a fixed component with the tapered partial bodies 101, 102. Mixer 100 can also be operated without baffles, or other aids can be provided for this.

The actual inflow zone 5 is not shown in FIGS. 6, 7 and 8. In contrast, the flow of hot gases 4 is shown by an arrow, which also specifies the direction of flow. According to these figures, a vortex generator 200, 201, 202 essentially consists of three freely flowing triangular surfaces. These are a roof surface 210 and two side surfaces 211 and 213. In their longitudinal extent, these surfaces run at certain angles in the direction of flow. The side walls of the vortex generators 200, 201, 202, which preferably consist of right-angled triangles, are fixed with their long sides on the channel wall 6 already mentioned, preferably gas-tight. They are oriented so that they form a joint on their narrow sides, including an arrow angle α. The joint is designed as a sharp connecting edge 216 and is perpendicular to each channel wall 6 with which the side surfaces are flush. The two side surfaces 211, 213 including the arrow angle α are symmetrical in shape, size and orientation in FIG. 4, they are arranged on both sides of an axis of symmetry 217 which is oriented in the same direction as the channel axis.
The roof surface 210 lies against the same channel wall 6 as the side surfaces 211, 213 with a very narrow edge 215 running transversely to the flow channel. Its longitudinal edges 212, 214 are flush with the longitudinal edges of the side surfaces 211 protruding into the flow channel , 213. The roof surface 210 extends at an angle of inclination Θ to the channel wall 6, the longitudinal edges 212, 214 of which, together with the connecting edge 216, form a point 218. Of course, the vortex generator 200, 201, 202 can also be provided with a bottom surface with which he is suitably attached to the channel wall 6. Such a floor area is, however, unrelated to the mode of operation of the element.

The mode of operation of the vortex generator 200, 201, 202 is as follows: When flowing around the edges 212 and 214, the main flow is converted into a pair of opposing vortices, as is schematically outlined in the figures. The vortex axes lie in the axis of the main flow. The number of swirls and the location of the vortex breakdown (vortex breakdown), if the latter is aimed for, are determined by appropriate selection of the angle of attack Θ and the arrow angle α. With increasing angles, the vortex strength or the number of swirls is increased, and the location of the vortex bursting shifts upstream into the region of the vortex generator 200, 201, 202 itself. Depending on the application, these two angles Θ and α are due to structural conditions and determined by the process itself. These vortex generators only have to be adapted in terms of length and height, as will be explained in more detail below under FIG. 9.

In FIG. 6, the connecting edge 216 of the two side surfaces 211, 213 forms the downstream edge of the vortex generator 200. The edge 215 of the roof surface 210 which runs transversely to the flow through the channel is thus the edge which is first acted upon by the channel flow.

FIG. 7 shows a so-called half "vortex generator" based on a vortex generator according to FIG. 6. In the vortex generator 201 shown here, only one of the two side surfaces is provided with the arrow angle α / 2. The other side surface is straight and oriented in the direction of flow. In contrast to the symmetrical vortex generator, only one vortex is generated on the arrowed side, as is shown in the figure. Accordingly, it is downstream this vortex generator does not have a vortex-neutral field, but a swirl is forced on the flow.

FIG. 8 differs from FIG. 6 in that the sharp connecting edge 216 of the vortex generator 202 is the point which is first acted upon by the channel flow. The element is therefore rotated by 180 °. As can be seen from the illustration, the two opposite vortices have changed their sense of rotation.

9 shows the basic geometry of a vortex generator 200 installed in a channel 5. As a rule, the height h of the connecting edge 216 will be coordinated with the channel height H, or the height of the channel part which is assigned to the vortex generator that the vortex generated immediately downstream of the vortex generator 200 already reaches such a size that the full channel height H is filled. This leads to a uniform speed distribution in the cross-section applied. Another criterion that can influence the ratio of the two heights h / H to be selected is the pressure drop that occurs when the vortex generator 200 flows around. It goes without saying that the pressure loss coefficient also increases with a larger ratio h / H.

The vortex generators 200, 201, 202 are mainly used when it comes to mixing two flows. The main flow 4 as hot gases attacks the transverse edge 215 or the connecting edge 216 in the direction of the arrow. The secondary flow in the form of a gaseous and / or liquid fuel, which is possibly enriched with a portion of supporting air (see FIG. 1), has a much smaller one Mass flow as the main flow. In the present case, this secondary flow is introduced into the main flow downstream of the vortex generator, as can be seen particularly well from FIG. 1.

