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
  • F23R3/28—Continuous combustion chambers using liquid or gaseous fuel characterised by the fuel supply
  • F23R3/283—Attaching or cooling of fuel injecting means including supports for fuel injectors, stems, or lances
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
  • F23D—BURNERS
  • F23D2211/00—Thermal dilatation prevention or compensation
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
  • F23D—BURNERS
  • F23D2900/00—Special features of, or arrangements for burners using fluid fuels or solid fuels suspended in a carrier gas
  • F23D2900/00018—Means for protecting parts of the burner, e.g. ceramic lining outside of the flame tube

Definitions

• the invention relates to a burner assembly for fluid fuels and a method of manufacturing a burner assembly.
• Gas turbine engines are used in power plants and other large-scale engine applications, among other things, with burner assemblies for firing fluid fuels.
• burner assemblies for firing fluid fuels.
• so-called dual-fuel burners are used, which are provided for the combustion of liquid and gaseous fuels, for example natural gas and fuel oil, optionally or in combination.
• the burner assemblies are accordingly large in size and have a complex structure with multiple fuel supply channels.
• a centrally arranged small dimensioned pilot burner with its own
• the large main burner ⁇ Namely mainly operated in the lean mixture operation with excess oxygen, thereby achieving more favorable emissions.
• the operation with a lean mixture leads to the fact that the flame of the main burner at least ⁇ in certain Bet ⁇ ebsSearchen subject to fluctuations, which are compensated by a continuously igniting effect of the pilot burner.
• Such a burner arrangement is reproduced, for example, in EP 0 580 683 B1.
• a challenge with these burners is the mechanical stresses, which are caused by an uneven thermal distribution, in the walls of the metallic housing, the so-called hub, in which the supply ducts of the gas and oil energy storage are arranged relatively close to one another.
• a gas ring space feeds the main burner on the upstream side of the flow direction of the incoming air upstream of the so-called swirl blades, which mediate the air ⁇ stream with the fuel gas a mixing swirl, or through the swirl blades through.
• an oil supply is present, which is usually arranged closer to the burner output m, as the gas supply. It comprises an oil space and an oil feed channel leading to the annular space, which is arranged in the hub wall located between the gas ring space and the pilot burner.
• gas Since gas has a lower density than oil, it requires a larger cross-section, whereby the dimensioning of the gas supply is much greater than the oil feed. Therefore, the part of the burner hub with the gas supply has a larger outer surface facing the air duct than the oil supply. Air is supplied with precompressed air that has passed through a compressor, whereby these conces- led air due to the compression to a temperature ⁇ has the already reached more than 400 ° C. Consequently, the area of the burner hub with the gas supply is heated rapidly to a temperature in the range of over 400 0 C and remains at this operating temperature. The leading to Ol ⁇ ngraum Olzubuchkanal is, however, further away from the hot Lucaszubuchka ⁇ nal so that the oil in the oil supply channel hardly experience a hike and therefore only has a temperature of about 50 0 C.
• the burner hub Since, on the one hand, the burner hub experiences strong heating in the area of the gas ring space and, on the other hand, the adjacent oil supply channel is considerably cooler, the wall between the gas ring space and the oil supply channel is subject to a large temperature gradient. As a result of the temperature gradient, thermal stresses occur which shorten the service life of such burner hubs or necessitate the use of a high-quality material with the associated costs. Also in other areas, where a cold fuel is led through a hot hub area, such stresses occur.
• the present invention therefore has the object to reduce the described thermal stresses in the burner hub of the burner assembly.
• a burner arrangement according to the invention for a combustion plant for firing fluid fuels comprises a burner hub, an air supply system surrounding the burner hub and at least one fuel supply channel with fuel outlets leading in the direction of the air supply system.
• the at least one fuel supply channel is at least partially in the burner -Nabe formed so that the material of the burner hub forms a wall of the fuel supply channel.
• Disposed within at least one fuel supply passageway is a shield wall spaced from the wall of the fuel supply passageway so that a space not belonging to the flow path of the fuel passing through the fuel supply passageway is formed between the wall of the fuel supply passageway and the shielding wall.
• the shielding wall is designed as a hollow body introduced into the fuel feed channel and adapted to the inner contour of the fuel feed channel.
