US20190093893A1

US20190093893A1 - Combustion chamber assembly comprising thermal shield and burner gasket as well as manufacturing method

Info

Publication number: US20190093893A1
Application number: US16/141,342
Authority: US
Inventors: Carsten Clemen; Ruud EGGELS
Original assignee: Rolls Royce Deutschland Ltd and Co KG
Current assignee: Rolls Royce Deutschland Ltd and Co KG
Priority date: 2017-09-28
Filing date: 2018-09-25
Publication date: 2019-03-28
Also published as: EP3462089B1; DE102017217330A1; EP3462089A1

Abstract

A combustion chamber assembly group includes a burner seal with a bearing section that extends along a longitudinal axis and has a passage hole for positioning a fuel nozzle at a combustion chamber of an engine, and a heat shield which, when mounted according to the intended use at the combustion chamber of the engine, is located inside the combustion space of the combustion chamber and has a passage hole through which the bearing section of the burner seal extends. The burner seal that is manufactured in an additive manner and the heat shield form a constructional unit in which the heat shield is received at least partially between a radially outwardly pointing opening edge of the burner seal and a radially outwardly extending web of the burner seal, so that any separation of the heat shield from the burner seal along the longitudinal axis is excluded.

Description

This application claims priority to German Patent Application 102017217330.0 filed Sep. 28, 2017, the entirety of which is incorporated by reference herein.
The invention in particular relates to a combustion chamber assembly group with a burner seal and a heat shield as well as to a method for manufacturing such a combustion chamber assembly group.
In a combustion chamber for an engine, in particular for a gas turbine engine, it is known to mount a fuel nozzle for injecting a fuel-air mixture into the combustion space of the combustion chamber by means of a burner seal at the combustion chamber. For this purpose, the burner seal has a bearing section that extends along a longitudinal axis and has a continuous passage hole inside of which the fuel nozzle is positioned. Further a heat shield is provided on the combustion space side, which is located inside the combustion space when mounted according to the intended use at the combustion chamber of the engine and which has a passage hole through which the bearing section of the burner seal extends. At that, the bearing section of the burner seal projects through the passage hole of the heat shield with an opening edge, so that the opening edge of the burner seal, which points radially outwards with respect to the longitudinal axis and thus widens in the axial direction, is positioned behind the heat shield. The opening angles and diameters of the opening edge at the end of the passage hole are limited by the heat shield having to be pushed over the opening edge as the combustion chamber assembly group is being mounted at the combustion chamber. Thus, the combustion chamber seal is usually arranged at the combustion chamber, e.g. at a head plate of the combustion chamber, from the side of the combustion space before the heat shield is subsequently attached to affix the combustion chamber assembly group at the combustion chamber.
Even though it would be advantageous with in view of improving the mixing of fuel and air to design the opening edge of the burner seal that is located inside the combustion space with an opening angle that is as large as possible and with a diameter that is as large as possible, this is only possible to a considerably restricted degree with regards to the necessary heat shield. Accordingly, in the combustion chamber assembly groups as they are known from the state of the art, the mixing in the primary zone can be improved only to a certain extent by means of a constructive adjustment of the opening edge of the burner seal.
Thus, there is the need for a combustion chamber assembly group for an engine, in particular for a gas turbine engine, that is improved in this regard.
This objective is achieved through a combustion chamber assembly group according to claim 1 as well as through a manufacturing method according to claim 19.
What is proposed according to a first aspect is a combustion chamber assembly group that comprises at least the following:

- a burner seal with a bearing section that extends along a longitudinal axis and has a passage hole (extending along this longitudinal axis) for positioning a fuel nozzle at a combustion chamber of an engine, wherein
  - (a) at one end of the passage hole, the bearing section has an opening edge that points radially outward with respect to the longitudinal axis (and thus widens in the axial direction) and that is located inside a combustion space of the combustion chamber when mounted according to the intended use at the combustion chamber of the engine, and
  - (b) at least one web extending radially outwards with respect to the longitudinal axis is formed at the bearing section,
  - and
- a heat shield that is located inside the combustion space of the combustion chamber when mounted according to the intended use at the combustion chamber of the engine and that has a passage hole through which the bearing section of the burner seal extends.

