Nozzle assembly having swirl-free air and hydrogen inflow

Abstract

The proposed solution relates to a nozzle assembly for a combustor (103) of an engine (T), having at least one nozzle (D) for injecting hydrogen into a combustion chamber (1030) of the combustor (103), wherein the nozzle (D) has a nozzle main body (DH) which extends along a nozzle longitudinal axis (L) and a nozzle head (2) at one end of the nozzle main body (DH) and comprises a first air conduit (12; 21), a fuel duct (22) for the hydrogen to be injected, and a second air conduit (23). The fuel duct (22) is arranged with a fuel exit opening for the hydrogen to be injected into the combustion chamber (1030) between the first and second air conduits (12, 23; 21, 23) with their first and second air exit openings, in relation to a radial direction running perpendicularly to the nozzle longitudinal axis (L). Also according to the invention, at least the second air conduit (23), which is situated radially further outwards, is designed and provided to provide an non-swirled air flow into the combustion chamber (1030) and the fuel duct (22) is designed and provided to provide a non-swirled flow of hydrogen into the combustion chamber (1030).

Description

[0001] Nozzle assembly with swirl-free air and hydrogen inflow

[0002] Description

[0003] The proposed solution relates to a nozzle assembly for a combustion chamber of an engine with at least one nozzle for injecting hydrogen into a combustion chamber of the combustion chamber.

[0004] Nozzle assemblies for engine-mounted combustion chambers are widely known in various forms. The focus of conventional nozzles of such nozzle assemblies is the injection of liquid fuels, such as kerosene or diesel. Mixing the fuel with air usually occurs within the nozzle itself, creating an ignitable fuel-air mixture immediately downstream of the nozzle end. Typically, the air to be mixed is already wired within the nozzle, creating a swirling fuel-air flow with comparatively high turbulence downstream of the nozzle end, which is considered advantageous for kerosene combustion, for example.

[0005] Recently, engine concepts have increasingly been developed in which the engine is partially or entirely powered by hydrogen. However, if an engine is to be powered by hydrogen instead of kerosene or diesel while maintaining as similar a design as possible, a different injection of the hydrogen used is necessary. The hydrogen is introduced into the combustion chamber in gaseous form and is also significantly more flammable. Against this background, the nozzle assembly of claim 1 is proposed, which comprises a nozzle for injecting hydrogen into a combustion chamber of an engine-side combustion chamber.

[0006] A proposed nozzle has a nozzle main body extending along a longitudinal axis of the nozzle and a nozzle head at one end of the nozzle main body. The nozzle has at least one first air guide channel (e.g. in the nozzle main body or the nozzle head) to guide a first air flow towards the combustion chamber and into the combustion chamber via at least one first air outlet opening of the first air guide channel. At least one fuel channel and at least one second air guide channel are provided on the nozzle head of the nozzle. The fuel channel is designed to guide hydrogen towards the combustion chamber. A second air flow can be guided towards the combustion chamber via the at least one second air guide channel and into the combustion chamber via at least one second air outlet opening of the second air guide channel.In a proposed nozzle with a fuel outlet opening for the hydrogen to be injected into the combustion chamber, the fuel channel is arranged between the first and second air guide channels with their first and second air outlet openings, relative to a radial direction perpendicular to the nozzle's longitudinal axis. Furthermore, it is provided that at least the second air guide channel, located radially further outward, is configured and provided to provide an unswirled air flow into the combustion chamber, and the fuel channel is configured and provided to provide an unswirled flow of hydrogen into the combustion chamber.

[0007] The proposed solution is therefore based on the basic idea of ​​introducing at least one radially outer air flow and one hydrogen flow into the combustion chamber with as little swirl as possible in order to prevent coherent structures in the flow, so that both the air flow from the radially outer second air guide channel and the hydrogen flow from the fuel channel are introduced into the combustion chamber with the greatest possible flow velocity in the axial direction (relative to the longitudinal axis of the nozzle). In addition, a nozzle of a proposed nozzle assembly is designed to introduce hydrogen and air into the combustion chamber unmixed, i.e. without mixing within the nozzle. In combination with the high axial flow velocities of the hydrogen and air achievable using the proposed nozzle assembly, this means that an ignitable fuel-air mixture only develops downstream of one end of the nozzle.Considering the highly flammable nature of hydrogen, this is an advantage as it allows combustion to take place further downstream of the nozzle end.

[0008] In particular, the nozzle of the proposed nozzle assembly can be configured and provided for rich quench lean combustion.

[0009] In one embodiment, at least the second radially outermost air duct and the fuel duct extend radially outward at their respective duct ends (having the second air outlet or the fuel outlet). Both the second radially outermost air duct and the fuel duct thus have a radially outwardly extending duct section at one nozzle end, so that the air or hydrogen discharged therefrom exhibits a radially outward flow component during engine operation.

[0010] In particular, in this context, it can be provided that the second air guide duct located radially further outward comprises a duct section having the second air outlet opening, which runs at an angle in the range of 30° to 60° to the nozzle longitudinal axis, in particular at an angle in the range of 35° to 50° to the nozzle longitudinal axis. Alternatively or additionally, the fuel duct can comprise a duct section having the fuel outlet opening, which runs at an angle in the range of 30° to 60°, in particular in the range of 35° to 50° to the nozzle longitudinal axis. If a respective duct section of the air guide duct and / or the fuel duct having the associated outlet opening runs radially outward at such a comparatively large (opening) angle to the nozzle longitudinal axis, the formation of a recirculation zone downstream of the nozzle end can be supported.Combustion temperatures in the immediate vicinity downstream of the nozzle end can thus be kept comparatively low, even though more easily flammable hydrogen is injected into the combustion chamber.

