NOZZLE DEVICE FOR ADDING FUEL TO A COMBUSTION CHAMBER OF A GAS TURBINE ASSEMBLY AND GAS TURBINE ASSEMBLY

Description

[0001] The invention relates to a nozzle device for adding fuel to a combustion chamber of a gas turbine arrangement according to the preamble of claim 1. The invention further relates to a gas turbine arrangement, in particular an engine of an aircraft.

[0002] A nozzle device of the type mentioned at the outset, with a nozzle main body for injecting the fuel into the combustion chamber and a nozzle holder with at least one fuel line for the flow connection between a distributor fuel line of a fuel distributor and the nozzle main body, is known, for example, from EP 0 071 420 A1.

[0003] A nozzle device according to the preamble of claim 1 is known from US 6,530,223 B1.

[0004] It is assumed (without written proof) to be known that a nozzle device of the type mentioned at the outset can have a throttle element arranged downstream of the distributor fuel line, in particular at the upstream (inlet-side) end of the fuel line, for throttling the fuel flow (mass flow) to a predetermined target quantity for addition via the nozzle main body into the combustion chamber during operation.

[0005] For low-density fuels, particularly gaseous fuels such as methane and / or hydrogen, high velocities of several hundred meters per second can occur when throttling the fuel flow by adjusting the required pressure drop across the nozzle device, e.g., by means of the throttle element. This causes disadvantages in the operation of the nozzle device, for example, a reduced residence time of the fuel within the combustion chamber and / or insufficient mixing combined with an unfavorable temperature profile at the combustion chamber outlet or turbine inlet.

[0006] The present invention is based on the object of providing a nozzle device and a gas turbine arrangement for optimized operation with gaseous fuels.

[0007] The problem is solved with respect to the nozzle device with the features of claim 1. Advantageous embodiments are specified in the dependent claims.

[0008] With regard to the gas turbine arrangement, the problem is solved with the features of claim 14.

[0009] To achieve the object, it is proposed with regard to the nozzle device that the throttle element comprises at least two stages arranged in series in terms of flow technology, each stage having at least one line section (in particular the fuel line) aligned along a central longitudinal axis and having a flow cross-section which is, for example, circular with a diameter (or elliptical or polygonal), and between the stages, if appropriate in each case, an expansion chamber is arranged, the flow cross-section of which is larger than the flow cross-section of the stage arranged upstream (immediately, without the interposition of a further stage), ie of the line section of the corresponding stage opening into the expansion chamber.

[0010] The throttle element thus comprises n stages Sx, with n at least two, with the individual stages Sx = 1...n arranged in series in terms of flow. The first stage is arranged furthest upstream, the nth stage furthest downstream, and the remaining stages are arranged in the corresponding order between them.

[0011] The line sections of the respective stages are, for example, cylindrical and / or rotationally symmetrical to their respective central longitudinal axes, and / or have a shape optimized for their arrangement relative to the other line sections. Existing edges can be rounded for a streamlined shape.

[0012] For example, each stage has exactly one line section.

[0013] The axial extent of the line sections and / or the expansion chambers is preferably as small as possible for a compact design; in the case of the line sections, it is designed like an orifice plate, but sufficiently large to achieve the desired effect with regard to pressure loss and / or expansion. For example, the axial extent of the respective line sections can be at least substantially equal. The axial extent is less than a diameter Ds of the fuel line downstream of the throttle element, e.g., less than half the diameter Ds.

[0014] The line sections of the respective stages have, for example, a circular or other-shaped, e.g., elliptical or polygonal, flow cross-section that is constant across the axial extent. With a circular flow cross-section, including the other lines (distributor fuel line, section of the fuel line downstream of the throttle element), the relative ratios of the flow cross-sections specified below also apply to the diameters of the lines, since the flow cross-sections depend solely on the diameters.

[0015] The fuel line downstream of the throttle element has, for example, at least immediately downstream of the throttle element and / or largely over its axial extent, a constant flow cross-section with the diameter Ds.

[0016] The proposed design of the throttle element allows the required throttling of the fuel flow to the specified target quantity to be achieved even with low-density fuels, particularly hydrogen, at lower flow velocities. This avoids significantly increased flow velocities and the associated disadvantages, enabling optimized operation of the nozzle device and / or the gas turbine assembly, even with, for example, hydrogen or hydrogen-containing fuels.