According to the invention, the burner seal and the heat shield form a constructional unit which is manufactured in an additive manner and in which the heat shield is at least partially received between the radially outward pointing opening edge and the at least one radially outwardly extending web, so that a (non-destructive) separation of the heat shield from the burner seal along the longitudinal axis is excluded.
Thus, the burner seal and the heat shield form an integral constructional unit that is to be manufactured in advance and that is to be mounted to a combustion chamber, e.g. in the area of a head plate of the combustion chamber, with the heat shield not being mountable independently of the burner seal. Rather, the heat shield is supported at the burner seal between the opening edge formed by the burner seal and the at least one web formed by the burner seal and extending radially outwards, so that the heat shield cannot be removed without destroying the burner seal. Thus, the heat shield cannot be displaced relative to the burner seal over the opening edge or the web along the longitudinal axis.
Due to the fact that the heat shield and the burner seal form an integral constructional unit, in which the heat shield is received between the two radially projecting sections of the burner seal (opening edge and web), so that a non-destructive separation of the two components from each other is not possible, the issue of a subsequent mounting of the heat shield at the burner seal no longer arises. The design of the opening edge and in particular of its opening angle and its diameter are no longer limited by the fact that the heat shield has to be pushed over the opening edge with its passage hole. By providing a prefabricated constructional unit of burner seal and heat shield, in which the two previously mentioned components cannot be separated from each other in a non-destructive manner, mounting of these components at the combustion chamber is also facilitated.
The burner seal and the heat shield are manufactured in an additive manner in a joint manufacturing process, for example by being built up layer by layer, so that it is no longer necessary to observe any requirements regarding the mountability of the heat shield at the burner seal. In one embodiment variant, it is provided that the constructional unit of burner seal and heat shield is manufactured in an additive manner by means of a laser sintering method.
In one embodiment variant, it is provided that the burner seal is floatingly mounted at the heat shield. Although the burner seal and the heat shield form an (integral) constructional unit, in this embodiment variant the burner seal is accordingly still supported in such a way that it is at least axially displaceable relative to the heat shield. In this manner, an axial displacement of the burner seal relative to the heat shield affixed at the combustion chamber is still possible during operation of the engine. The floating mounting of the burner seal at the heat shield can further also include that the burner seal is supported at the heat shield in a radially displaceable manner with respect to the longitudinal axis of the bearing section.
In one embodiment variant, due to the radially outwards directed opening edge, the passage hole of the burner seal has a diameter at its end that is located (in the mounted state) inside the combustion space that is larger than a diameter of the passage hole in the heat shield. Thus, an (end) diameter of the opening edge is larger than a maximum diameter of the passage hole in the heat shield. If the combustion chamber assembly group is mounted at the combustion chamber, and thus in the thus defined mounted state, the burner seal—connecting to an exit opening of the fuel nozzle—thus provides an opening edge with a larger diameter than is the case or is possible in combustion chamber assembly groups that have been realized in practice so far.
In one embodiment variant, the opening edge can extend (at an axial distance to the heat shield) up to the height of a radially outermost edge of the heat shield or radially outwards beyond this radially outer edge of the heat shield. In this manner, the opening edge of the burner seal completely covers the heat shield as viewed from the combustion space along the longitudinal axis. Thus, in such a variant, the opening edge of the burner seal, which has been shifted further outwards, can at least partially take over the function of a heat shield. At that, the design and expansion of the heat shield inside the combustion space can be strongly simplified. For example, any cooling nubs, cooling ribs and/or cooling holes at the heat shield can be omitted. If necessary, it can in particular be provided in this context that the burner seal is provided with cooling air holes or an internal cooling in the area of the opening edge, in particular with cooling air holes and/or an internal cooling as they are described in DE 10 2016 212 649.0.
In one embodiment variant, the opening edge extends at an opening angle in the range of 20° to 50° with respect to the longitudinal axis of the burner seal. Thus, for an opening angle α, it for example applies that 20° a 50°. Here, an inner surface area of the passage hole that is defined by the opening edge and into which the fuel nozzle is inserted thus extends, at its end that projecting into the combustion space, at an angle of 20° to 50°, for example at an opening angle of 20°, 30°, 40° or 50°, with respect to the longitudinal axis. Here, the opening edge can continuously widen along the longitudinal axis and have a circular cross section.
In particular for saving additional components and also for a more precise positioning of the burner seal via the heat shield, the heat shield can form an embracing section, that engages around the at least one web of the burner seal extending radially outwards. Via this embracing section, the heat shield and the burner seal are thus held in a defined position to each other by at least one section of the heat shield extending beyond the radially outwards extending web of the burner seal and engaging around the same.
In a possible further development, the embracing section defines a gap inside of which the at least one web of the burner seal that extends radially outwards is at least partially received (in a form-fit manner). This gap extends for example in the shape of a circular segment or a circle about the longitudinal axis. For example, the gap can be formed as an annular gap at an embracing section of the heat shield that extends circumferentially about the longitudinal axis. In principle, the depth of the gaps can be dimensioned in such a manner that the burner seal is still radially displaceable with respect to the heat shield.
In principle, the constructional unit of burner seal and heat shield can be affixed via the heat shield at a combustion chamber component that borders the combustion space. This combustion chamber component may for example be a part of the combustion chamber assembly group and can be provided in the area of a combustion chamber head of the combustion chamber. For example, this combustion chamber component can be a head plate of the combustion chamber. For affixing the constructional unit of burner seal and heat shield, the heat shield can for example form attachment elements that are passed through attachment openings at the combustion chamber component. Thus, for example bolts can be formed at the heat shield, which are inserted through attachment openings at a head plate of the combustion chamber head and which affix the constructional unit of burner seal and heat shield at the head plate by means of nuts that are screwed onto them.
In an embodiment variant explained above, in which the heat shield has an embracing section for the engaging around the at least one radially outwards extending web, a face side of the embracing section can be facing towards the combustion chamber component at which the constructional unit of burner seal and heat shield is affixed. Thus, the constructional unit adjoins the combustion chamber component via a face side of the embracing section and thus comes to rest—possibly after a thermal expansion that is possible during operation of the engine—at the combustion chamber component via the face side of the embracing section. Thus, an embracing section formed at the heat shield can replace a front positioning part, for example in the form of a positioning ring, which is usually provided in combustion chamber assembly groups as they are customary in practice on a side of a head plate that is facing towards the combustion space between the head plate (as a combustion chamber component) and the burner seal, and is in particular provided at a radial projecting web that is formed thereat.
Thus, in one embodiment variant only the heat shield is used for positioning the burner seal at the combustion chamber component and for abutment of the constructional unit at the combustion chamber component. Accordingly, no separate (front or rear) positioning part is provided here, which would be arranged between a section of the heat shield and the combustion chamber component or a section of the heat shield and the burner seal. Such a combustion chamber assembly group thus has no positioning ring, for example.
Alternatively, the constructional unit can also be combined with at least one separate positioning part. In such an embodiment variant, the combustion chamber assembly group comprises for example at least one separate positioning part, and thus a positioning part that does not form a part of the constructional unit of heat shield and burner seal, and that is arranged between the radially outwards extending web of the burner seal and a section of the combustion chamber component at which the constructional unit is affixed. Thus, the positioning part may for example be a (front) positioning ring that is arranged at the combustion chamber component from the side of the combustion space before the constructional unit of heat shield and burner seal is mounted.
In general, the opening edge can be formed to be symmetrical with respect to the longitudinal axis, for example circular with a constant wall thickness. However, the opening edge is not limited to such a design and can for example also be formed to be asymmetrical with respect to the longitudinal axis. Such an asymmetrical design in particular includes locally different wall thicknesses and/or inflection points in the course.
In one exemplary embodiment, the heat shield and/or the burner seal have at least one cooling air hole and/or at least one cooling rib or cooling nub.
For reducing the attachment elements to be used for affixing the combustion chamber assembly group at a combustion chamber at which multiple fuel nozzles are to be attached, for example in an annular combustion chamber of a gas turbine engine, it can be provided in one embodiment variant that the combustion chamber assembly group comprises at least two burner seals, and the heat shield has at least two passage holes through which respectively a bearing section of one of the at least two burner seals extends. Thus, here two or more burner seals are combined with a single heat shield with two passage holes, for example.
Besides, the proposed solution includes providing an engine, in particular a gas turbine engine, with at least one combustion chamber assembly group according to the invention.
A further aspect of the proposed solution relates to a method for manufacturing a combustion chamber assembly group with a burner seal and a heat shield. Here, too, the burner seal has a bearing section that extends along a longitudinal axis and has a passage hole for positioning a fuel nozzle at a combustion chamber of an engine. Further, when mounted according to the intended use at the combustion chamber of the engine, the heat shield is present inside the combustion space of the combustion chamber and has (at least) one passage hole through which the bearing section of the burner seal extends. In a method according to the invention, it is now further provided that the burner seal and the heat shield are manufactured in an additive manner as a constructional unit in which the burner seal and the heat shield cannot be separated from each other in a non-destructive way.
Analogously to a combustion chamber assembly group according to the invention, what is thus proposed here is to provide a [construction chamber] assembly group in which the burner seal and the heat shield form an (integral) constructional unit, whereby additional degrees of freedom can be obtained in particular with respect to an opening edge of the burner seal located in the combustion space, and/or the mounting of the burner seal and of the heat shield at the combustion chamber can be simplified.
In one embodiment variant, it is provided that the burner seal and the heat shield are manufactured in an additive manner in such a way that the heat shield at the constructional unit is at least partially received between (a) an opening edge of the passage hole formed by the burner seal and pointing radially outwards with respect to the longitudinal axis and (b) at least one web formed by the burner seal and also extending radially outwards with respect to the longitudinal axis. Thus, after an additive manufacture, for example by means of laser sintering, the heat shield is located between two radially projecting sections of the burner seal over which the heat shield cannot be separated from the burner seal in a non-destructive manner.
In one embodiment variant, it can alternatively or additionally be provided that the burner seal and the heat shield are manufactured in an additive manner in such a way that, at the finished constructional unit, the heat shield and the burner seal are axially, and where necessary also radially, displaceable with respect to each other with regard to the longitudinal axis.
In principle, an embodiment variant of a combustion chamber assembly group according to the invention can also be manufactured by means of an embodiment variant of a manufacturing method according to the invention. Consequently, the advantages and features described previously and in the following for the embodiment variants of a combustion chamber assembly group according to the invention also apply to the embodiment variants of manufacturing methods according to the invention, and vice versa.
The attached Figures illustrate possible embodiment variants of the proposed solution by way of example.

