EP0931980B1 - Burner for operating a heat generator - Google Patents

Abstract

The burner consists essentially of a spin generator (100) for the combustion air flow and an arrangement for feeding at least one fuel into the combustion air flow with a mixing path (20) upstream of the spin generator. The mixing path has a number of transition channels in a first path section for passing a flow generated in the spin generator into a mixing tube downstream of the transition channels. A cooled pilot burner system (300) in the lower region of the mixing tube acts upon the combustion chamber after the mixing tube. The pilot burner system has at least one integral igniter (311).

Description

Technical field

The invention relates to a burner for the operation of a heat generator according to Preamble of claim 1.

State of the art

From EP-0 797 051 A2 a burner has become known, the upstream side consists of a swirl generator, the flow formed therein seamlessly in a mixing section is transferred. This is done using one at the beginning of the Mixing section flow geometry formed for this purpose, which consists of transition channels exists, which is sectoral, according to the number of those acting Partial body of the swirl generator, capture the end face of the mixing section and in Flow direction swirl. Downstream of these transition channels the mixing section has a number of filming holes, which one Ensure an increase in the flow velocity along the pipe wall. This is followed by a combustion chamber, the transition between the Mixing section and the combustion chamber formed by a cross-sectional jump in whose plane a backflow zone or backflow bubble forms.

The swirl strength in the swirl generator is selected so that the bursting of the vortex does not occur within the mixing section, but further downstream, as Executed above, in the area of the cross-sectional jump. The length of the mixing section is dimensioned in such a way that there is sufficient mix quality for everyone Types of fuel is guaranteed.

a) Kostenaufwendige separate Durchführung und Abdichtung des Zünders und seiner Leitungen durch die Gehäuse der Gasturbine bis in die Brennkammer,

b) Querzündung innerhalb der Brennkammer aufgrund der geringen Zünderzahl (meist aus Kostengründen nur 1 Zünder);

c) Thermische Belastung des Zünders durch die Positionierung in der Brennkammer, die z.B. Kühlung des Zünders erfordert, weshalb es durch mögliche Undichheiten zu Leckagen kommt;

d) Hohe Anfälligkeit gegen Kondenswasser, wobei Kurzschlüsse den Zündfunken ableiten.

Although this burner guarantees a significant improvement in terms of strengthening flame stability, lower pollutant emissions, lower pulsations, complete burnout, large operating range, good cross-ignition between the various burners, compact design, improved mixture, etc. compared to those from the prior art , it turns out that this burner has no autonomous precautions to be able to drive the gas turbine safely, particularly in its transient load ranges. For example, in the partial load range, the burner must be supported with a support flame. The integration of such precautions in the burner does not have to lead to additional pollutant emissions which could jeopardize the operational and emissions advantages of the burner used.
In addition, these burners are traditionally ignited in gas turbines by means of a special igniter. These igniters usually function with high voltage, which supplies the ignition spark, which either serves as a source of ignition at high power or ignites an ignition torch. These igniters require a separate passage and sealing of the igniter and its lines through the housing of the gas turbine into the combustion chamber. The existing detonator systems have the following disadvantages:

a) Costly separate implementation and sealing of the igniter and its lines through the housing of the gas turbine into the combustion chamber,

b) cross-ignition within the combustion chamber due to the small number of igniters (usually only 1 igniter for cost reasons);

c) Thermal stress on the igniter due to the positioning in the combustion chamber, which, for example, requires cooling of the igniter, which is why leaks occur due to possible leaks;

d) High susceptibility to condensation water, with short circuits diverting the ignition spark.

Presentation of the invention

The invention seeks to remedy this. The invention as set out in the claims is characterized, the task is based on a burner at the beginning to propose precautions which strengthen the flame stability for stable operation, especially in the transient load ranges, ensure always under the further task that the Pollutant emissions should remain low while taking these precautions Measures are taken which relate to the ignition systems mentioned above to eliminate disadvantages.

For this purpose, the burner is expanded in such a way that in the area of its transition a ring-shaped system to provide for the downstream combustion chamber a fuel / air mixture is generally provided as Pilot stage acts. Through a number of circumferential exit bores Appropriate pilot burners are created in the combustion chamber, which are operated in diffusion mode for stability reasons and directly in the combustion chamber.