[0017] An effective throttling effect can be achieved if at least one of the, preferably all, line sections within the throttle element (i.e., the individual stages) has / have a smaller flow cross-section (with diameters Do1 ... Don) than the distributor fuel line (with diameter Dm) and / or the fuel line (immediately) downstream of the throttle element (with diameter Ds). Preferably, the flow cross-section of the distributor fuel line is larger than the flow cross-section of the fuel line downstream of the throttle element.

[0018] A flow-optimized throttling can be achieved if the first stage located furthest upstream has the largest flow cross-section of the existing stages, in particular the largest diameter.

[0019] In this context, it is particularly advantageous from a fluidic perspective if the stages arranged downstream of a stage (directly, without the interposition of another stage) each have an equal or smaller flow cross-section, in particular a diameter, than the respective (directly) upstream stage. In particular, for n ≥ 2, the following may apply: Dm > Ds > Do1 ≥ ... ≥ Don, e.g., Dm > Ds > Do1 ≥ Do2 ≥ Do3 (for n = 3) or Dm > Ds > Do1 ≥ Do2 (for n = 2).

[0020] In a preferred embodiment, the line sections are arranged at least partially coaxially with one another. The central longitudinal axes of the line sections and / or the central longitudinal axis of the fuel line arranged downstream of the throttle element are aligned.

[0021] The line section of at least one of the stages is arranged with its central longitudinal axis radially offset from the central longitudinal axis of at least one other stage and / or from the central longitudinal axis of the fuel line downstream of the throttle element, wherein the central longitudinal axes run parallel to one another, for example. The expansion chambers are arranged, in particular, for example, coaxially to the central longitudinal axis.

[0022] In this case, the offset of at least two line sections, preferably two (immediately) consecutive stages, can expediently be configured differently radially and / or in the circumferential direction. For example, two (or more) consecutive stages can be arranged (alternating) offset from one another in the circumferential direction by between 90° and 270°, e.g., by essentially 180°. The resulting alternating offset of the line sections advantageously contributes to increasing the pressure loss.

[0023] Advantageously, the offset can be designed such that the flow cross-sections of the line sections of at least two consecutive stages overlap little, e.g., by a maximum of 20% of the (possibly smaller) flow cross-section, or not at all with respect to their radial position and / or position in the direction of rotation, i.e., the flow cross-sections have at least largely different radial positions and / or positions in the direction of rotation. Viewed in the axial direction, a geometric overlap of consecutive flow cross-sections is thus avoided or at least minimized. In this way, it can be prevented that individual flow threads shoot axially through the throttle element and thus reduce the throttling effect.In particular, it may be expedient for the individual flow cross-sections to be configured in a shape other than circular or polygonal, with a shape optimized for such a staggered arrangement relative to the other line sections, e.g., semicircular, elliptical, and / or crescent-shaped. The shapes of the flow cross-sections of the successive stages may, for example, be congruent, or each have a different shape favorable for this configuration, e.g., a combination of crescent and circular. The central longitudinal axes of the line sections, in particular, each run through the centroids of the respective flow cross-sections.

[0024] A favorable throttling effect can further be achieved by arranging the line section of at least one stage with its central longitudinal axis inclined at an angle relative to the central longitudinal axis of the line section of another stage and / or the central longitudinal axis of the fuel line downstream of the throttle element. The angle can be constant (resulting in a constant gradient) or variable (resulting in a curvature). The angle is preferably 45° or less, e.g., 30° or less.

[0025] In this case, several (particularly directly) consecutively arranged line sections of several stages can expediently be arranged with their central longitudinal axes inclined at an angle relative to the central longitudinal axis of the fuel line downstream of the throttle element, wherein the inclinations, particularly in their orientations with respect to the direction of rotation, alternate. For example, the inclinations can have the same, particularly constant, angle and / or the central longitudinal axes of successive stages can point in a different direction with respect to the direction of rotation, e.g., offset from one another by between 90° and 270°, e.g., by substantially 180°.

[0026] In a variant advantageous from a manufacturing perspective, the throttle element comprises, or is designed as, a particularly cylindrical, e.g., monolithic, hollow body, which is fastened to or in the nozzle holder with a fluid-tight seal. The hollow body preferably comprises at least parts of a fastening means and / or a fastening structure, e.g., a thread for a screw connection. In this way, the throttle element can advantageously be manufactured separately and subsequently assembled independently of the nozzle device, in particular the nozzle holder. A monolithic hollow body comprising the entire throttle element can be manufactured, in particular, by means of an additive manufacturing process (3D printing).