Herein:

FIGS. 1A-1B show, respectively in sections and in sectional views along two section lines A-A and B-B (compare FIGS. 9, 10 and 14), a first embodiment variant of a combustion chamber assembly group according to the invention in the area of a combustion chamber head of a combustion chamber;

FIGS. 2A-2B show a second embodiment variant, in views that correspond to FIGS. 1A and 1B;

FIGS. 3A-3B show a third embodiment variant, in views that correspond to FIGS. 1A and 1B;

FIGS. 4A-4B show a fourth embodiment variant, in views that correspond to FIGS. 1A and 1B;

FIGS. 5A-5B show a fifth embodiment variant, in views that correspond to FIGS. 1A and 1B;

FIGS. 6A-6B show a sixth embodiment variant, in views that correspond to FIGS. 1A and 1B;

FIGS. 7A-7B show a seventh embodiment variant, in views that correspond to FIGS. 1A and 1B;

FIGS. 8A-8B schematically show an additive manufacturing method for manufacturing an integral constructional unit of a burner seal and a heat shield according to FIGS. 4A and 4B along the steps A-A and B-B;

FIG. 9 shows a back view of two heat shields of a combustion chamber assembly group with respectively one burner seal, also showing different section lines A-A and B-B for the sectional views of FIGS. 1A to 7B;

FIG. 10 shows a back view of a heat shield of a combustion chamber assembly group with two passage holes for respectively one burner seal, also showing different section lines A-A and B-B for the sectional views of FIGS. 1A to 7B;

FIG. 11 shows an engine in which a combustion chamber assembly group according to FIGS. 1A to 10 is used;

FIG. 12 shows, in sections and on an enlarged scale, the combustion chamber of the engine of FIG. 11;

FIG. 13 shows, in a cross-sectional view, the basic structure of a combustion chamber from the state of the art on a scale that is more strongly enlarged with respect to FIG. 12;

FIG. 14 shows a back view of two heat shields of a combustion chamber assembly group, also showing different section lines A-A and B-B;

FIGS. 15A-15B show sectional views of a combustion chamber assembly group of the state of the art along the section lines A-A and B-B of FIG. 14.