In the example shown in FIG. 1, four vortex generators 200 are distributed at a distance over the circumference of the channel 5. Of course, the vortex generators can also be strung together in the circumferential direction so that no gaps are left on the channel wall 6. The vortices to be generated are ultimately decisive for the choice of the number and the arrangement of the vortex generators.

FIGS. 10-16 show further possible forms of introducing the fuel into the hot gases 4. These variants can be combined in a variety of ways with one another and with a central fuel injection, as can be seen, for example, from FIG. 1.

In Fig. 10, in addition to channel wall bores 220, which are located downstream of the vortex generators, the fuel is also injected via wall bores 221, which are located directly next to the side surfaces 211, 213 and in their longitudinal extent in the same channel wall 6, on the the vortex generators are arranged. The introduction of the fuel through the wall bores 221 gives the generated vortices an additional impulse, which extends the lifespan of the vortex generator.

11 and 12, the fuel is injected via a slot 222 or via wall bores 223, both arrangements being located directly in front of the edge 215 of the roof surface 210 running transversely to the flowed channel and in the longitudinal extension thereof in the same channel wall 6 on which the Vortex generators are arranged. The geometry of the wall bores 223 or the slot 222 is selected such that the fuel is introduced into the main flow 4 at a certain injection angle and largely shields the post-placed vortex generator as a protective film against the hot main flow 4 by flow around it.

In the examples described below, the secondary flow (cf. above) is first introduced into the hollow interior of the vortex generators via guides (not shown) through the channel wall 6. This creates an internal cooling facility for the vortex generators without providing any additional equipment.

13, the fuel is injected via wall bores 224, which are located inside the roof surface 210 directly behind and along the edge 215 running transversely to the flow channel. The vortex generator is cooled here more externally than internally. The emerging secondary flow forms when flowing around the roof surface 210 a protective layer shielding it against the hot main flow 4.

In FIG. 14, the fuel is injected via wall bores 225, which are staggered within the roof surface 210 along the line of symmetry 217. With this variant, the channel walls 6 are particularly well protected from the hot main flow 4, since the fuel is first introduced on the outer circumference of the vortex.

15, the fuel is injected via wall bores 226, which are located in the longitudinal edges 212, 214 of the roof surface 210. This solution ensures good cooling of the vortex generators, since the fuel escapes from its extremities and thus completely flushes the inner walls of the element. The secondary flow is fed directly into the resulting vortex, which leads to defined flow conditions.

16, the injection takes place via wall bores 227, which are located in the side surfaces 211 and 213, on the one hand in the area of the longitudinal edges 212 and 214, and on the other hand in the area of the connecting edge 216. This variant has a similar effect like those of Fig. 10 (bores 221) and Fig. 15 (bores 226).

Reference list

1

First stage

2nd

Second step

3rd

catalyst

4th

Hot gases, main flow

5

Inflow zone, channel of the inflow zone

6

Canal wall of the inflow zone

7

Premixing zone

8th

Fuel lance

9

fuel

10th

Support air

11

Combustion zone

12th

Cross-sectional jump

13

Hot working gases

14

turbine

15

Exhaust gases

16

Shaft axis

17th

Intake air

18th

compressor

19th

Air / fuel mixture

20th

Corner swirls, ignition zones

21

Flame front

100

mixer

101, 102

Partial body

101a, 102a

Cylindrical starting parts

101b, 102b

Longitudinal symmetry axes

103

Fuel nozzle

104

Fuel injection

105

Fuel injection profile

108, 109

Fuel lines

110

Front wall

110a

Air holes

110b

Cooling air

112

Liquid fuel

113

Gaseous fuel

114

Cone cavity

115

Combustion air

116

Fuel injection

117

Fuel nozzles

119, 120

Tangential air inlet slots

121a, 121b

Baffles

122

Transition piece

123

Pivot point of the guide plates

200, 201, 202

Vortex generators

210

Roof area

211, 213

Side faces

212, 214

Longitudinal edges

215

Transverse edge

216

Connecting edge

217

Axis of symmetry

218

top

220-227

Drilling holes for fuel injection

L, h,

Dimensions of the vortex generator

H

Height of the channel

α

Arrow angle

Θ

Angle of attack

Claims (13)