The main advantages of the subject matter according to the invention are therein see that these individual pilot burners are operated with a low gas content be so that the gas introduced there with a relatively small Air content mixed and as a premixed flame with minimized pollutant emissions burning.

This amount of air initially takes over the cooling of the by means of impingement cooling side facing away from the combustion chamber before it then mixes with the gas and then as a pre-mixed flame with minimized pollutant emissions piloting the combustion chamber is maintained.

This impingement cooling removes the hot gas from the surface of the pilot gas ring and largely isolated from the flame radiation from the combustion chamber, so that the thermal load in this area is significantly reduced.

Even with 100% pilot operation, the individual pilot burners burn, for reasons of stability in diffusion mode, since here the proportion of the cooling air compared to the gas is very small.

The object according to the invention also ensures that the minimized Cooling amount can also be fed to the burning process.

The guided introduction of the cooling air mentioned is also used to in order to provide an ignition device integrated there for the respective pilot burner, with which this integrated ignition device for the pilot burner is part of the burner system, which is interchangeably mounted in the gas turbine. By integrating the ignition device in the burner, several or All pilot burners are equipped with an igniter, which ensures optimal cross-ignition properties be achieved. Preferably the ignition of the Pilot burner using a glow pencil or using a spark plug.

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

Exemplary embodiments of the invention are described below with reference to the drawings explained in more detail. All of which are insignificant for the immediate understanding of the invention Features have been left out. The same elements are in the different Figures with the same reference numerals. The flow direction the media is indicated by arrows.

Brief description of the drawings

Fig. 1

einen als Vormischbrenner ausgelegten Brenner mit einer Mischstrecke stromab eines Drallerzeugers sowie mit Pilotbrennern,

Fig. 2

eine schematische Darstellung des Brenners gemäss Fig. 1 mit Disposition der zusätzlichen Brennstoff-Injektoren,

Fig. 3

einen aus mehreren Schalen bestehenden Drallerzeuger in perspektivischer Darstellung, entsprechend aufgeschnitten,

Fig. 4

einen Querschnitt durch einen zweischaligen Drallerzeuger,

Fig. 5

einen Querschnitt durch einen vierschaligen Drallerzeuger,

Fig. 6

eine Ansicht durch einen Drallerzeuger, dessen Schalen schaufelförmig profiliert sind,

Fig. 7

eine Ausgestaltung der Uebergangsgeometrie zwischen Drallerzeuger und Mischstrecke und

Fig. 8

eine Abrisskante zur räumlichen Stabilisierung der Rückströmzone.

It shows:

Fig. 1

a burner designed as a premix burner with a mixing section downstream of a swirl generator and with pilot burners,

Fig. 2

2 shows a schematic representation of the burner according to FIG. 1 with disposition of the additional fuel injectors,

Fig. 3

a swirl generator consisting of several shells in a perspective view, cut open accordingly,

Fig. 4

a cross section through a double-shell swirl generator,

Fig. 5

a cross section through a four-shell swirl generator,

Fig. 6

2 shows a view through a swirl generator, the shells of which are profiled in a shovel shape,

Fig. 7

an embodiment of the transition geometry between swirl generator and mixing section and

Fig. 8

a tear-off edge for spatial stabilization of the backflow zone.