[0011] In order to increase the flow velocities at which hydrogen and air are introduced into the combustion chamber from the fuel channel and the second air guide channel located further radially outwards, and if necessary to keep a boundary layer (in which the velocity is lower) thin, one embodiment variant can provide for the fuel channel and / or the second air guide channel located further radially outwards to taper towards a respective channel end. This includes, for example, the fuel channel and / or the second air guide channel having two channel sections adjoining one another in the flow direction of the respective fluid (hydrogen or air), of which a second channel section having the respective outlet opening is designed to taper towards the channel end. Such a second channel section can also be designed with a radially outward-facing course.

[0012] In principle, the two channel sections adjoining each other in the direction of flow of the respective fluid can also be designed with different courses and / or flow cross-sections. For example, a first channel section can be designed with a straight line or one that tapers towards the second channel section along the nozzle's longitudinal axis. This first channel section is then followed by the second channel section, which may taper further.

[0013] In one embodiment, a central fuel supply line is provided in the nozzle main body for supplying hydrogen to the fuel channel. This specifically means that the central fuel supply line runs centrally along the nozzle's longitudinal axis in the nozzle main body.

[0014] In order to guide hydrogen from a central fuel supply line into the radially outer fuel channel, at least one corresponding fluid guide can be provided on the nozzle head. Part of such a fluid guide is then provided, for example, within a radially outwardly extending strut of the nozzle head, which runs through a section of the first air guide channel. Via the fluid guide accommodated in one or more radially extending struts, the hydrogen originating from the central fuel supply line is thus guided radially outwards and (in each case protected within the strut) through the first, radially inner air guide channel to the fuel channel, via which the hydrogen is injected into the combustion chamber.

[0015] In principle, one or more struts extending radially on the nozzle head can also serve to fix the sections of the nozzle head forming the first and second air guide channels and the fuel channel to the nozzle main body.

[0016] In one embodiment, a stabilizing body is provided centrally at one end of the nozzle, comprising a substantially flat end face facing the combustion chamber. Thus, a substantially flat end face is provided on the stabilizing body, at which air and hydrogen are introduced via the first and second air outlet openings and the fuel outlet openings, radially further outward at the edge. A central stabilizing body with a substantially flat and, in particular, comparatively large end face supports the formation of a zone in the immediate area downstream of the nozzle end, in which the axial velocity is comparatively low, thus creating a stable recirculation zone that ensures flame stability.Furthermore, a corresponding stabilizing body can not only serve to stabilize the flow and flame within the combustion chamber, but also facilitate the (pre-)evaporation of the hydrogen gas that is to be injected. Thus, hydrogen can be (pre-)evaporated on the stabilizing body itself.

[0017] For more compact integration of the stabilizing body at the nozzle end, the stabilizing body can define at least part of an inner wall of the first radially inner air duct with an outer surface. The first radially inner (and in one further development, the furthest radially inner) air duct thus guides air along the outer surface of the stabilizing body. The stabilizing body can also define, with its outer surface, a radially outward-facing inner wall section for the first air duct, so that the first air duct extends radially outward at its duct end.Analogous to a possible course of the second air guide channel and / or the fuel channel mentioned above, in a further development based thereon, the first air guide channel can also run at its channel end at an angle in the range of 30° to 60°, in particular of 35° to 50°, to the nozzle longitudinal axis.

[0018] Alternatively or additionally, the first radially inner air duct, which extends at least partially along a radially outer surface of the stabilizing body, can taper towards its end. In such a design variant, this also achieves a corresponding acceleration of the air flow from the first air duct. The acceleration of the flow from the first air duct can also reduce the influence of any webs present in the first air duct on the air flow, so that the air flow is largely uniform.

[0019] With a view to achieving the largest possible recirculation zone downstream of the nozzle end, the essentially flat end face of the nozzle-side stabilizing body facing the combustion chamber can be designed with a comparatively large area. For this purpose, it is provided, for example, that this end face has an extension in the radial direction, relative to the nozzle's longitudinal axis, that corresponds to at least twenty times, in particular at least thirty times or forty times, the channel height of the first air guide channel at the first air outlet opening and / or the channel height of the second air guide channel at the second air outlet opening and / or the channel height of the fuel channel at the fuel outlet opening.For example, the ratio of a diameter of a circular end face of the stabilizing body to a channel height of a respective referenced channel for the incoming air or the hydrogen to be injected can be at least 20:1, 30:1, or 40:1. This emphasizes the comparatively large extent of the end face of the stabilizing body in relation to a flow-through cross-sectional area available at the respective outlet opening of a first or second air outlet channel and / or a fuel channel.

[0020] In principle, a first or second air outlet channel and / or a fuel channel can be configured as an annular gap or annular segment gap at the nozzle end. Thus, the respective annular gap or annular segment gap extends circumferentially (completely in the case of an annular gap, or partially in the case of an annular segment gap) around the end face of the stabilizing body.

[0021] In one design variant, cooling is provided for the stabilizing body. Such cooling can be achieved, for example, using air or hydrogen. With hydrogen cooling, the injected hydrogen can be used for this purpose, so that the stabilizing body serves to (pre-)evaporate the injected hydrogen before the hydrogen is subsequently injected into the combustion chamber. This also makes it easier, for example, to ensure that the hydrogen can initially be supplied to the nozzle head in liquid form.