[0027] In a design variant that is advantageous in terms of manufacturing and assembly technology, the throttle element comprises or is formed from at least two individual elements, wherein in particular each individual element has at least the line section of one stage. The individual elements preferably comprise line sections and / or expansion chambers in such a way that conventional production of the throttle element or the individual elements can take place without additive manufacturing processes, e.g., by means of a machining process such as turning and / or drilling. During installation, the individual elements are preferably sealed in a fluid-tight manner against one another and / or against the rest of the nozzle device. This design variant also offers advantages in terms of interchangeability, e.g., when designing the throttle element on a test bench, wherein the individual elements can be replaced individually if necessary.

[0028] In one design variant, if several expansion chambers are present, their flow cross-sections, in particular their diameters, can be of the same size (and congruent).

[0029] In particular in this context, the flow cross-sections, in particular the diameters, of the expansion chambers can correspond (in shape and / or size) to the flow cross-section, in particular the diameter, of the fuel line arranged downstream of the throttle element.

[0030] The invention will be explained in more detail below using exemplary embodiments with reference to the drawings. They show: Fig. 1 shows a nozzle device with a throttle element for throttling a fuel flow to a predetermined target quantity according to the prior art in a schematic representation in longitudinal section, Fig. 2 shows a proposed nozzle device with the throttle element comprising three stages which have a smaller diameter one after the other in the direction of flow, in a schematic representation in longitudinal section, Fig. 3 shows a further embodiment of the proposed nozzle device with the throttle element comprising three stages with the same diameter in a schematic representation in longitudinal section, Fig. 4 shows a further embodiment of the proposed nozzle device with the throttle element comprising two stages which have a smaller diameter one after the other in the direction of flow, in a schematic representation in longitudinal section,5 shows a further embodiment of the proposed nozzle device with the throttle element comprising three individual elements and three stages in a schematic representation in longitudinal section, Fig. 6 shows a further embodiment of the proposed nozzle device with the throttle element comprising three stages with radially offset line sections in a schematic representation in longitudinal section, Fig. 7 shows a further embodiment of the proposed nozzle device with the throttle element comprising three stages with inclined line sections in a schematic representation in longitudinal section and Fig. 8A, B, C each show exemplary shapes of flow cross sections of two, in particular, successive line sections in a schematic representation in plan view.

[0031] Fig. 1 shows a schematic representation in longitudinal section of a nozzle device 1 for adding fuel 14 into a combustion chamber of a gas turbine arrangement, in particular the engine of an aircraft. The nozzle device 1 has a Fig. 1 indicated nozzle main body 1a, through which fuel 14 is pumped during operation by means of nozzle openings (in Fig. 1 not shown) is injected into the combustion chamber.

[0032] The Fig. 1 The nozzle device 1 shown is designed in particular for adding liquid fuels, e.g. kerosene.

[0033] Furthermore, the nozzle device 1 has a nozzle holder 1b with, here for example, a fuel line 2. In the installed state, the fuel line 2 forms a flow connection between a connection 4 of a fuel distributor (fuel manifold), with a fuel supply line 3, and the nozzle main body 1a. The fuel line 2 is aligned at least in sections along a central longitudinal axis M, wherein the central longitudinal axis M forms the axis of symmetry. The fuel line 2 has, at least in a section arranged downstream of a throttle element 7, in particular a circular flow cross-section with a diameter Ds, which is delimited by a wall 20 of the fuel line 2.

[0034] Fig. 1 shows the connection 4 with the fuel supply line 3. The fuel supply line 3 has, at least directly upstream of the fuel line 2, in particular a circular flow cross-section with a diameter Dm, wherein the flow cross-section of the fuel supply line 3 is larger than the flow cross-section of the fuel line 2. With the preferably circular design of the flow cross-section, Dm > Ds therefore applies.

[0035] The fuel supply line 3 and the nozzle holder 1b are fluid-tightly connected to each other by a connecting arrangement 5. The connecting arrangement 5 can, for example, be designed as a screw connection with a nut and a corresponding thread.

[0036] At the upstream (inlet-side) end of the fuel line 2, the throttle element 7 is arranged, which during operation throttles the fuel flow (mass flow) flowing from the fuel supply line 3 into the nozzle device 1 to a predetermined target quantity required for the operation of the combustion chamber.