Combustion chamber, which essentially consists of a first stage (1) and a second stage (2) connected downstream in the flow direction, the first stage (1) being arranged downstream and the second stage (2) being arranged upstream of flow machines (18, 14), characterized in that the first stage (1) has a mixer (100) on the head side to form a fuel / air mixture (19), that a catalyst (3) is arranged on the downstream side of the mixer (100), that on the downstream side of the catalyst (3 ) Vortex generators (200, 201, 202) are present, that on the downstream side of the vortex generators (200, 201, 202) a gaseous and / or liquid fuel (9) can be injected into a gaseous main flow (4) that the in The second stage (2) following the flow direction has a cross-sectional jump (12) which indicates the initial flow cross section of the second stage (2). Combustion chamber according to claim 1, characterized in that the first stage (1) downstream of the vortex generators (200, 201, 202) and before entering the second stage (2) forms a venturi-shaped channel that the fuel (9) and a Support air (10) can be injected through a fuel nozzle (8) along and / or across the main flow (4) in the area of the largest constriction of the venturi-shaped channel. Combustion chamber according to claim 1, characterized in that a vortex generator (200) has three freely flowing surfaces which extend in the direction of flow, one of which forms the roof surface (210) and the other two the side surfaces (211, 213), that the side surfaces (211, 213) are flush with an identical wall segment of the channel (5) and enclose the arrow angle (α) with one another, that the roof surface (210) with an edge (215) running transversely to the flowed channel (5) on the same wall segment of the channel (6) rests like the side surfaces (211, 213), and that longitudinal edges (212, 214) of the roof surface (210) are flush with the longitudinal edges of the side surfaces (211, 213) projecting into the channel (5) and run at an angle of attack (Θ) to the wall segment of the channel (5). Combustion chamber according to claim 3, characterized in that the two side surfaces (211, 213) of the vortex generator (200) including the arrow angle (α) are arranged symmetrically about an axis of symmetry (217). Combustion chamber according to claim 3, characterized in that the two side surfaces (211, 213) including the arrow angle (α, α / 2) comprise a connecting edge (116) which together with the longitudinal edges (212, 214) of the roof surface (210 ) form a tip (218), and that the connecting edge (216) lies in the radial of the circular channel (5). Combustion chamber according to claim 5, characterized in that the connecting edge (216) and / or the longitudinal edges (212, 214) of the roof surface (210) is at least approximately sharp. Combustion chamber according to claims 1, 3, 4, 5, characterized in that the axis of symmetry (217) of the vortex generator (200) runs parallel to the channel axis, that the connecting edge (216) of the two side surfaces (211, 213) is the downstream one Forms edge of the vortex generator (200), and that the edge (215) of the roof surface (210) which runs transversely to the channel (5) through which flow flows is the edge which is acted upon first by the main flow (4). Combustion chamber according to claim 1, characterized in that the ratio height (h) of the vortex generator to the height (H) of the channel (5) is selected such that the vortex generated immediately downstream of the vortex generator (200) is the full height ( H) of the channel (5) and the full height (h) of the channel part assigned to the vortex generator (200). Combustion chamber according to claim 1, characterized in that the burner (100) consists of at least two hollow, conical, part-bodies (101, 102) nested one inside the other in the direction of flow, the respective longitudinal axes of symmetry (101b, 102b) of which are offset with respect to one another such that the adjacent walls of the part-bodies (101, 102) in their longitudinal extension form tangential channels (119, 120) for a combustion air flow (115) that in the part bodies (101, 102) formed cone cavity (114) at least one fuel nozzle (103) is present. Combustion chamber according to Claim 9, characterized in that further fuel nozzles (117) are arranged in the region of the tangential channels (119, 120) in their longitudinal extent. Combustion chamber according to claim 9, characterized in that the partial bodies (101, 102) widen at a fixed angle in the direction of flow, or have an increasing or decreasing taper. Combustion chamber according to claim 9, characterized in that the partial bodies (101, 102) are nested in one another in a spiral manner. Combustion chamber according to claim 1, characterized in that the combustion chamber is an annular combustion chamber.

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