FIG. 11 schematically illustrates, in a sectional view, a (turbofan) engine T in which the individual engine components are arranged in succession along a rotational axis or central axis M and the engine T is embodied as a turbofan engine. By means of a fan F, air is suctioned in along an entry direction at an inlet or an intake E of the engine T. This fan F, which is arranged inside a fan housing FC, is driven via a rotor shaft S that is set into rotation by a turbine TT of the engine T. Here, the turbine TT connects to a compressor V, which for example has a low-pressure compressor 111 and a high-pressure compressor 112, and where necessary also a medium-pressure compressor. The fan F supplies air to the compressor V in a primary air flow F1, on the one hand, and, on the other, to a secondary flow channel or bypass channel B in a secondary air flow F2 for creating a thrust. Here, the bypass channel B extends about a core engine that comprises the compressor V and the turbine TT, and also comprises a primary flow channel for the air that is supplied to the core engine by the fan F.
The air that is conveyed via the compressor V into the primary flow channel is transported into the combustion chamber section BKA of the core engine where the driving power for driving the turbine TT is generated. For this purpose, the turbine TT has a high-pressure turbine 113, a medium-pressure turbine 114, and a low-pressure turbine 115. The turbine TT drives the rotor shaft S and thus the fan F by means of the energy that is released during combustion in order to generate the necessary thrust by means of the air that is conveyed into the bypass channel B. The air from the bypass channel B as well as the exhaust gases from the primary flow channel of the core engine are discharged via an outlet A at the end of the engine T. Here, the outlet A usually has a thrust nozzle with a centrally arranged outlet cone C.
FIG. 12 shows a longitudinal section through the combustion chamber section BKA of the engine T. Here, in particular an (annular) combustion chamber BK of the engine T can be seen. A nozzle assembly group is provided for injecting fuel or an air-fuel-mixture into a combustion space 23 of the combustion chamber BK. It comprises a combustion chamber ring along which multiple nozzles 17 are arranged along a circular line about the central axis M. Here, the nozzle exit openings of the respective nozzles 17 that are positioned inside the combustion chamber BK are provided at the combustion chamber ring. Here, each nozzle 17 comprises a flange by means of which a nozzle 17 is screwed to an outer housing 22 of the combustion chamber section BKA.
FIG. 13 shows, on a scale that is once more enlarged with respect to FIG. 12 and in sectional rendering, a combustion chamber BK as it is known from the state of the art, and in particular the design of a burner seal 4 and a heat shield 2 in the area of a combustion chamber head 3 of the combustion chamber BK, as it is provided in this context. Here, the shown combustion chamber BK may for example be a (full) annular combustion chamber, as it is used in gas turbine engines.
The combustion chamber BK is arranged in the interior of the outer housing 22. The combustion chamber BK comprises (radially) outer and (radially) inner combustion chamber walls 1 a and 1 b. Depending on the construction, these combustion chamber walls 1 a, 1 b are shielded off against the combustion space 23 with a second wall 6, where necessary. This second wall 6 can be connected to the inner and outer combustion chamber walls 1 a, 1 b by means of bolts 10 and nuts 11, for example. The combustion chamber walls 1 a and 1 b usually have cooling holes 12 and mixing air holes 7. Likewise, the inner wall 6 can be provided with effusion cooling holes 13. The outer combustion chamber wall 1 a is connected to the outer housing 22 via an arm 8 and a flange 9.
In a—with respect to a longitudinal axis L—frontal end of the combustion chamber BK, a combustion chamber head 3 with a combustion chamber component in the form of a head plate 5 is provided. The outer and inner combustion chamber walls 1 a and 1 b are connected to each other by means of this combustion chamber head 3 and the head plate 5. The head plate 5 shown herein has cooling holes 15. Further, a passage hole which provides access to the combustion space 23 and [inside of which] the fuel nozzle 27 is provided is formed at the head plate 25.
Here, the burner seal 4 ensures a positioning of the fuel nozzle 27 in the head plate 5 and in particular inside the passage hole of the head plate 5. Here, the burner seal 4, which may also be provided with cooling holes 16 where necessary, is floatingly mounted, and in the shown embodiment variant from the state of the art is positioned at the head plate 5 by means of a front positioning part in the form of a front positioning ring 24 and by means of a rear positioning part in the form of a rear positioning ring 28. Further, the burner seal 4 is screwed together with a heat shield 2 that is positioned inside a combustion space 23. For this purpose, the heat shield 2 forms bolts 17 which are passed through attachment openings at the head plate 5 and onto which nuts 11 are screwed in from the side of the combustion chamber head 3. Here, the access for mounting the nuts 11 is facilitated through holes 19 provided in the combustion chamber head 3. According to the rendering of FIG. 13, the heat shield 2 can in principle also have cooling air holes 14 and cooling ribs or cooling nubs 29. Besides, the bolts 17 can be embodied as separate structural components and thus not be formed by the heat shield 2. Such bolts 17 are then screwed into threaded openings of the heat shield 2 from the side of the combustion chamber head 3, for example.
In the back view of FIG. 14, two heat shields 2 succeeding each other along the circumference of the combustion chamber 23 are shown in sections, as well as the arrangement of the bolts 17 in relation to a passage hole 26 of the respective heat shield 2 through which the burner seal 4 extends with a bearing section 41 for positioning the fuel nozzle 17.