• the interspace forms a poorly warm conductive area in comparison to the surrounding metal of the burner hub, which thermally insulates the metal of the hub from the flowing fuel and thus limits the heat exchange between the fuel and the burner hub. Due to the reduced heat exchange, the thermally induced stresses decrease in comparison to burner arrangements without shielding wall.
• the adaptation to the inner contour of the fuel supply channel allows it is to ensure a uniform space between the wall of the fuel supply channel and the shield.
• the fuel feed channel may comprise, in particular, a distributor channel leading to the fuel outlet openings and a substantially annular distributor channel and a substantially tubular inlet channel leading to the distributor channel.
• the hollow body for example, is designed as a sleeve or as a hollow torus.
• the hollow body is preferably formed at least partially of metal or ceramic.
• the hollow body can in principle be emstuckig or multi-part design.
• Em formed of metal hollow body may, for example, at least partially as a bent sheet metal part or at least partially as a machined metal part, such as a rotating part, be formed.
• the hollow body can be provided with Aust ⁇ ttsvorsprungen which are introduced into the respective fuel outlet openings of the fuel supply channel, so that penetration of fuel into the gap at the transition between the Ver ⁇ divider and the Brennstoffaustrittso réelleen can be avoided.
• the hollow body may be provided with at least one Emt ⁇ ttsan gleich which is introduced m a Eint ⁇ tts- opening of the fuel supply channel in order to prevent penetration of fuel into the gap at the transition between the supply channel and the distribution channel.
• the projections can also serve as positioning means which hold the hollow body in the fuel channel in the correct position.
• the fuel supply passage comprises an m the wall of the burner hub disposed, leading to the Brennstoffaustrittso réelleen and at least partially wise annular fuel distribution channel.
• the ⁇ ser is formed of two with the open sides opposite each other ⁇ horizontally arranged grooves.
• the burner hub comprises at least a first and a second hub part, which are grooved together.
• a parting plane between the first and the second boss part proceeds in such a way by the Brennstoffvertei ⁇ lerkanal the respective fuel supply channel that, before the joining together of the two hub parts in each hub part in each case one of the fuel distribution passage forming grooves is present and the hollow body is positioned in one of the grooves.
• the first and the second hub part and possibly further hub parts of the burner hub can be connected to each other in terms of force, form or material, for example by welding, lacing, screwing or riveting.
• said object is achieved by a method for producing the burner hub according to the described particular embodiment of the burner assembly by a) at least one hollow body m the groove forming part of the fuel supply channel in a first or second hub part the burner hub is installed, b) the first and the second hub part of the burner hub ent ⁇ long the parting plane are joined together, and c) between the first and second hub part of the burner hub created a positive, positive or material connection For example, by welding, soldering, screwing or riveting.
• the method according to the invention makes it possible to produce a burner hub with a shielding wall in an annular fuel distributor channel, wherein the shielding wall is designed as a hollow body introduced into the fuel distributor channel.
• the method can in particular also be applied to a burner hub with more than two hub parts.
• another hollow body is installed in the groove forming part of a fuel supply groove in a further hub part of the burner hub.
• FIG. 1 shows a burner arrangement known from EP 0 580 683 B1
• FIG. 2 shows a known embodiment of the burner hub of a burner arrangement
• FIG. 3 shows a schematically exaggerated sequence of the thermally induced stresses in the burner hub according to the prior art from FIG. 2,
• FIG. 4 shows a first embodiment of the burner hub
• Figure 5 shows a second embodiment of the burner hub
• FIG. 6 shows a perspective view of a hollow body for an annular fuel distributor channel.
• FIG. 1 shows a burner arrangement according to the prior art, which can optionally be used in conjunction with a plurality of similar arrangements, for example in the combustion chamber of a gas turbine plant. It consists of an inner part, the pilot burner system and a concentric outer part, the main burner system. Both systems are suitable for operation with gaseous and / or liquid fuels in any combination.
• the pilot burner system comprises a central oil supply 1 (Medium G) having a ⁇ arranged at its end Olduse 5 and a concentrically arranged around the central oil supply 1 around inner gas supply channel 2 (Medium F). This in turn is surrounded by a concentrically arranged around the axis of the burner inner air supply channel.
• 3 shows a burner arrangement according to the prior art, which can optionally be used in conjunction with a plurality of similar arrangements, for example in the combustion chamber of a gas turbine plant. It consists of an inner part, the pilot burner system and a concentric outer part, the main burner system. Both systems are suitable for operation with gaseous and