WAYS OF IMPLEMENTING THE INVENTION, INDUSTRIAL APPLICABILITY

Fig. 1 shows the overall structure of a burner. Initially, a swirl generator 100 is effective, the design of which is shown and described in more detail in the following FIGS. 3-6. This swirl generator 100 is a conical structure which is acted upon tangentially several times by a tangentially flowing combustion air flow 115. The flow formed here is seamlessly transferred to a transition piece 200 using a transition geometry provided downstream of the swirl generator 100, in such a way that no separation areas can occur there. The configuration of this transition geometry is described in more detail in FIG. 6. This transition piece 200 is extended on the outflow side of the transition geometry by a mixing tube 20, both parts forming the actual mixing section 220. Of course, the mixing section 220 can consist of a single piece, that is to say then that the transition piece 200 and the mixing tube 20 merge into a single coherent structure, the characteristics of each part being retained. If the transition piece 200 and the mixing tube 20 are made of two parts, these are connected by a bushing ring 10, the same bushing ring 10 serving as an anchoring surface for the swirl generator 100 on the head side. Such a bushing ring 10 also has the advantage that different mixing tubes can be used. On the outflow side of the mixing tube 20 there is the actual combustion chamber 30 of a combustion chamber, which here is only symbolized by a flame tube. The mixing section 220 largely fulfills the task of providing a defined section downstream of the swirl generator 100, in which a perfect premixing of fuels of different types can be achieved. This mixing section, i.e. the mixing pipe 20 in the foreground, furthermore enables loss-free flow guidance, so that no backflow zone or backflow bubble can initially form even in operative connection with the transition geometry, which means that the length of the mixing section 220 can influence the quality of the mixture for all types of fuel , However, this mixing section 220 has yet another property, which consists in that the axial velocity profile itself has a pronounced maximum on the axis, so that the flame cannot be re-ignited from the combustion chamber. However, it is correct that with such a configuration this axial velocity drops towards the wall. To prevent re-ignition in this area, the mixing tube 20 is provided in the flow and circumferential direction with a number of regularly or irregularly distributed bores 21 of various cross-sections and directions through which an amount of air flows into the interior of the mixing tube 20 and along the wall in the In the sense of filming, induce an increase in the flow rate. These bores 21 can also be designed such that at least one additional effusion cooling is established on the inner wall of the mixing tube 20. Another possibility of increasing the speed of the mixture within the mixing tube 20 is to narrow its flow cross-section on the outflow side of the transition channels 201, which form the transition geometry already mentioned, as a result of which the overall speed level within the mixing tube 20 is increased. In the figure, these bores 21 run at an acute angle with respect to the burner axis 60. Furthermore, the outlet of the transition channels 201 corresponds to the narrowest flow cross-section of the mixing tube 20. The transition channels 201 mentioned therefore bridge the respective cross-sectional difference without adversely affecting the flow formed. If the selected precaution triggers an intolerable pressure loss when guiding the pipe flow 40 along the mixing pipe 20, this can be remedied by providing a diffuser (not shown in the figure) at the end of this mixing pipe. A combustion chamber 30 (combustion chamber) then adjoins the end of the mixing tube 20, a cross-sectional jump formed by a burner front 70 being present between the two flow cross sections. Only here does a central flame front form with a backflow zone 50 which has the properties of a disembodied flame holder compared to the flame front. If a flow-like edge zone forms in this cross-sectional jump during operation, in which vortex detachments occur due to the prevailing negative pressure, this leads to increased ring stabilization of the return flow zone 50. It should also be mentioned that the generation of a stable return flow zone 50 is also sufficiently high Twist number in a pipe required. If this is initially undesirable, stable backflow zones can be created by supplying small, strongly swirled air flows at the pipe end, for example by means of tangential openings. It is assumed here that the amount of air required for this is about 5-20% of the total amount of air. With regard to the design of the burner front 70 at the end of the mixing tube 20 for stabilizing the backflow zone or backflow bladder 50, reference is made to the description under FIG. 8.
A pilot burner system 300 is provided concentrically with the mixing tube 20 in the area of its outlet. This consists of an inner annular chamber 301 into which a fuel, preferably a gaseous fuel 303, flows. In addition to this inner annular chamber 301, there is a second annular chamber 302 into which an air quantity 304 flows. Both ring chambers 301, 302 have individually designed through openings, such that the individual media 303, 304 flow into a common downstream ring chamber 308 due to their function. The transfer of the gaseous fuel 303 from the annular chamber 301 into the downstream annular chamber 308 is accomplished by a number of openings 309 arranged in the circumferential direction. The passage geometry of these openings 309 is designed such that the gaseous fuel 303 flows into the downstream annular chamber 308 with a large mixing potential. The other annular chamber 302 closes with a perforated plate 305, the bores 310 provided here being designed in such a way that the air volume 304 flowing through there impacts cooling on the base plate 307 of the downstream annular chamber 308. This base plate has the function of a heat protection plate against the calorific load from the combustion chamber 30, so that this impingement cooling must be extremely efficient here. After cooling, this air mixes within this annular chamber 308 with the gaseous fuel 303 flowing in from the openings 309 of the upstream annular chamber 301 before this mixture then flows out into the combustion chamber 30 through a number of bores 306 arranged on the combustion chamber side. The mixture flowing out burns as a premixed diffusion flame with minimized pollutant emissions and accordingly forms a pilot burner acting in the combustion chamber 30 per bore 306, which ensures stable operation.