[0022] In principle, at least a portion of the fluid guide, through which hydrogen is guided from a central fuel supply line in the nozzle main body into the radially outer fuel channel, can be provided at least partially within the stabilizing body. This includes, in particular, that a portion of the fluid guide provided within the stabilizing body is also provided for cooling the stabilizing body.

[0023] In one possible further development, this is achieved, for example, in that, for impingement cooling of the stabilization body with hydrogen, hydrogen is guided against a rear wall of the stabilization body facing away from the combustion chamber via the part of the fluid guide provided inside the stabilization body. The rear wall, which forms a rear side of the end face facing the combustion chamber, can thus be cooled by the hydrogen flowing onto the rear wall before the hydrogen is then guided radially outwards to the fuel channel. At least part of the fluid guide for the hydrogen is thus designed within the stabilization body in such a way that, during operation of the engine, impingement cooling for the stabilization body takes place via the hydrogen to be injected, before the hydrogen is guided radially outwards in the nozzle head to the fuel channel and via this into the combustion chamber without swirl.

[0024] In an alternative embodiment, which does not require a central fuel supply line and possibly a centrally arranged stabilizing body, a first air guide channel can be provided centrally on the nozzle main body, running along the nozzle's longitudinal axis. A fuel supply line for the fuel channel is then provided in the nozzle main body in a radially outer section of the nozzle main body.

[0025] In such a variant, the first central air guide channel can be designed to widen, for example, at its channel end having the first air outlet opening. With the radial widening, for example, a radially outwardly extending flow guide element is formed on the first air guide channel. This flow guide element can, for example, run radially outwards at an angle in the range of 30° to 60° to the nozzle longitudinal axis, in particular at an angle in the range of 35° to 50° to the nozzle longitudinal axis. In particular, in interaction with a non-swirling air flow from the second air guide channel located radially further outwards and a non-swirling flow of hydrogen from the fuel channel, possibly also directed radially outwards, such a configuration of a nozzle for the injection of hydrogen can also prove advantageous.In contrast to the second air duct and the fuel duct, condensation of the air in the first air duct can also be advantageous. For this purpose, at least one swirl element is provided in the first air duct, for example.

[0026] In a variant with a central first air duct, a possible further development provides a centrally arranged flow divider. This flow distributor divides the air flow within the first air duct toward a nozzle end into an inner and an outer air duct section. The flow divider thus enables two separate partial air flows radially inward relative to the fuel outlet opening of the fuel duct. An outer air duct section can deliver a more accelerated partial air flow toward the fuel being introduced. The central inner air duct section provides a comparatively slower partial air flow, which primarily serves to lean out the resulting fuel-air mixture.As a result, the resulting fuel-air mixture is not immediately flammable in the near field of the nozzle and thus prevents higher temperatures in the immediate vicinity of the nozzle end.

[0027] The flow divider can, for example, be designed with a central tube section with a constant cross-sectional area along the longitudinal axis of the nozzle and a diffuser part adjoining the tube section (downstream) towards the nozzle end, wherein the diffuser part has a cross-sectional area that increases along the longitudinal axis of the nozzle and thus widens radially outwards. In combination with a radially outwardly extending flow guide element of the first air duct, the outer air duct part can be bordered (radially outward) by the flow guide element and (radially inward) by the diffuser part. The outer air duct part can then also point radially outwards. In particular, the outer air duct part can also be designed as an annular gap in the region of the nozzle end.

[0028] The air outlet opening portion defined by the inner air duct portion can have a cross-sectional area (through which air flows) at the nozzle end that is at least 8 times larger, in particular at least 10 times larger, than the cross-sectional area (through which air flows) of that portion of the first air outlet opening defined by the outer air duct portion. The central, inner air duct portion thus defines a portion of the air outlet opening that is significantly larger in cross-section than the outer air duct portion, which is separated from the inner air duct portion by the diffuser portion and is formed in a ring-shaped manner radially outward.

[0029] In one embodiment, an axially flowable flow body can be provided in the inner air duct section to even out the partial air flow. For this purpose, the flow body is provided in the pipe section of the flow divider. For example, a design with a flow divider in the central / middle first air duct precisely ensures that an unswirled air flow is generated into the combustion chamber via the central first air duct. Consequently, in such a design, a first central air duct is also designed without swirl elements. Accordingly, no swirlers are provided on any centrally arranged flow body in a pipe section of a flow divider.

[0030] In principle, the first and second air outlet openings and the fuel outlet opening can be located in a radial plane running perpendicular to the nozzle's longitudinal axis. Thus, in such a design variant, the individual outlet openings are not axially offset from one another. However, a design variant is also conceivable in which the outlet openings are axially offset from one another. In such a case, for example, the further radially outward the respective outlet opening is located, the further downstream it is axially. An innermost outlet opening, for example a central one, or part thereof, is thus axially set back from a radially outermost outlet opening and thus located further upstream.

[0031] The proposed solution further comprises an engine with at least one embodiment of a proposed nozzle assembly.

[0032] The attached figures illustrate possible embodiments of the proposed solution.