• a suitable ignition system may be arranged in or on the inner air supply channel 3, for which many embodiments are known and whose illustration has therefore been omitted here.
• the inner air supply channel 3 has a swirl blading 6 in its end region.
• the pilot burner system can operate in a manner known per se, i. H. predominantly as a diffusion burner operated. Its task is to maintain the main burner in a stable burning operation, since it is usually operated with a lean mixture to reduce the emission of pollutants, which requires stabilizing its flame by means of a diffusion flame or a flame based on a less lean mixture.
• the main burner system has a concentric with the pilot burner system arranged and obliquely on this incoming outer air supply Rmgkanalsystem 4.
• This air supply ring channel system 4 is also provided with a swirl blading 7.
• the swirl blading 7 consists of hollow blades with outlet nozzles 11 in the flow cross section of the air supply annular channel system 4 (medium A). These are fed from a Gaszu ⁇ conduit 19 and a gas ring channel 9 through openings 10.
• the burner has an oil supply channel 23, which opens into an oil channel 13, which in turn has outlet nozzles 14 in the region or downstream of the swirl blading 7.
• Figure 2 shows an embodiment of the burner hub 18 of a burner assembly according to the prior art in cross section. In the burner hub 18 are a gas ring space 9 and an Ol ⁇ ngraum
• annular cavities 9 and 13 arranged on the outwardly facing and tapered side surface of the burner hub 18, the annular cavities 9 and 13 each have a multiplicity of outlet openings 10 and 10
• FIG. 3 shows a schematically exaggerated sequence of the thermally induced stresses in the burner hub according to the prior art from FIG. Due to the stresses, the wall 21 between the gas annulus 9 and the Olzu effetskanal 23 is deformed. This deformation of the metallic see burner hub 18 is due to the temperature gradient in the wall between the Olzu effetskanal 23, flows through the oil at a temperature of about 50 0 C, and the gas annulus 9, due to the heating by the compressor air in Air supply channel 4 (medium A in Fig.l) is heated to about 420 ° C.
• FIG. 4 shows a detail of a cross section through an embodiment of the inventive burner assembly.
• the burner assembly comprises a burner hub 18, in which a gas annulus 9 with a gas supply channel 19 (not shown in Figure 4) and a Ol ⁇ ngraum 13 are arranged with an Olzu effetal 23.
• the basic structure of the burner assembly corresponds to the structure described with reference to Figures 1 and 2. Therefore, only the differences from the burner construction described in FIGS. 1 and 2 will be described.
• a shielding wall 30 is arranged in the oil supply duct 23 such that a gap 38 is formed between the wall 21 between the gas ring space 9 and the oil supply duct 23 on the one hand and the shield wall 30 on the other hand.
• This intermediate space 38 insulates the one formed by the inner surface of the shielding wall 30 Stromungspfad the oil thermally from the wall 21 between the gas annulus 9 and the Olzutechnischskanal 23, since the medium in the gap, such as air or hardly or hardly flowing oil, has a much lower thermal conductivity, as the metal of the burner hub 18.
• the thermal conductivity of air amounts to 0.023 W / mK and that of oil to about 0.15 W / mK (at room temperature).
• the thermal conductivity of metals is two to three orders of magnitude higher.
• the intermediate space 38 can therefore be regarded as an adiabatically acting thermal shield.
• the amount of distance s between the wall 21 and the shielding wall 30 may be used constructively to set a desired heat transfer rate.
• Shield wall realized in the form of a sleeve inserted into the Olzu effeteal 23 30, which prevents a direct contact along the Stromungspfades Olzu effetskanal 23 stream ⁇ cold oil with the wall 21 between the gas annulus 9 and the Olzu effetskanal 23.
• the outer diameter of the sleeve 30 is dimensioned smaller by a predetermined amount than the inner diameter of the Olzu effetskanal 23, so that between the inserted sleeve 30 and the wall 21, a gap 38 is formed, in which a medium having a substantially lower thermal conductivity than the metal Burner hub 18 is located.
• the oil itself can be used, provided that no ignition to be ⁇ fear, since in this case, no sealing of the gap 38 is required against the Stromungspfad of the oil.
• the sleeve 30 easy to mount in the Olzu effetskanal 23 of Bren ⁇ ner hub 18, it is formed as an insertable into an opening in a tube-like running portion 37 of the sleeve 23 Olzu effetskanal 30th
• the sleeve 30 has for this purpose at its stromaufwartigen end on a preferential ⁇ circular encircling annular positioning projection 33 which serves as a spacer for radially centering the Hulsenkorpers in Olzu effetal 23 and at the same time carries the function of an abutment edge, which against a komplementä ⁇ re, existing abutment edge of a corresponding Nutausfrasung abuts in the region of the opening of the tubular projection 37
• the present embodiment has a further positioning projection 35, which is arranged in the vicinity of the downstream End of the sleeve 30.