An ignition device becomes through the air-circulating ring chamber 302 311 passed through, which in the downstream annular chamber 308 Ignition of the mixture formed there. For one thing, it takes for this passage of the ignition device 311 no further constructive Measures, and on the other hand, this ignition device 311 is constantly by the air 304 flowing there is cooled anyway. This is very important because when using it temperature of approx. 1000 ° C can be reached with a glow plug. However, since there is only a low voltage for the operation proposed here, high current is required, the susceptibility of the ignition device is therefore eliminated against condensation water. Due to the arrangement of the glow plug, the use of a spark plug is also possible within of the burner, the respective ignition device 311 is thermally slightly loaded, which means that no additional cooling is required and leakages are also eliminated avoided.

Fig. 2 shows a schematic view of the burner according to Fig. 1, here in particular the flushing of a centrally arranged fuel nozzle 103 and the effect of fuel injectors 170 is pointed out. The mode of action the remaining main components of the burner, namely swirl generator 100 and transition piece 200 are closer under the following figures described. The fuel nozzle 103 is spaced with a ring 190 encased in which a number of circumferentially bored holes 161 are placed, through which an amount of air 160 into an annular chamber 180 flows and carries out the flushing of the fuel lance there. These holes 161 are slanted forward so that it is appropriate axial component arises on the burner axis 60. In active connection with these Additional fuel injectors 170 are provided in holes 161 a certain amount, preferably a gaseous fuel, into the Enter the respective amount of air 160 in such a way that a sets uniform fuel concentration 150 over the flow cross-section, as the representation in the figure symbolizes. Exactly this even Fuel concentration 150, especially the strong concentration the burner axis 60 ensures that the flame front is stabilized at the output of the burner, which causes combustion chamber pulsations be avoided.

In order to better understand the structure of the swirl generator 100, it is advantageous to if at least FIG. 4 is used at the same time as FIG. 3. Hereinafter 3 is referred to the other figures as necessary in the description of FIG.