[0033] Here we show:

[0034] Figure 1A shows a detail of the end of a nozzle of a first

[0035] Design variant of a proposed nozzle assembly;

[0036] Figure 1B is a sectional view of the nozzle of Figure 1A;

[0037] Figure 1C shows a further sectional view of a further development of the nozzle of the

[0038] Figures 1A and 1B illustrate an impingement cooling system for a central stabilization body and a fluid guide for hydrogen to a radially outer fuel channel;

[0039] Figure 2A shows a perspective view and a detail of a nozzle of a further embodiment of a proposed nozzle assembly;

[0040] Figure 2B is a sectional view of the nozzle of Figure 2A; Figure 3A is a view of a nozzle of another embodiment of a proposed nozzle assembly, looking toward a nozzle end;

[0041] Figure 3B is a sectional view of the nozzle of Figure 3A in a built-in

[0042] Condition;

[0043] Figure 4A in perspective view and in detail another

[0044] Design variant of a proposed nozzle assembly in which - analogous to the design variant of Figures 3A and 3B - a central first air guide channel is provided, via which, however, in contrast to the design variant of Figures 3A and 3B, an unswirled air flow is generated into a combustion chamber and a flow divider is integrated towards one end of the nozzle;

[0045] Figure 4B is a sectional view of the embodiment variant of Figure 4A;

[0046] Figures 5A-5B, in views corresponding to Figures 4A and 4B, show a further development of the embodiment variant of Figures 4A and 4B with outlet openings axially offset from one another;

[0047] Figure 6A shows an engine incorporating a variant of a proposed nozzle assembly;

[0048] Figure 6B shows a detail and an enlarged scale of the combustion chamber of the

[0049] Engine of Figure 6A.

[0050] Figure 6A illustrates schematically and in section a (turbofan) engine T, in which the individual engine components are arranged one behind the other along a rotational axis or central axis M and the engine T is designed as a turbofan engine. At an inlet or intake E of the engine T, air is sucked in along an inlet direction by means of a fan F. This fan F, arranged in a fan casing FC, is driven via a rotor shaft S, which is set in rotation by a turbine TT of the engine T. The turbine TT is connected to a compressor V, which has, for example, a low-pressure compressor 111 and a high-pressure compressor 112, and optionally also a medium-pressure compressor. The fan F, on the one hand, supplies the primary air flow F1 to the

[0051] Compressor V supplies air and, on the other hand, to generate thrust, in a secondary air flow F2 to a secondary flow duct or bypass duct B. The bypass duct B runs around a core engine comprising the compressor V and the turbine TT, which includes a primary flow duct for the air supplied to the core engine by the fan F.

[0052] The air fed into the primary flow duct via the compressor V enters a combustion chamber assembly BK of the core engine, in which the drive energy to drive the turbine TT is generated. The turbine TT has a high-pressure turbine 113, an (optional) medium-pressure turbine 114 and a low-pressure turbine 115. The turbine TT uses the energy released during combustion to drive the rotor shaft S and thus the fan F in order to generate the required thrust via the air fed into the bypass duct B. Both the air from the bypass duct B and the exhaust gases from the primary flow duct of the core engine flow out via an outlet A at the end of the engine T. The outlet A usually has a thrust nozzle with a centrally arranged outlet cone C.

[0053] Figure 6B shows a longitudinal section through the combustion chamber assembly BK of the engine T. This shows, in particular, an (annular) combustion chamber 103 of the engine T. A nozzle assembly is provided for injecting fuel or an air-fuel mixture into a combustion chamber 1030 of the combustion chamber 103. This nozzle assembly comprises a combustion chamber ring R, on which a plurality of nozzles D are arranged along a circular line around the central axis M at a combustion chamber head of the combustion chamber. One or more burner seals BD with bearing openings are provided on the combustion chamber ring R, on which nozzle heads of the respective nozzles D are held so that fuel can be injected into the combustion chamber 103 via them. Each nozzle D comprises a flange, via which a nozzle holder DH of the nozzle D is screwed to an outer housing G of the combustion chamber 103.

[0054] In order to be able to effectively inject hydrogen as fuel into the combustion chamber 1030 of the combustion chamber 103 via the nozzle D, the embodiment variants of Figures 1A to 3B of a proposed nozzle assembly each provide that the nozzle D has a fuel channel 22 for the hydrogen on a nozzle head 2, the fuel outlet opening of which is located in the radial direction, relative to a nozzle longitudinal axis L of the nozzle D, between two air outlet openings 12 and 23 or 21 and 23. Air from a first, radially inner air guide channel 12 or 21 and air from a second radially outer air guide channel 23 can flow into the combustion chamber 1030 via the air guide channels 12 / 21, 21 / 23.In order to inject the hydrogen and at least the air from the second radially outer air guide channel 23 with a comparatively high flow velocity and low turbulence, at least the second radially further outer air guide channel 23 is designed and provided to provide an unswirled air flow into the combustion chamber 1030 and the fuel channel 22 is designed and provided to provide an unswirled flow of hydrogen into the combustion chamber 1030.

[0055] While in the embodiments of Figures 1A to 1C and 2A to 2B a first radially inner air guide channel 21 is provided, which is formed on the nozzle head 2 and runs along an outer circumferential surface of a centrally arranged stabilizing body 10 of the nozzle D in order to generate an air flow into the combustion chamber 1030 that is as free from swirl as possible via the first air guide channel 21, the embodiment of Figures 3A to 3B provides a nozzle D in which the first air guide channel 12 is formed running centrally along the nozzle longitudinal axis 11 and provides a wired air flow with the aid of a swirl element 120.