• the positioning projection 35 arranged at the downstream end of the sleeve 30 is preferably designed as an annular circumferential projection and, with its preferably cylindrical outer diameter, reaches up to the wall of the cavity 38 so that it likewise contributes to the centering of the sleeve 30 ,
• FIG. 5 shows a second embodiment of the inventive burner hub 18 with a shielding wall arranged in the gas ring space 9, which is formed by a hollow body 40 inserted into the gas ring space 9.
• this is modeled on the ring shape of the annular space 9 and thereby formed itself torusformig.
• 6 shows a perspective view of the torusformigen Holkorpers 40 is provided ⁇ .
• the outer dimensions of the toroidal hollow body 40 are selected with respect to the inner dimensions of the gas annular space 9 such that an adiabatically acting intermediate space 48 is formed between the outer side of the hollow body 40 and the inner surface of the gas space 9, with which the incoming fuel gas from the walls of the Gas annulus 9 is thermally insulated.
• the toroidal hollow body 40 has a multiplicity of outlet connections 42 arranged around the circumference. As can be seen in Figure 5, these are introduced into the Brennstoffaustritts- openings 10 of the gas annulus 9 so that their outer surfaces abut the inner surfaces of the openings 10.
• the toroidal hollow body 40 has at least one outlet connection 43 which can be introduced into the gas supply duct 19 leading to the gas annular space 9 in such a way that its outer surface bears against the inner surface of the gas supply duct 19.
• these connections 42 and 43 fulfill the function of spacers, by means of which a predetermined distance is set between the walls of the gas ring space 9 and the outer surfaces of the hull projection 40 and maintained during operation.
• the gas flowing through is prevented from direct heat exchange with the surrounding areas of the burner hub 18.
• the fuel gas may have a lower temperature than the burner hub 18 heated to about 420 ° C by the pre-compressed air.
• the gas due to the thermal insulation, the
• the Holkorpers 40 is preferably designed as a thin-walled, bent sheet metal component.
• two bent to half-shell sheet metal parts can be joined and welded or pressed.
• the hollow body may also be formed as a casting, but the wall thickness caused by casting would be detrimental and would necessitate an increase in the dimensions of the burner hub 18.
• FIG. 5 also shows the sleeve 30, which is arranged in the oil supply duct 23 and projects into the oil space 13.
• a shielding wall in the form of a toroidal hollow body corresponding to the hollow body 40 may also be arranged in the gas ring space 9 in the oil space 13, so that the heat transfer between the walls of the oil space 13 and the oil can also be reduced.
• This torus-shaped hollow body, not shown, can then be connected to the end of the sleeve 30.
• the burner hub least 18 formed preferably in answers- two boss parts 1801 and 1802 so separated that the parting plane XX 9 substantially separates the Gas ⁇ ngraum symmetrical and nikum offeredd, thereby making free.
• the gas ring space 9 is then essentially formed from two grooves lying opposite one another in the abutment surfaces of the hub parts 1801 and 1802.
• the toroidal hollow body 40 can be inserted into the groove of one of the two hub parts 1801 and 1802 and fixed there.
• the joining of the hub parts 1801 and 1802 can thereafter force, shape or cohesive, preferably by Ver ⁇ welding, riveting or screwing done.
• the burner hub 18 can have a further division along the separating surface YY for this purpose.
• the burner hub 18 in this case includes a third hub portion 1803 which is essentially separated by the separation plane YY, the space the Ol ⁇ ng- 13 symmetrically and nikum offeredd on ⁇ , thereby making accessible, is separated from the previously disposed hub portion 1802nd
• the Ol ⁇ ngraum 13 is then also formed essentially of two m the abutting surfaces of the hub parts 1802 and 1803 opposing grooves.
• the torus-shaped hollow body can be installed by inserting the toroidal hollow body into the groove of one of the two hub parts 1802 and 1804 and fixing it there before the two hub parts 1802 and 1803 are joined together.
• the Hullenvor ⁇ chtung 40 can be secured in this case also with the discharge port 43 at the projecting into the Ol ⁇ ngraum end of the sleeve 30.

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• Engineering & Computer Science (AREA)
• Chemical & Material Sciences (AREA)
• Combustion & Propulsion (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Gas Burners (AREA)
• Nozzles For Spraying Of Liquid Fuel (AREA)

Priority Applications (1)

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ID=40957759

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• 2009
  • 2009-03-17 EP EP09155348A patent/EP2236933A1/fr not_active Withdrawn
  • 2009-11-27 AT AT09764490T patent/ATE527496T1/de active
  • 2009-11-27 EP EP09764490A patent/EP2271876B1/fr not_active Not-in-force
  • 2009-11-27 WO PCT/EP2009/065983 patent/WO2010105707A1/fr not_active Ceased

Non-Patent Citations (1)

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