As illustrated based on the sectional renderings of FIGS. 15A and 15B along the section lines A-A and B-B that are shown in FIG. 14, here the burner seal 4 projects with the bearing section 41 through the passage hole 26 of the respective heat shield 2 when the combustion chamber assembly group is mounted according to the intended use. In that case, the bearing section 41 projects into the combustion space 23 with an opening edge 40 that forms the combustion-space-side end of a passage hole 400 for positioning of the fuel nozzle 17. This opening edge 40 widens up to a diameter D along the longitudinal axis L along which the bearing section 41 extends, and thus points radially outwards.
For positioning and mounting the burner seal 4 at the head plate 5 according to the intended use, the bearing section 41 forms a web 42 at its outer surface area, with the web 42 extending circumferentially in a ring-like manner and radially outwards. Thus, the radially outwardly extending web forms a (ring-shaped) projection or a radial web 42 at the burner seal 4. Here, the radial web 42 is received between the two positioning rings 24 and 28 in a form-fit manner, and in this way is floatingly mounted at the head plate 5. During operation of the engine T, the burner seal 4 is thus supported so as to be displaceable in the axial direction (with respect to the longitudinal axis L) relative to the head plate 5, and can also extend in the radial direction.
To ensure a positioning of the burner seal 4 at the head plate 5 according to the intended use, the heat shield 2 that is screwed together with the head plate 5 is supported, on the one side, on an inner side of the head plate 5 that faces towards the combustion space 23.
For this purpose, a radially outwardly positioned outer edge 2 b of the heat shield 2 is located at the inner side of the head plate 5, when the combustion chamber assembly group is mounted according to the intended use. Further, the heat shield 2 forms a radially inwardly located inner edge 2 a at which the rear positioning ring 28 can abut. The projecting radial web 42 of the burner seal 4 is thus partially received between the two front and rear positioning rings 24 and 28, while the rear positioning ring 28 is positioned at least partially between the projecting radial web 42 and the inner edge 2 a of the heat shield 2.
Consequently, when mounting the combustion chamber assembly group as illustrated based on the mounting order including the steps 1 to 5 in FIGS. 15A and 15B, initially 1. the front positioning ring 24 has to be inserted and arranged at the head plate 5 from the side of the combustion space 23. Then, 2. the burner seal 4 follows from the side of the combustion space 23, before 3. the rear positioning ring 28 is inserted. Ultimately, 4. the heat shield 2 is arranged, which is 5. fixedly screwed together with the head plate 5 by means of the bolts 17 and nuts 11 from the side of the combustion chamber head 3 to affix the combustion chamber assembly group at the head plate 5. The individual components, front positioning ring 24, burner seal 4, rear positioning ring 28 and heat shield 2 are thus arranged at the head plate 5 and in particular inside its passage hole in succession along a first attachment direction R1 beginning in the combustion space 23. Subsequently, the placement of the nuts 11 and thus the affixing of the heat shield 2 of the head plate 5 was performed along an opposite attachment direction R2, whereby the burner seal 4 is positioned and floatingly mounted according to the intended use.
In a combustion chamber assembly group of FIGS. 15A and 15B as it is known from the state of the art, it is obligatory corresponding to a previously illustrated mounting order to embody the diameter D of the opening edge 40 at the end of the bearing section 41 so as to be at least a little smaller than the passage hole 26 of the heat shield 2. Otherwise, the heat shield 2 cannot be pushed with its passage hole 26 over the opening edge 40 and the heat shield 2 cannot be screwed to the head plate 5. However, a larger diameter of the opening edge 40 is in principle desirable here with a view to guiding the fuel-air mixture from the fuel nozzle 27 that is inserted into the passage hole 400 of the bearing section 41 in order to reduce soot emissions during operation of the engine T. Thus, the guidance of the fuel-air mixture and the intermixing in the primary zone would be improved by means of an opening edge 40 that widens more strongly, i.e. up to a larger diameter. Further, it would be desirable to render the previously described mounting easier.
The solution according to the invention remedies this problem.
In this context, it is provided in the embodiment variants shown in the attached FIGS. 1A to 7B, 8A to 8B, 9 and 10 that the burner seal 4 and the heat shield 2 are manufactured together in an additive manner as an integral constructional unit in one manufacturing process. In this way, in the shown embodiment variants, the burner seal 4 and heat shield 2 are inseparably connected to each other in such a way that the heat shield 2 is received at least partially between the radially outward pointing opening edge 40 and the radially outwardly extending radial web 42.
By integrating the burner seal 4 and the heat shield 2 in one constructional unit, the limitation which dictates that the diameter D of the passage hole 26 in the heat shield 2 may not be exceeded by the diameter of the opening edge 40 no longer applies. Thus, the embodiment variant of FIGS. 1A and 1B for example illustrates a first embodiment variant of a combustion chamber assembly group, in which the opening edge 40 is widened considerably stronger as compared to the variant as it has so far been known from the state of the art of FIGS. 15 A and 15B, and namely up to a diameter D_O. The diameter D_Ois considerably larger than the diameter D of the passage hole 26 in the heat shield 2 and exceeds it e.g. by at least 5%. Further, here the opening edge 40 extends at an opening angle α in the range of 20° and 50°, e.g. in the range of 35° to 50° and in particular of approximately 40°, with respect to the longitudinal axis L. Also in this way, the guidance of the fuel-air mixture and the intermixing in the primary zone can be improved.