[0056] As illustrated in the combination of Figures 1A, 1B and 1C, an embodiment variant of a proposed nozzle assembly shown here provides a nozzle D in which hydrogen can be guided via a central fuel supply line 11 extending along the nozzle longitudinal axis L in a nozzle main body 1 in the direction of a nozzle head 2 at the nozzle end. According to the sectional view in Figure 1C, this central fuel supply line 11 opens into a cavity 102 of a stabilization body 10. The cavity 102 is part of a fluid guide for the hydrogen to be injected, which is guided from the cavity 102 via fluid lines in radially extending struts 24 radially outwards to a fuel channel 22 with an annular cross-section.

[0057] The stabilization body 10 has a substantially planar end face 100, shown in Figure 1A in front view, which faces the combustion chamber 1030. This end face 100 is circular in the present case and occupies a large part of the cross-sectional area of ​​the nozzle head 2. Hydrogen and air are thus injected unmixed into the combustion chamber 1030 via the first and second air guide channels 21 and 23, each designed as an annular gap, and the fuel channel 22 located therebetween, also designed as an annular gap. This creates a stable flame downstream of the nozzle end and, in particular, not in the immediate vicinity behind the nozzle D. This is advantageous, particularly with regard to the comparatively highly flammable hydrogen, in order to keep combustion temperatures in the immediate vicinity behind the nozzle D lower.Furthermore, the stabilization body 10 can be used for (pre-)evaporation of the hydrogen to be injected via the hydrogen guided therein. The hydrogen guided to the stabilization body 10 for (pre-)evaporation can simultaneously serve to cool the stabilization body 10 and, in particular, its end face 10 facing the combustion chamber.

[0058] Thus, in the illustrated embodiment, the hydrogen flows through the central fuel supply line 11 against a rear wall 101 of the stabilizing body 10, which is remote from the combustion chamber 1030 and faces the cavity 102. The rear wall 101, and thus the stabilizing body 10, is thus impingement-cooled by the hydrogen flowing into the cavity 101. The hydrogen is then deflected between a tubular end piece 110 of the central fuel supply line 11 and the inner walls of the cavity 102 on the stabilizing body side and guided outward in a radial direction. Here, the hydrogen reaches the fuel channel 23 via one or more fluid lines in struts 24 distributed around the circumference. Each strut 24 can comprise one or more fluid lines.

[0059] In the illustrated embodiment, each strut 24 has a first strut part 24.1, which extends radially through the first air guide channel 21, which is partially bordered radially on the inside by an outer circumferential surface of the stabilizing body 10. A second strut part 24.2 of the strut 24, which is located radially further outward and in which no flood line for the hydrogen is provided, extends radially through the second air guide channel 23. The circumferentially distributed struts 24 thus hold the nozzle-head-side air guide channels 21, 23 and the fuel channel 22 to the stabilizing body 10 and thus to the nozzle main body 1.

[0060] As can be seen in particular from the sectional view of Figure 1B, both the first and second air guide channels 21 and 23 and the fuel channel 22 each have a channel section with the respective air outlet opening or fuel outlet opening towards the nozzle end, which runs at an angle α to the nozzle longitudinal axis L, which lies in the range of 35° to 50°. The air flows from the air guide channels 21 and 23 and the flow of hydrogen from the fuel channel 22 are thus directed comparatively strongly radially outwards, which supports the formation of a recirculation zone as far downstream as possible from the nozzle end. Furthermore, the first and second air guide channels 21 and 23 are designed here as an example with two channel sections 21A, 21B or 23A, 23B, which follow one another in the direction of air flow along the nozzle longitudinal axis L.A first channel section 21A and 23A runs essentially parallel and straight to the nozzle longitudinal axis L. The adjoining (second) channel section 21B and 23B then not only runs radially outwards at the angle a, but also tapers towards the respective air outlet opening.

[0061] According to the sectional view of Figure 1B, for example, the second duct section 21B of the first air duct 21 tapers from a gap width or duct height a11 to a gap width or duct height a12 at the associated first air outlet opening. The second duct section 23B of the second air duct 23 tapers in turn to almost the same extent from a duct height a21 to a duct height a22 at its second air outlet opening. The ratios a11:a12 and a21:a22 of the duct heights (and thus correspondingly the ratios of the cross-sectional area through which air flows at the inlet and outlet) are in the present case in the range from 1.5:1 to 3:1, in particular in the range from 1.7:1 to 2.3:1. The duct height a12 or a22 at the respective air outlet opening is thus at least by a factor of 1.5 or even by a factor of 3 lower than the duct height a11 or a21 at the inlet of the air into the second duct section 21B or 23B.Consequently, the cross-sectional area through which the fluid flows from the inlet to the outlet of the respective second channel section 21B or 23B is reduced by a factor in the range of 1.5 to 3.

[0062] As a result, the respective air flow is accelerated until it flows into the combustion chamber 1030, without a swirl element, and thus without swirling the air, being provided within the respective air guide duct 21, 23. The air is thus introduced into the combustion chamber 1030 via the two air guide ducts 21 and 23, each tapered towards the respective duct end, without swirling and at a comparatively high axial flow velocity. The same applies to the hydrogen injected via the intermediate fuel duct 22.