The first part of the burner according to FIG. 1 forms the swirl generator shown in FIG. 3 100. This consists of two hollow conical partial bodies 101, 102, which are nested in a staggered manner. The number of conical Partial body can of course be larger than two, like the figures 5 and 6 show; this depends in each case, as will be explained in more detail below will depend on the operating mode of the entire burner. It is with certain Operating constellations are not excluded, one from a single spiral to provide existing swirl generator. The offset of the respective central axis or longitudinal symmetry axes 101b, 102b (cf. FIG. 4) of the conical partial bodies 101, 102 creates each other in the adjacent wall, in mirror image Arrangement, each a tangential channel, i.e. an air inlet slot 119, 120 (see FIG. 4), through which the combustion air 115 in the interior of the swirl generator 100, i.e. flows into the cone cavity 114 of the same. The cone shape the partial body 101, 102 shown in the flow direction has a certain one fixed angle. Of course, depending on the operational use, the partial bodies can 101, 102 an increasing or decreasing cone inclination in the flow direction have, similar to a trumpet. Tulip. The latter two Shapes are not recorded in the drawing, as they are without for the specialist are further sensitive. The two conical partial bodies 101, 102 have each have a cylindrical annular starting part 101a. In the area of this cylindrical Initially, the fuel nozzle 103 already mentioned under FIG. 2 is housed, which is preferably operated with a liquid fuel 112 becomes. The injection 104 of this fuel 112 coincides with the narrowest Cross-section of the conical cavity formed by the conical partial bodies 101, 102 114 together. The injection capacity and the type of this fuel nozzle 103 depends on the specified parameters of the respective burner. The conical sub-bodies 101, 102 each have a fuel line 108, 109 which run along the tangential air inlet slots 119, 120 arranged and provided with injection openings 117, through which preferably a gaseous fuel 113 in the combustion air flowing through there 115 is injected, as the arrows 116 want to symbolize. These fuel lines 108, 109 are preferably at the end of the latest tangential inflow, before entering the cone cavity 114, arranged this to get an optimal air / fuel mixture. With the by Fuel nozzle 103 brought fuel 112 is, as mentioned, normally a liquid fuel, whereby a mixture formation with a other medium, for example with a recirculated flue gas, without further is possible. This fuel 112 is preferably very low acute angle injected into the cone cavity 114. From the fuel nozzle 103 A conical fuel spray 105 is thus formed, which flows in from the tangential one rotating combustion air 115 is enclosed and degraded. The concentration of the injected fuel is then in the axial direction 112 continuously through the incoming combustion air 115 for mixing Degraded towards evaporation. If a gaseous fuel 113 Introduced via the opening nozzles 117, the fuel / air mixture is formed directly at the end of the air inlet slots 119, 120. Is the combustion air 115 additionally preheated, or for example with a recirculated Flue gas or exhaust gas enriched, so this sustainably supports the Evaporation of the liquid fuel 112 before this mixture in the downstream Stage flows, here in the transition piece 200 (see FIGS. 1 and 7). The The same considerations also apply if liquid lines 108, 109 Fuels should be supplied. When designing the tapered partial body 101, 102 with regard to the cone angle and the width of the tangential air inlet slots 119, 120 are strict limits to be observed so that the desired Flow field of the combustion air 115 at the exit of the swirl generator 100 can set. Generally speaking, a downsizing of the tangential air inlet slots 119, 120 the faster formation of a backflow zone already favored in the area of the swirl generator. The axial speed Within the swirl generator 100, a corresponding one shown in FIG (Item 160) Increase or stabilize the supply of an air quantity described in more detail. A corresponding swirl generation in operative connection with the downstream one Transition piece 200 (see FIGS. 1 and 7) prevents the formation of Flow separations within the swirl generator 100 downstream Mixing tube. The construction of the swirl generator 100 is furthermore particularly suitable, change the size of the tangential air inlet slots 119, 120, which is a relatively large one without changing the overall length of the swirl generator 100 operational bandwidth can be captured. Of course, the partial bodies 101, 102 can also be moved relative to one another in another plane, which even an overlap of the same can be provided. It is further possible, the sub-bodies 101, 102 by a counter-rotating movement spiral to nest into each other. So it is possible, the shape, the size and the configuration of the tangential air inlet slots 119, 120 arbitrarily vary, with which the swirl generator 100 is universal without changing its overall length can be used.

4 shows, among other things, the geometric configuration of optional ones Baffles 121a, 121b. They have a flow introduction function. which, according to their length, the respective end of the tapered Partial bodies 101, 102 in the flow direction with respect to the combustion air 115 extend. Channeling the combustion air 115 into the cone cavity 114 can be opened or closed by one of the baffles 121a, 121b Area of entry of this channel into the cone cavity 114 placed fulcrum 123 can be optimized, especially if the original Gap size of the tangential air inlet slots 119, 120 changed dynamically should be, for example, to change the speed of the combustion air 115 to achieve. Of course, these can be dynamic Precautions can also be provided statically by using baffles as needed form a fixed component with the tapered partial bodies 101, 102.

5 shows that the swirl generator 100 now consists of four partial bodies 130, 131, 132, 133 is constructed. The associated longitudinal symmetry axes for each sub-body are marked with the letter a. To this Configuration is to be said that it is due to the lower generated with it Twist strength and in cooperation with a correspondingly enlarged Slot width is best suited, the bursting of the vortex flow on the downstream side to prevent the swirl generator in the mixing tube, thus causing the mixing tube to can fulfill the intended role.

FIG. 6 differs from FIG. 5 in that the partial bodies 140 here 141, 142, 143 have a blade profile shape which is used to provide a certain Flow is provided. Otherwise, the mode of operation of the swirl generator stayed the same. The admixture of fuel 116 in the combustion air flow 115 happens from inside the blade profiles, i.e. the fuel line 108 is now integrated in the individual blades. Here, too, are the longitudinal axes of symmetry to the individual partial bodies with the Letter a marked.