Now, during mounting of the combustion chamber assembly group, a possibly still present front positioning ring 24 is inserted from the side of the combustion space, before then the constructional unit of burner seal 4 and heat shield 2 is placed at the head plate 5 and subsequently affixed (mounting sections 1., 2. and 3. in FIGS. 1A and 1B). In the embodiment variant of FIGS. 1A and 1B, a rear position ring 28 is correspondingly integrated into the heat shield 2, so that, with a positioning section 20 a at its inner edge 2 a, the heat shield 2 is positioned directly opposite the edge web 42 of the burner seal 4. As further indicated in FIGS. 1A and 1B, the heat shield 2 can also integrate the front position ring 24 and consequently radially engage around the web 42. This will be explained in more detail in the following in particular by referring to the embodiment variant of FIGS. 3A and 3B.
In the embodiment variant of FIGS. 2A and 2B, the positioning ring 24 is also maintained. However, the heat shield 2 and the burner seal 4 are also formed as a constructional unit that is manufactured in an additive manner. The opening edge 40 of the burner seal 4 further has an opening angle α of between 20° and 50°. Further, the widening opening edge 40 extends into the combustion space 23 with a comparatively great axial length to guide the fuel-air mixture in a targeted manner from the fuel nozzle 17 into the interior of the combustion space 23. Here, the radial extension of the opening edge 40 also leads to a larger diameter than the passage hole 26 in the heat shield 2 and the passage hole in the head plate 5.
In the embodiment variant of FIGS. 3A and 3B, the heat shield 2 is embodied with an embracing section 2 c that engages around the radial web 42 of the burner seal 4. The embracing section 2 c defines an annular gap 200 which extends circumferentially in a circular manner and inside of which the radial web 42 is received in a form-fit manner. Here, the embracing section 2 c in particular still ensures axial displaceability of the burner seal 2 along the longitudinal axis L during operation of the engine T, so that the burner seal 2 is floatingly mounted here, as well.
In the embodiment variant of FIGS. 4A and 4B, which in this regard corresponds to the embodiment variant of FIGS. 3A and 3B, it is additionally provided that the contour of the [heat shield] 2 follows the contour of the opening edge 40. For this purpose, an abutment section 21 b of the outer edge 2 b for abutment at a radially outer area of the head plate 5 (at the inner side of the head plate 5 that is facing towards the combustion space 23) is also formed with a larger axial length.
In the embodiment variant of FIGS. 5A and 5B, the opening edge 40 of the burner seal 4 is displaced radially outwards so far that the opening edge 40 takes over the function of the heat shield 2 (at least partially). Here, the opening edge 40 extends at least up to the radially outermost outer edge 2 b of the heat shield 2, so that the opening edge 40, as viewed from the combustion space 23 along the longitudinal axis L, completely covers the heat shield 2. As the opening edge 40 takes over the function of the heat shield 2 (at least partially), it can be designed with cooling air holes 14 or a corresponding internal cooling according to DE 10 2016 212 649.0. The heat shield 2 can further be designed in a simpler manner, for example without any cooling air holes 14 and/or without cooling ribs or cooling nubs 29.
FIGS. 6A and 6B as well as 7A and 7B illustrate further developments of the embodiment variants of FIGS. 5A and 5B or of FIGS. 3A and 3B. Here, the shown further developments illustrate that, in contrast to the embodiment variants of FIGS. 5A and 5B as well as 3A and 3B, it is not obligatory that the opening edge 40 is formed symmetrically to the longitudinal axis L. Thus, the opening edge 40 can also be designed asymmetrically and can have locally different wall thicknesses and/or inflection points in its course.
Based on FIGS. 8A and 8B, an additive manufacturing method for the constructional unit of heat shield 2 and burner seal 4 is schematically illustrated. Here, the constructional unit is built up layer by layer on a base plate 30, for example as a part of a laser sinter machine. At that, component areas and structural component sections that are not in direct contact with other structural component sections or areas or the base plate 30 (in particular those sections and areas that are built up at an angle of less than 40° to the longitudinal axis L) are supported by means of one or multiple support constructions 31. At that, such a support construction 31 can also be built up in an additive manner layer by layer, for example. However, in that case it does not form a part of the combustion chamber assembly group at the finished constructional unit of heat shield 2 and burner seal 4, and may for example be removed again for this purpose.
As is illustrated based on the steps in FIGS. 9 and 10 for respectively two different back views of different combustion chamber assembly groups, the embodiment variants of FIGS. 1A to 7A can be part of a combustion chamber assembly group in which a heat shield 2 having exactly one passage hole 26 for screwing on at the head plate 5 is provided per fuel nozzle 17 and thus per burner seal 4 (FIG. 9). Alternatively, the combustion chamber assembly group can comprise a heat shield 2 at which two passage holes 26 for respectively one of at least two combustion chamber seals 4 is provided. In this way, the number of the attachment elements to be used—here in the form of bolts 17—that are necessary for affixing a head plate 5 can be considerably reduced.
In addition, it is to be understood that possible cooling holes or cooling air holes 14 in the burner seal 4 and/or the heat shield 2 as well as any cooling ribs or cooling nubs 29 at the heat shield 2 can be manufactured integrally by an additive manufacturing method. In this context, it is also to be understood that cooling holes and cooling channels can in particular be formed according to DE 10 2016 212 649.0 at the burner seal 4 and/or the heat shield 2.