[0063] The illustrations in Figures 1B and 1C further illustrate the comparatively large end face 100 of the stabilizing body 10. Thus, a diameter d of the presently circular end face 100 corresponds to at least 20 times or even at least 30 or 40 times a channel height a12 or a22 of the first or second air guide channel 21 or 23. The channel heights a12 and a22 of the air guide channels 21 and 23 at the air outlet openings are in the same order of magnitude as a channel height of the fuel channel 22 at its fuel outlet opening (in principle, the channel heights a12 and a22 can be substantially identical to one another or differ from one another by a ratio of up to 1:3).

[0064] The sectional view of Figure 1C shows another possible refinement, in which a taper can also be provided in a first channel section 21A or 23A of the first or second air guide channel 21, 23, specifically in this case toward the respective second channel section 21B or 23B. The air flow is then already accelerated.

[0065] The embodiment of Figures 2A and 2B corresponds in some design details to the embodiments of Figures 1A to 1C, particularly with regard to the design of the stabilizing body 10 with its essentially flat end face 100 and its impingement cooling via centrally supplied hydrogen, which is then guided radially outward to the fuel channel 22. In the embodiment of Figures 2A and 2B, however, the air guide channels 21 and 23 as well as the fuel channel 22 are designed to extend radially outward at a smaller angle. In addition, only a single channel section, tapering towards the nozzle end, is provided for the first and second air guide channels 21 and 23.

[0066] In the embodiment shown in Figures 3A and 3B, in contrast to the embodiments shown in Figures 1A-1C and 2A-2B, no central fuel supply line 11 is provided for supplying the hydrogen to the nozzle head 2. Instead, a first air guide channel 12 is formed centrally. The hydrogen is supplied to the fuel channel 22, which continues to be annular in cross-section, in a radially outwardly located section of the nozzle main body 1.

[0067] In contrast to the embodiments of Figures 1A-1C and 2A-2B, the first air duct 12 of the embodiment of Figures 3A-3B does not conduct an air flow unswirled to the combustion chamber 1030. Rather, the first air duct 12 has a swirl element 120 (English: "swirler") upstream of the nozzle end to swirl incoming air.

[0068] At the end of the central first air guide channel 12 of Figures 3A-3B, the air flows out into the combustion chamber 1030 with a swirling effect. The first air guide channel 12 also expands radially outward at its channel end. A flow guide element 121 of the central air guide channel 12, which appears funnel-shaped when viewed from the combustion chamber 1030, extends at an (opening) angle to the nozzle longitudinal axis L that lies in the range of the angle α at which the fuel channel 22 and the radially outermost second air guide channel 23 extend radially outward toward their respective channel ends.The combination of swirled air flow from a central first air duct 12 in combination with hydrogen injected radially outwards without swirling and a second air flow flowing radially outwards without swirling from the second air duct 23 has also proven advantageous for operation of the engine T with hydrogen, even though the air flow from the central air duct 12 is injected into the combustion chamber 1030 at a lower axial flow velocity than the air from a first air duct 21 in Figures 1A-1C and 2A-2B. In the design of Figures 3A-3B, a recirculation zone is also formed in a central region downstream of the nozzle D and in particular of the nozzle head 2. The swirl additionally ensures that the flow opens outwards.

[0069] In the embodiments of Figures 4A-4B and 5A-5B, analogous to the embodiment of Figures 3A and 3B, a central first air guide channel 12 is also provided at the nozzle D for air flow into the combustion chamber 1030. However, in the embodiments of Figures 4A-4B and 5A-5B, the air from the central first air guide channel 12 is also introduced into the combustion chamber 1030 without swirling.

[0070] In each of the embodiments shown in Figures 4A-4B and 5A-5B, a flow divider 122 is provided within the first air duct 12 toward the nozzle end of the nozzle D. This flow divider 122 divides an air flow within the first air duct into two partial air flows: an inner partial air flow and an outer partial air flow. For this purpose, the flow divider 122 has a pipe section 122a with a constant cross-sectional area and a diffuser section 122b adjoining it downstream. The diffuser section 122b widens radially toward the nozzle end, so that its cross-sectional area continuously increases along the nozzle's longitudinal axis L. An inner air duct section 12.2 is defined within the pipe section 122a and the diffuser section 122b.An outer air duct section 12.1 is defined between a radially outer surface of the flow divider 122 and an inner surface of a duct wall of the first air duct 12. Toward the nozzle end, the section of the outer air duct section 12.1 is then bordered (radially outward) by the flow guide element 121 and (radially inward) by the widening diffuser section 122b. Thus, the outer air duct section 12.1 points radially outward and defines an annular gap at the nozzle end for the partial air flow introduced therethrough. The duct height of this annular gap is essentially the same size as the fuel outlet opening of the fuel duct 22 and the (second) air outlet opening of the radially outermost air duct 23.

[0071] Furthermore, the sectional views in Figures 4B and 5B not only show a strut 220 extending radially outward within the respective fuel channel 22, but above all also the geometry of the respective flow divider 122. Furthermore, an elongated central flow body 123 is visible, which is located in a cone-shaped manner centrally within the pipe section 122a. This flow body 123 can be axially flowed around within the respective pipe section 122a, so that within the pipe section 122a there is only a cross-sectional area through which the flow is carried that is merely annular in cross-section. This contributes to the homogenization of the untwisted inner partial air flow from the inner air guide channel section 12.2, via which the resulting fuel-air mixture in the near field of the nozzle D is to be leaned out.Consequently, additional air is introduced centrally along the nozzle longitudinal axis L in order to avoid combustion immediately downstream of the nozzle end and thus undesirable heating of the nozzle D.