7 shows the transition piece 200 in a three-dimensional view. The transition geometry is corresponding for a swirl generator 100 with four partial bodies 5 or 6, built. Accordingly, the transition geometry as a natural extension of the upstream partial bodies, four transition channels 201 on, whereby the conical quarter area of said partial body is extended until it cuts the wall of the mixing tube. The same considerations also apply if the swirl generator is based on a principle other than the one below Fig. 3 is constructed. The down in the flow direction running surface of the individual transition channels 201 has a flow direction spiral shape, which has a crescent shape Course describes, corresponding to the fact that the flow cross-section is present of the transition piece 200 flared in the flow direction. The swirl angle of the transition channels 201 in the flow direction is selected so that that the pipe flow then up to the cross-sectional jump on Combustion chamber entry still has a sufficient distance to be perfect Premix with the injected fuel. Further increases the axial speed due to the above-mentioned measures on the mixing tube wall downstream of the swirl generator. The transition geometry and the measures in the area of the mixing tube cause a significant increase the axial velocity profile towards the center of the mixing tube, see above that the danger of early ignition is decisively counteracted.

8 shows the tear-off edge already mentioned, which emerges at the burner outlet is formed. The flow cross section of the tube 20 receives one in this area Transition radius R, the size of which basically depends on the flow within of the tube 20 depends. This radius R is chosen so that the Applies flow to the wall and so the swirl number increases sharply. Quantitatively the size of the radius R can be defined so that it is> 10% of the inside diameter d of the tube is 20. Opposite a flow without a radius Now the backflow bladder 50 increases enormously. This radius R runs to the exit plane of the tube 20, the angle β between the beginning and end of curvature is <90 °. Along one leg of the angle β the tear-off edge A runs inside the tube 20 and thus forms a tear-off step S opposite the front point of the tear-off edge A, whose depth> 3 mm is. Of course, this can be parallel to the exit plane of the tube 20 running edge based on a curved course back to the exit level to be brought. The angle β ', which is between the tangent of the tear-off edge A and perpendicular to the exit plane of the tube 20 is the same size like angle β. The advantages of this formation of this tear-off edge come from EP-0 780 629 A2 under the chapter "Presentation of the invention". Another Design of the tear-off edge for the same purpose can be done with the combustion chamber achieve toroidal notches. This publication is inclusive the scope of protection there regarding the tear-off edge is an integrating one Part of this description.

LIST OF REFERENCE NUMBERS

10

jack ring

20

Mixing tube, part of the mixing section 220

21

Holes, openings

30

Combustion chamber, combustion chamber

40

Flow, pipe flow in the mixing pipe, main flow

50

Backflow zone, backflow bubble

60

Brenner

100

swirl generator

101, 102

Partial conical body

101 a

Annular initial part

101b, 102b

Longitudinal axes of symmetry

103

fuel nozzle

104

fuel injection

105

Fuel spray (fuel injection profile)

108, 109

fuel lines

112

Liquid fuel

113

Gaseous fuel

114

Kegethohlraum

115

Combustion air (combustion air flow)

116

Fuel injection from lines 108, 109

117

fuel nozzles

119, 120

Tangential air inlet slots

121a, 121b

baffles

123

Pivot point of the guide plates

130, 131, 132, 133

partial body

131a, 131a, 132a, 133a

Longitudinal axes of symmetry

140, 141, 142, 143

Vane-shaped partial body

140a, 141a, 142a, 143a

Longitudinal axes of symmetry

150

fuel concentration

160

Air volume, mixed air

161

Holes, openings

170

Fuel injectors

180

Annular air chamber

190

ring

200

Transition piece, part of the mixing section 220

201

Transition passages

220

mixing section

300

Pilot burner system

301

Inner ring chamber

302

Secondary ring chamber

303

Gaseous fuel

304

air flow

305

Perforated plate

306

Drilling in the combustion chamber, pilot burner

307

Heat Shield

308

Downstream ring chamber

309

Openings of the inner ring chamber

310

Holes for impingement cooling of the heat protection plate

311

detonator

Claims (20)