PARTS LIST

1 a, 1 b (outer/inner) combustion chamber wall
10 bolt (attachment element)
11 nut
111 low-pressure compressor
112 high-pressure compressor
113 high-pressure turbine
114 medium-pressure turbine
115 low-pressure turbine
12 cooling hole
13 effusion cooling hole
14 cooling air hole
15 cooling hole
16 cooling hole
17 bolt
19 hole
2 heat shield
200 annular gap
22 outer housing
23 combustion space
24 frontal position ring
26 passage hole
27 fuel nozzle
28 rear position ring
29 cooling rib/cooling nub
2 a inner edge
20 a positioning section
2 b outer edge
21 b abutment section
2 c embracing section
3 combustion chamber head
30 base plate
31 support construction
4 burner seal
40 opening edge
400 passage hole
41 bearing section
42 (ring-shaped) projection/radial web
5 head plate (combustion chamber component)
6 wall
7 mixing air hole
8 arm
9 flange
A outlet
B bypass channel
BK combustion chamber
BKA combustion chamber section
C outlet cone
D, D_Odiameter
E inlet/intake
F fan
F1, F2 fluid flow
FC fan housing
L longitudinal axis
M central axis/rotational axis
R1, R2 installation direction
S rotor shaft
T (turbofan) engine
TT turbine
V compressor
α angle

Claims

1. Combustion chamber assembly group, comprising

a burner seal (4) with a bearing section (41) that extends along a longitudinal axis (L) and has a passage hole (400) for positioning a fuel nozzle (17) at a combustion chamber (BK) of an engine (T), wherein

(a) at an end of the passage hole (400), the bearing section (41) has an opening edge (40) which points radially outward with respect to the longitudinal axis (L) and which, when mounted according to the intended use at the combustion chamber (BK) of the engine (T), is located inside a combustion space (23) of the combustion chamber (BK), and

(b) at least one web (42) that extends radially outwards with respect to the longitudinal axis (L) is formed at the bearing section (41),

and

a heat shield (2) which, when mounted according to the intended use at the combustion chamber (BK) of the engine (T), is located inside the combustion space (23) of the combustion chamber (BK) and has a passage hole (26) through which the bearing section (41) of the burner seal (4) extends,

characterized in that

the burner seal (4) and the heat shield (2) form a constructional unit in which the heat shield (2) is at least partially received between the radially outward pointing opening edge (40) and the at least one radially outwardly extending web (42), so that any separation of the heat shield (2) from the burner seal (4) along the longitudinal axis (L) is excluded.