[0037] The throttle element 7 is designed, for example, as a cylindrical hollow body 70, which is inserted, in particular, in a form-fitting manner, into a corresponding cylindrical recess 15 in the wall 20. Another design would also be possible, e.g., with an arrangement between the connection 4 and the nozzle holder 1b.

[0038] For fluid-tight sealing, a circumferential ring seal 13 is provided on the outside of the annular body 70 as a sealing means, for example. The upstream end of the hollow body 70 essentially flushes with the upstream end of the wall 20. For axial fixation, a wall of the fuel supply line 3 radially overlaps the hollow body 70.

[0039] The hollow body 70 comprises a line section 6 of the fuel line 2 arranged within the throttle element 7, which is formed in particular by a central, longitudinally oriented cylindrical bore 60 extending longitudinally through the hollow body 70. The bore 6 is arranged with a central longitudinal axis M1 coaxial with the section of the fuel line 2 arranged downstream of the throttle element 7, wherein the central longitudinal axis M1 lies on the central axis M.

[0040] The line section 6 of the throttle element 7 has a smaller flow cross-section than the section of the fuel line 2 arranged downstream of the throttle element 7. The flow cross-section is preferably circular and has a diameter Do. With the preferably circular design of the remaining flow cross-sections, Dm > Ds > Do applies. In this case, the diameters of the flow cross-sections are related to one another by way of example. If the flow cross-sections are not circular, the relative relationships of the relevant sections apply (also with regard to the embodiments according to Fig. 2 bis Fig. 8 ) generally for the relevant flow cross-sections.

[0041] During operation, fuel 14 flows into the nozzle device 1 via the connection 4. The fuel flow first passes through the throttle element 7, in which, due to the reduction of the flow cross-section, a pressure drop resulting in a flow resistance is generated such that the desired amount of fuel 14 is supplied to the nozzle main body 1a through the fuel line 2.

[0042] For fuels with low density (gaseous fuels such as methane and / or hydrogen), high speeds of several hundred meters per second can disadvantageously occur to achieve the required pressure drop.

[0043] To avoid this, a nozzle device 1 with a modified throttle element 7 is proposed for fuels with low density, in particular hydrogen. A variant of the modified throttle element 7 is shown in Fig. 2 shown.

[0044] The Fig. 2 The throttle element 7 shown has at least two, in Fig. 2 For example, three stages S1, S2, S3 arranged in series in terms of flow. Each stage S1, S2, S3 has a line section 8, 9, 10 of the fuel line 2 aligned along a respective central longitudinal axis M1, M2, M3, with a respective, in particular constant, flow cross-section. The line sections 8, 9, 10 are each formed, for example, by a, in particular cylindrical, bore 80, 90, 100. The flow cross-sections are each preferably circular, with diameters Do1, Do2, Do3.

[0045] An expansion chamber 11 is arranged between the first stage S1 and the second stage S2, which follows in the direction of flow (immediately, without the interposition of a further stage). An expansion chamber 12 is arranged between the second stage S2 and the third stage S3, which follows in the direction of flow (immediately, without the interposition of a further stage). The expansion chambers 11, 12 each have a larger flow cross-section than the respective immediately upstream stage S1, S2. For example, the flow cross-sections of the expansion chambers 11, 12 correspond to one another and / or at least substantially to the flow cross-section of the section of the fuel line 2 downstream of the throttle element 7, wherein their diameter is approximately equal to the diameter Ds.

[0046] The axial extent of the expansion chambers 11, 12 is, in the present case, for example, smaller than the axial extent of the line sections 8, 9, 10, such that an expansion effect is achieved, but as small as possible for the most compact design of the throttle element 7.

[0047] The axial extension of the line sections 8, 9, 10 of the individual stages S1, S2, S3 is, in this example, at least substantially identical. The axial extension is, for example, less than the diameter Ds, in particular less than half the diameter Ds.

[0048] The throttle element 7, which comprises the stages S1, S2, S3 and the expansion chambers 11, 12, is in Fig. 2 For example, it is manufactured monolithically from a single piece. Production can be achieved, for example, using an additive manufacturing process (3D printing).

[0049] The line sections 8, 9, 10 are in Fig. 2 For example, they are arranged coaxially to the section of the fuel line 2 downstream of the throttle element 7, with their respective central longitudinal axis M1, M2, M3 lying on the central longitudinal axis M.