1. Burner for operating a heat generator, the burner essentially comprising a swirl generator (100) for a combustion-air flow and means for injecting at least one fuel into the combustion-air flow, a mixing section (220) being arranged downstream of the swirl generator and having, inside a first part of the section in the direction of flow, a number of transition passages (201) for passing a flow formed in the swirl generator into a mixing tube (20) arranged downstream of these transition passages, characterized in that a cooled pilot-burner system (300) is arranged in the lower region of the mixing tube (20) in such a way as to act in a combustion space (30) arranged downstream of the mixing tube (20), and in that at least one ignition device (311) is integrated in the pilot-burner system (300).
2. Burner according to Claim 1, characterized in that the pilot-burner system (300) comprises at least two media-carrying chambers (301, 302) and a further common chamber (308) arranged downstream, in that the media (303, 304) from the other two chambers (301, 302) can be mixed in this chamber (308) arranged downstream, and in that the chamber (308) arranged downstream has means for forming pilot burners (306) which act in the combustion space (30) and can be operated by the mixture of the two media (303, 304).
3. Burner according to Claims 1 and 2, characterized in that the media-carrying chambers (301, 303) are of annular and juxtaposed design, in that a gaseous fuel (303) flows through the first annular chamber (301) and an air quantity (304) flows through the second annular chamber (302), in that fitted in the second annular chamber (302) are means (305) which enable the air (304) flowing there to bring about impingement cooling on a heat-shield plate (307) arranged at the end of the pilot-burner system (300), and in that the ignition device (311) is directed into position through the second annular chamber (302).
4. Burner according to Claim 3, characterized in that the means for forming the impingement cooling is a perforated plate (305) forming a base in the juxtaposed annular chamber (302).
5. Burner according to Claim 1, characterized in that the means comprise a ring (190) arranged on the head side of the swirl generator (100) and in interaction with a fuel nozzle (103), in that this ring (190) has a number of bores (161) arranged in the peripheral direction, and in that a fuel (170) can be injected into an air quantity (160) flowing through the bores (161).
6. Burner according to Claim 5, characterized in that the bores (161) are directed so as to slant forwards.
7. Burner according to Claim 5, characterized in that the fuel nozzle (103) is surrounded by an annular air chamber (180).
8. Burner according to Claim 1, characterized in that the burner front of the mixing tube (20) towards the combustion space (30) arranged downstream is formed with a breakaway edge (A).
9. Burner according to Claim 1, characterized in that the number of transition passages (201) in the mixing section (220) corresponds to the number of partial flows formed by the swirl generator (100).
10. Burner according to Claim 1, characterized in that the mixing tube (20) arranged downstream of the transition passages (201) is provided with openings (21) in the direction of flow and in the peripheral direction for injecting an air flow into the interior of the mixing tube (20).
11. Burner according to Claim 10, characterized in that the openings (21) run at an acute angle relative to the burner axis (60) of the mixing tube (20).
12. Burner according to Claim 1, characterized in that the cross section of flow of the mixing tube (20) downstream of the transition passages (201) is less than, equal to or greater than the cross section of the flow (40) formed in the swirl generator (100, 100a).
13. Burner according to Claim 1, characterized in that a combustion chamber (30) is arranged downstream of the mixing section (220), in that there is a jump in cross section between the mixing section (220) and the combustion chamber (30), which jump in cross section induces the initial cross section of flow of the combustion chamber (30), and in that a backflow zone (50) can take effect in the region of this jump in cross section.
14. Burner according to Claim 1, characterized in that there is a diffuser and/or a venturi section upstream of the burner front (70).
15. Burner according to Claim 1, characterized in that the swirl generator (100) consists of at least two hollow, conical sectional bodies (101, 102; 130, 131, 132, 133; 140, 141, 142, 143) which are nested one inside the other in the direction of flow, in that the respective longitudinal symmetry axes (101b, 102b; 130a, 131a, 132a, 133a; 140a, 141a, 142a, 143a) of these sectional bodies run mutually offset in such a way that the adjacent walls of the sectional bodies form ducts (119, 120), tangential in their longitudinal extent, for a combustion-air flow (115), and in that at least one fuel nozzle (103 [lacuna] can take effect in the interior space (114) formed by the sectional bodies.
16. Burner according to claim 15, characterized in that further fuel nozzles (117) are arranged in the region of the tangential ducts (119, 120) in their longitudinal extent.
17. Burner according to Claim 15, characterized in that the sectional bodies (140, 141, 142, 143) have a blade-shaped profile in cross section.
18. Burner according to Claim 15, characterized in that the sectional bodies have a fixed cone angle, increasing conicity, or decreasing conicity in the direction of flow.
19. Burner according to Claim 15, characterized in that the sectional bodies are nested spirally one inside the other.
20. Burner according to Claim 1, characterized in that the ignition device (311) is an incandescent ignition pin or a spark plug.

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