[0072] The design variants of Figures 4A-4B and 5A-5B differ primarily in the design of the nozzle end and in the design of the flow divider 122 within the central first air duct 12.

[0073] Thus, in the embodiment shown in Figures 4A and 4B, the outlet openings of the air guide channels 12 and 23 and of the fuel channel 22 are not axially offset from one another and thus lie in a radial plane perpendicular to the nozzle's longitudinal axis L, as is also the case in the embodiment shown in Figures 1A to 3B. Accordingly, the diffuser part 122b of the flow divider 22 also extends axially to this radial plane.

[0074] In the embodiment of Figures 5A and 5B, however, an axial offset is provided between the outlet openings. The further radially inward the respective outlet opening is located, the further it is set back from the radially outermost and thus most axially protruding outlet opening of the second air duct 23 and thus arranged further upstream. For example, the part of the air outlet opening of the first air duct 12 that is defined by the inner air duct part 12.2 is axially furthest upstream. The diffuser part 122b thus has a shorter axial length in the embodiment of Figures 5A and 5B compared to the embodiment of Figures 4A and 4B. The cross-sectional area through which air flows through the inner air duct part 12.2 is thus still larger by a factor of at least 8 than the cross-sectional area of ​​that part of the air outlet opening defined by the outer air duct part 12.1, but significantly smaller than in the embodiment variant of Figures 4A and 4B. The positioning of the outlet openings and in particular their possible axial offset can vary depending on an application scenario and thus an engine T and / or, for example, depending on a desired flow pattern of the fuel-air mixture into the combustion chamber 1030.

[0075] Nozzle D of the variants shown in Figures 1A-1C, 2A-2B, 3A-3B, 4A-4B, and 5A-5B is designed and intended for rich quench lean combustion. In principle, the nozzle D shown can also be used for lean combustion concepts.

[0076] It is understood that the proposed solution is not limited to the embodiments described above, and various modifications and improvements may be made without deviating from the concepts described herein. Any of the features may be used separately or in combination with any other features, provided they are not mutually exclusive, and the disclosure extends to and encompasses all combinations and subcombinations of one or more features described herein.

[0077] List of reference symbols

[0078] 1 nozzle main body

[0079] 10 stabilizing bodies

[0080] 100 frontal area

[0081] 101 Rear wall

[0082] 102 Cavity

[0083] 103 Combustion chamber

[0084] 1030 combustion chamber

[0085] 10A, 10B interior wall section

[0086] 11 Central fuel supply line

[0087] 110 end piece

[0088] 12 (Central / middle) first air duct

[0089] 12.1 , 12.2 Outer / inner air duct section

[0090] 120 swirl element

[0091] 121 Flow guide element

[0092] 122 flow dividers

[0093] 122a pipe section

[0094] 122b Diffuser part

[0095] 123 flow bodies

[0096] 2 nozzle head

[0097] 21 First air duct

[0098] 21A, 21B canal section

[0099] 22 Hydrogen Channel

[0100] 22A, 22B canal section

[0101] 220 strut

[0102] 23 Second air duct

[0103] 24 strut

[0104] 24.1 , 24.2 Strut part

[0105] 111 Low-pressure compressors

[0106] 112 high-pressure compressors

[0107] 113 High-pressure turbine

[0108] 114 medium-pressure turbine

[0109] 115 Low-pressure turbine

[0110] A Outlet a11 , a12, a21, a22 Channel height B Bypass channel

[0111] BK combustion chamber assembly

[0112] BR burner seal

[0113] C Outlet cone

[0114] D Diameter

[0115] D nozzle

[0116] DH nozzle holder

[0117] E Intake

[0118] F Fan

[0119] F1 , F2 fluid flow

[0120] FC fan housing

[0121] G Outer casing

[0122] Nozzle longitudinal axis

[0123] M Central axis / rotation axis

[0124] R combustion chamber ring

[0125] S rotor shaft

[0126] T (turbofan) engine

[0127] TT Turbine

[0128] V Compressor a Angle

Claims

Claims 1. Nozzle assembly for a combustion chamber (103) of an engine (T), comprising at least one nozzle (D) for injecting hydrogen into a combustion chamber (1030) of the combustion chamber (103), wherein the nozzle (D) has a nozzle body (DH) extending along a nozzle longitudinal axis (L) and a nozzle head (2) at one end of the nozzle body (DH), wherein at least one first air guide channel (12; 21) is provided to guide a first airflow towards the combustion chamber (1030) and via at least one first air outlet opening of the first air guide channel (12;21) to direct into the combustion chamber (1030), at least one fuel channel (22) is provided on the nozzle head (2) to direct hydrogen towards the combustion chamber (1030), and at least one second air guide channel (23) is provided to direct a second air flow towards the combustion chamber (1030) and to direct it into the combustion chamber (1030) via at least one second air outlet opening of the second air guide channel (22), wherein the fuel channel (22) has a fuel outlet opening for the hydrogen to be injected into the combustion chamber (1030), with reference to a radial direction perpendicular to the nozzle longitudinal axis (L), between the first and second air guide channels (12, 23;21, 23) with their first and second air outlet openings, characterized in that at least the second radially further outward air guide channel (23) is designed and provided for supplying an undistorted air flow into the combustion chamber (1030) and the fuel channel (22) is designed and provided for supplying an undistorted flow of hydrogen into the combustion chamber (1030).

2. Nozzle assembly according to claim 1, characterized in that at least the second radially further outward air guide channel (23) and the fuel channel (22) extend radially outwards at their respective channel ends.