[0050] In Fig. 2 For example, the downstream stages S2, S3 each have a smaller flow cross-section than the stages S1, S2 arranged directly upstream. This results in a step-by-step reduction of the flow cross-section within the fuel line 2 via the stage arrangement within the throttle element 7. In particular, the furthest upstream, first stage S1 has the largest flow cross-section, with the largest diameter Do1. The subsequent, second, stage S2 has a smaller flow cross-section, with the smaller diameter Do2. The subsequent, third, stage S3 has the smallest flow cross-section, with the smallest diameter Do3. In summary, therefore, in the Fig. 2 In the embodiment variant of the nozzle device 1 shown, the ratio of the diameters of the individual lines relative to one another is according to the rule Dm > Ds > Do1 > Do2 > Do3. In general form with n stages, for n ≥ 2: Dm > Ds > Do1 > ... > Don.

[0051] Fig. 3 shows a further embodiment of the nozzle device 1 with a throttle element 7 comprising three stages S1, S2, S3. Compared to the Fig. 2 In the variant shown, the throttle device 7 differs according to Fig. 3 in that all stages S1, S2, S3 have the same flow cross-section, in particular the same diameters Do1, Do2, Do3. Here, too, expansion chambers 11, 12 are arranged between the stages S1, S2 and S2, S3.

[0052] In summary, the Fig. 3 In the embodiment variant of the nozzle device 1 shown, the ratio of the diameters of the individual lines is Dm > Ds > Do1 = Do2 = Do3. In general terms with n stages, for n ≥ 2: Dm > Ds > Do1 = ... = Don.

[0053] Fig. 4 shows a further embodiment of the nozzle device 1 with a throttle element 7 comprising, here, for example, two stages S1, S2. The expansion chamber 11 is arranged between the two stages S1, S2. The remaining embodiment (arrangement of the line sections 8, 9, axial extension of the line sections 8, 9 and the expansion chamber 11) corresponds Fig. 4 , apart from the 2-stage training, which in Fig. 2 The training variant shown, where the flow cross-section of the first stage S1 is smaller than the flow cross-section of the second stage S2, so that: Dm > Ds > Do1 > Do2 applies. It would also be possible for the two-stage training to train the stages S1 and S2 according to the rule Dm > Ds > Do1 = Do2.

[0054] Fig. 5 shows a variant of the nozzle device 1 with a throttle element 7, which, with regard to the design and arrangement of the line sections 8, 9, 10 and the expansion chambers 11, 12, is exemplary of the one shown in Fig. 2 shown design variant. In particular, the diameters of the individual lines are designed according to the specification Dm > Ds > Do1 > Do2 > Do3.

[0055] In contrast to the Fig. 2 In the embodiment shown, the throttle element 7 has a plurality of individual elements 7a, 7b, 7c, or in the present case is formed from the individual elements 7a, 7b, 7c. The individual elements 7a, 7b, 7c are each formed from cylindrical hollow bodies which, when assembled, form the hollow body 70. Preferably, each individual element 7a, 7b, 7c has the line section 8, 9, 10 of a stage S1, S2, S3. The expansion chamber 11 is assigned, for example, to the individual element 7a with the stage S1. The expansion chamber 12 is assigned, for example, to the individual element 7b with the stage S2. Such a design of the throttle element 7 results in particular in advantages during manufacture and / or installation of the throttle element 7 and / or allows simple modification of the throttle element 7, e.g. during design of the nozzle device 1 or the throttle element 7 in test bench operation.

[0056] Fig. 6 shows a further embodiment of the nozzle device 1 with a throttle element 7 comprising, for example, the three stages S1, S2, S3. Based on the embodiment according to Fig. 2 The flow cross sections of stages S1, S2, S3 are designed according to the rule Dm > Ds > Do1 > Do2 > Do3.

[0057] In contrast to the Fig. 2 shown embodiment are in Fig. 6 The line sections 8, 9, 10 are arranged with their respective central longitudinal axes M1, M2, M3 radially offset from the central longitudinal axis M. The offset of the central longitudinal axes M1, M2, M3 is different for each of the (immediately) successive stages S1, S2, S3; in the present example, they are alternately offset to the two radially opposite sides of the central longitudinal axis M (e.g., by approximately 180° in the circumferential direction). The expansion chambers 11, 12 are arranged, in particular, coaxially to the central longitudinal axis M.