2. Combustion chamber assembly group according to claim 1, characterized in that the constructional unit of burner seal (4) and heat shield (2) are manufactured in an additive manner.

3. Combustion chamber assembly group according to claim 1 or 2, characterized in that the burner seal (4) is floatingly mounted at the heat shield (2).

4. Combustion chamber assembly group according to any of the claims 1 to 3, characterized in that, due to the radially outwardly pointing opening edge (40), the passage hole (400) of the burner seal (4) has a diameter (D_O) at its end that is located inside the combustion space (23) which is larger than a diameter (D) of the passage hole (26) in the heat shield (2).

5. Combustion chamber assembly group according to any of the preceding claims, characterized in that the opening edge (40) extends radially outwards up to the height of a radially outermost edge (2 b) of the heat shield (2) or beyond this radially outer edge (25 ba) of the heat shield (2), so that, when viewed from the combustion space (23) along the longitudinal axis (L), the opening edge (40) completely covers the heat shield (2).

6. Combustion chamber assembly group according to any of the preceding claims, characterized in that the opening edge (40) extends at an opening angle (a) in the range of approximately 20° to 50° with respect to the longitudinal axis (L).

7. Combustion chamber assembly group according to any of the preceding claims, characterized in that the heat shield (2) forms an embracing section (2 c) that engages around the at least one radially outwardly extending web (42) of the burner seal (4).

8. Combustion chamber assembly group according to claim 7, characterized in that the embracing section (2 c) defines a gap (200) inside of which the at least one radially outwardly extending web (42) is at least partially received.

9. Combustion chamber assembly group according to any of the preceding claims, characterized in that the constructional unit of burner seal (4) and heat shield (2) is affixed via the heat shield (2) at a combustion chamber component (5) that borders the combustion space (23).

10. Combustion chamber assembly group according to claim 9, characterized in that attachment elements (17) which are passed through attachment openings at the combustion chamber component (5) are formed for affixing the constructional unit of burner seal (4) and heat shield (2) at the heat shield (2).

11. Combustion chamber assembly group according to any of the claims 7 and 8 and according to any of the claims 9 and 10, characterized in that a face side of the embracing section (2 c) is facing towards the combustion chamber component (5).

12. Combustion chamber assembly group according to claim 9 or 10, characterized in that the combustion chamber assembly group comprises at least one separate positioning part (24) that is arranged between the radially outwardly extending web (42) of the burner seal (4) and a section of the combustion chamber component (5).

13. Combustion chamber assembly group according to any of the claims 9 to 11, characterized in that only the heat shield (2) is used for positioning the burner seal (4) at the combustion chamber component (5) and for abutment at the combustion chamber component (5).

14. Combustion chamber assembly group according to any of the preceding claims, characterized in that the opening edge (40) is formed to be symmetrical with respect to the longitudinal axis (L).

15. Combustion chamber assembly group according to any of the claims 1 to 13, characterized in that the opening edge (40) is formed to be asymmetrical with respect to the longitudinal axis (L).

16. Combustion chamber assembly group according to any of the preceding claims, characterized in that the heat shield (2) and/or the burner seal (4) have at least one cooling air hole (14) and/or at least one cooling rib or cooling nub (29).

17. Combustion chamber assembly group according to any of the preceding claims, characterized in that the combustion chamber assembly group comprises at least two burner seals (4) and the heat shield (2) has at least two passage holes (26) through which respectively one bearing section (41) of one of the at least two burner seals (4) extends.

18. Engine with at least one combustion chamber assembly group according to any of the claims 1 to 17.

19. Method for manufacturing a combustion chamber assembly group comprising a burner seal (4) with a bearing section (41) that extends along a longitudinal axis (L) and that has a passage hole (400) for positioning a fuel nozzle (17) at a combustion chamber (BK) of an engine (T), and a heat shield (2) which, when mounted according to the intended use at the combustion chamber (BK) of the engine (T), is located inside the combustion space (23) of the combustion chamber (BK) and has a passage hole (26) through which the bearing section (41) of the burner seal (4) extends,

characterized in that

the burner seal (4) and the heat shield (2) are manufactured in an additive manner as a constructional unit in which the burner seal (4) and the heat shield (2) cannot be separated from each other in a non-destructive manner.

20. Method according to claim 19, characterized in that the burner seal (4) and the heat shield (2) are manufactured in an additive manner in such a way that the heat shield (2) is at least partially received at the constructional unit between (a) an opening edge (40) of the passage hole (400) that is formed by the burner seal (4) and that points radially outward with respect to the longitudinal axis (L) and (b) at least one web (42) that is formed by the burner seal (4) and also extends radially outwards with respect to the longitudinal axis (L).

21. Method according to claim 19 or 20, characterized in that the burner seal (4) and the heat shield (2) are manufactured in an additive manner in such a way that, at the finished constructional unit, the heat shield (2) and the burner seal (2) are axially displaceable with respect to each other with regard to the longitudinal axis (L).