3. Nozzle assembly according to claim 2, characterized in that the second radially further outward air guide channel (23) comprises a channel section (23B) having the second air outlet opening, which is at an angle (a) in the area from 30° to 60° to the nozzle longitudinal axis (L), and / or the fuel channel (22) includes a channel section (22B) having the fuel outlet opening, which runs at an angle (a) in the range of 30° to 60° to the nozzle longitudinal axis (L).

4. Nozzle assembly according to one of claims 1 to 3, characterized in that the fuel channel (22) and / or the second radially more outwardly located air guide channel (23) taper towards a respective channel end.

5. Nozzle assembly according to one of the preceding claims, characterized in that a central fuel supply line (11) is provided in the nozzle main body (1) for supplying hydrogen to the fuel channel (22).

6. Nozzle assembly according to claim 5, characterized in that at least one fluid guide is provided on the nozzle head (2) via which the hydrogen from the fuel supply line can be guided into the radially outer fuel channel (22).

7. Nozzle assembly according to claim 6, characterized in that at least a part of the fluid guidance is provided within a radially outward extending strut (24) of the nozzle head (2) which passes through a section of the first air guide channel (21).

8. Nozzle assembly according to one of the preceding claims, characterized in that a stabilizing body (10) is provided centrally at one nozzle end of the nozzle (D), which comprises a substantially planar end surface (100) facing the combustion chamber (1030).

9. Nozzle assembly according to claim 8, characterized in that the stabilizing body (10) defines at least a part of an inner wall of the first radially inner air guide channel (21) with an outer lateral surface.

10. Nozzle assembly according to claim 9, characterized in that the stabilizing body (10) defines with its outer surface an inner wall section (10B) extending radially outwards for the first air guide channel (21), such that the first air guide channel (21) extends radially outwards at its channel end.

11. Nozzle assembly according to claim 9 or 10, characterized in that the first radially inner air guide channel (21) tapers towards its channel end. A nozzle assembly according to any one of claims 8 to 11, characterized in that the substantially planar end face (100) of the stabilizer (10) facing the combustion chamber (1030) has a radial extension, relative to the nozzle longitudinal axis (L), which corresponds to at least twenty times, in particular at least thirty times, or twenty times, the channel height (a12) of the first air guide channel (21) at the first air outlet opening and / or the channel height (a22) of the second air guide channel (23) at the second air outlet opening and / or the channel height of the fuel channel (22) at the fuel outlet opening. A nozzle assembly according to any one of claims 8 to 12, characterized in that cooling is provided for the stabilizer (10). Nozzle assembly according to claim 6 or 7 and one of claims 8 to 13, characterized in that at least part of the fluid guidance is provided within the stabilizing body (10).Nozzle assembly according to claims 13 and 14, characterized in that the part of the fluid guide provided within the stabilizer body (10) is also provided for cooling the stabilizer body (10). Nozzle assembly according to claim 15, characterized in that, for impact cooling of the stabilizer body (10) with hydrogen, hydrogen is guided via the part of the fluid guide provided within the stabilizer body (10) against a rear wall (101) of the stabilizer body (10) facing away from the combustion chamber (1030). Nozzle assembly according to any one of claims 1 to 4, characterized in that the first air guide channel (12) is provided centrally on the nozzle main body (1) extending along the nozzle longitudinal axis (L) and a fuel supply line for the fuel channel (22) is provided in the nozzle main body (1) in a radially outer section of the nozzle main body (1).Nozzle assembly according to claim 17, characterized in that the first air guide channel (12) widens at its channel end having the first air outlet opening and forms a flow guide element (121) extending radially outwards for this purpose. Nozzle assembly according to claim 17 or 18, characterized in that at least one swirl element (120) for rotating the air is provided in the first air guide channel (12). the first air duct (12) provides airflow into the combustion chamber (1030).

20. Nozzle assembly according to claim 17 or 18, characterized in that a centrally arranged flow divider (122) is provided in the first air guide channel (12), via which an air flow in the first air guide channel (12) to a nozzle end of the nozzle (D) is divided into an inner and outer air guide channel part (12.1 , 12.2).

21. Nozzle assembly according to claim 20, characterized in that the flow divider (122) has a pipe section (122a) with a cross-sectional area that remains constant along the nozzle longitudinal axis (L) and a diffuser part (122b) adjoining the pipe section (122) towards the nozzle end, with a cross-sectional area that increases along the nozzle longitudinal axis (L).

22. Nozzle assembly according to claims 18 and 21, characterized in that the flow guide element (121) and the diffuser part (122b) border the outer air guide channel part (12.1), which points radially outwards.

23. Nozzle assembly according to one of claims 20 to 22, characterized in that at the nozzle end the part of the first air outlet defined by the inner air guide duct part (12.2) has a cross-sectional area which is at least a factor of 8, in particular at least a factor of 10 larger than the cross-sectional area of ​​that part of the first air outlet defined by the outer air guide duct part (12.1).

24. Nozzle assembly according to one of claims 20 to 23, characterized in that an axially flowable flow body (123) is provided centrally in the pipe section (122a).

25. Nozzle assembly according to one of the preceding claims, characterized in that the first and second air outlet openings and the fuel outlet opening are located in a radial plane perpendicular to the longitudinal axis (L) of the nozzle or are axially offset from each other.

26. Engine with at least one nozzle assembly according to one of the preceding claims.

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