[0058] Fig. 7 shows a further embodiment of the nozzle device 1 with a throttle element 7 comprising, for example, the three stages S1, S2, S3. Based on the embodiment according to Fig. 2 The flow cross sections of stages S1, S2, S3 are designed according to the rule Dm > Ds > Do1 > Do2 > Do3.

[0059] In contrast to the Fig. 2 shown embodiment are in Fig. 7 the line sections 8, 9, 10 are arranged with their respective central longitudinal axes M1, M2, M3 inclined relative to the central longitudinal axis M at an exemplary constant angle α1, α2, α3. The inclinations are preferably less than 45°, e.g. less than 30° relative to the central longitudinal axis M. The inclinations of the central longitudinal axes M1, M2, M3 alternate for the (immediately) successive stages S1, S2, S3 in their orientations with respect to the direction of rotation. In the present case, the central longitudinal axes M1, M2, M3 lie, for example, in a common plane, but are inclined or aligned on opposite sides with respect to the central longitudinal axis M, i.e. with an offset in the direction of rotation of 180°. The angles α1, α2, α3 have, for example, the same amount.

[0060] Fig. 8A, Fig. 8B und Fig. 8C show in addition to Fig. 6 in a plan view of the line sections 8, 9 of the respective stage S1, S2, each showing exemplary shapes and arrangements which can have offset flow cross-sections of two, in particular successive, line sections 8, 9. In this case, the offset is designed in such a way that the flow cross-sections of the line sections 8, 9 of the two successive stages S1, S2 do not overlap with regard to their radial position and / or position in the direction of rotation, i.e. the flow cross-sections, arranged one behind the other in the axial direction, have different radial positions and positions in the direction of rotation. Viewed in the axial direction, this avoids a geometric overlap of successive flow cross-sections. This prevents individual flow threads from shooting axially through the throttle element 7 without deflection and thus reducing the throttling effect.

[0061] In Fig. 8A The flow cross sections are semicircular and congruent to each other. Fig. 8B The flow cross sections are elliptical and congruent to each other. Fig. 8C For example, the flow cross-sections are designed differently, with one flow cross-section being circular and one flow cross-section being sickle-shaped.

[0062] The individual features of the embodiments according to Fig. 2 bis Fig. 8 can of course be combined in different ways.

[0063] In summary, the design and / or arrangement of stages S1, S2 and, if applicable, S3, in particular the line sections 8, 9 and, if applicable, 10, in the Fig. 2 bis Fig. 7 With the exemplary embodiments of the throttle element 7 shown, an increased pressure drop per length of the throttle element 7 can be achieved without reducing the diameter of the line sections 8, 9, and possibly 10 to such an extent that excessively high velocities occur when using gaseous fuels, in particular hydrogen. The different design variants of the nozzle device 1, in particular of the throttle element 7, can influence the flow pattern, in particular within the throttle device 7. Thus, with the proposed nozzle device 1, a gas turbine arrangement can be optimized, in particular with regard to operation with hydrogen. Bezugszeichenliste

[0064] 1Nozzle device 1aNozzle main body 1bNozzle holder 2Fuel line 20Wall 3Fuel supply line 4Connection 5Connecting means 6Line section 60Bore 7Throttle element 70Hollow body 7aIndividual element 7bIndividual element 7cIndividual element 8Line section 80Bore 9Line section 90Bore 10Line section 100Bore 11Relief chamber 12Relief chamber 13Ring seal 14Fuel 15Recess DmDiameter of distributor fuel line DsDiameter of fuel line DoDiameter of line section Do1Diameter of line section Do2Diameter of line section Do3Diameter of line section MCenter longitudinal axis M1Center longitudinal axis M2Center longitudinal axis M3Center longitudinal axis S1Step S2Step S3Step α1Angle α2Angle α3Angle

Claims

1. Nozzle device (1) for adding gaseous fuel (14) to a combustor of a gas turbine assembly, comprising - a nozzle main body (1a) with nozzle openings for injecting the fuel into the combustor, and - a nozzle holder (1b) with at least one fuel line (2) for flow connection between a distributor fuel line (4) of a fuel distributor (3) and the nozzle main body (1a), wherein the fuel line (2) is aligned at least in sections along, and in particular symmetrically to, a central longitudinal axis (M), and with a throttle element (7) arranged downstream of the distributor fuel line (4), in particular at the upstream end of the fuel line (2), for throttling the fuel flow to a predetermined target amount, wherein - the throttle element (7) comprises at least two stages (S1, S2, S3) arranged in series in terms of flow, wherein each stage (S1, S2, S3) has at least one line section (8, 9, 10) which is aligned along a central longitudinal axis (M1, M2, M3) and has a flow cross section, wherein in each case, there is one expansion chamber (11, 12) arranged between the stages (S1, S2, S3), the flow cross section of which is greater than the flow cross section of the stage (S1, S2) arranged upstream thereof, characterized in that - an axial extent of the line sections (8, 9, 10) is less than a diameter (Ds) of the fuel line (2) downstream of the throttle element (7), and - the line section (8, 9, 10) of at least one stage (S1, S2, S3) is arranged with its central longitudinal axis (M1, M2, M3) radially offset from the central longitudinal axis (M1, M2, M3) of at least one other stage (S1, S2, S3) and / or from the central longitudinal axis (M) of the fuel line (2) downstream of the throttle element.

2. Nozzle device (1) according to claim 1, characterized in that at least one of the line sections (8, 9, 10) within the throttle element (7) has a smaller flow cross section than the distributor fuel line (4) and / or the fuel line (2) downstream of the throttle element.

3. Nozzle device (1) according to claim 1 or 2, characterized in that the first stage (S1) arranged furthest upstream has the largest flow cross section of the existing stages (S1, S2, S3).

4. Nozzle device (1) according to one of the preceding claims, characterized in that the stages (S1, S2, S3) arranged downstream of a stage (S1, S2) in terms of flow in each case have an identical or smaller flow cross section than the respective stage (S1, S2) arranged upstream.

5. Nozzle device (1) according to one of the preceding claims, characterized in that the line sections (8, 9, 10) are arranged at least partially coaxially to one another.

6. Nozzle device (1) according to one of the preceding claims, characterized in that the offset of at least two line sections (8, 9, 10), preferably of two successive stages (S1, S2, S3), is configured differently radially and / or in the direction of rotation, wherein, for example, at least two successive stages (S1, S2, S3) are arranged offset from one another in the direction of rotation, optionally in each case, by between 90° and 270°, e.g. by substantially 180°.

7. Nozzle device (1) according to claim 6, characterized in that the offset is designed such that the flow cross sections of the line sections (8, 9, 10) of at least two successive stages (S1, S2, S3) overlap only slightly, e.g. by a maximum of 20% of the flow cross section, or do not overlap at all with respect to their radial position and / or position in the direction of rotation.

8. Nozzle device (1) according to one of the preceding claims, characterized in that the line section (8, 9, 10) of at least one of the stages (S1, S2, S3) is arranged with its central longitudinal axis (M1, M2, M3) inclined at an angle (α1, α2, α3) downstream of the throttle element (7) with respect to the central longitudinal axis (M1, M2, M3) of the line section (8, 9, 10) of another stage (S1, S2, S3) and / or the central longitudinal axis (M) of the fuel line (2).

9. Nozzle device (1) according to claim 8, characterized in that a plurality of line sections (8, 9, 10), arranged one behind the other, of a plurality of stages (S1, S2, S3) are arranged with their central longitudinal axes (M1, M2, M3) inclined at the angle (α1, α2, α3) with respect to the central longitudinal axis (M) of the fuel line (2) downstream of the throttle element (7), wherein the inclinations, in particular in their orientations with respect to the direction of rotation, alternate in each case.

10. Nozzle device (1) according to one of the preceding claims, characterized in that the throttle element (7) comprises or is formed as a hollow body (70) which is in particular cylindrical, for example monolithic, and is fastened to or in the nozzle holder (1b) in a fluid-tight manner.

11. Nozzle device (1) according to one of the preceding claims, characterized in that the throttle element (7), in particular the hollow body (70), comprises at least two individual elements (7a, 7b, 7c) or is formed therefrom, wherein in particular one individual element (7a, 7b, 7c) in each case has at least the line section (8, 9, 10) of a stage (S1, S2, S3).

12. Nozzle device (1) according to one of the preceding claims, characterized in that in the presence of a plurality of expansion chambers (11, 12), their flow cross-sections, in particular their diameters, are of the same size.

13. Nozzle device (1) according to claim 12, characterized in that the flow cross sections, in particular the diameters, of the expansion chambers (11, 12) correspond to the flow cross section, in particular the diameter (Ds), of the fuel line (2) arranged downstream of the throttle element (7).

14. Gas turbine assembly having a turbine assembly and having at least one nozzle device (1) according to one of the preceding claims.