INJECTOR DEVICE FOR AN ENGINE DEVICE, ENGINE DEVICE AND AIR AND / OR SPACE VEHICLE

Description

[0001] The present invention relates to an injector device for an engine device for introducing a fluidic, in particular liquid, fuel and a fluidic, in particular liquid, oxidizing agent into a combustion chamber of the engine device, which injector device defines a longitudinal axis and comprises at least one first injection element, which is designed in the form of a first fluid channel for fluidically connecting a first collection space for the fluidic oxidizing agent and the combustion chamber, and at least one second injection element, which is designed in the form of a second fluid channel for fluidically connecting a second collection space for the fluidic fuel and the combustion chamber,wherein at least one first resonator element is assigned to the at least one first injection element and / or wherein at least one second resonator element is assigned to the at least one second injection element and wherein the at least one first resonator element is tuned to a natural frequency of the assigned at least one first injection element and / or that the at least one second resonator element is tuned to a natural frequency of the assigned at least one second injection element,.,

[0002] Furthermore, the present invention relates to an engine device, in particular for an aircraft and / or spacecraft, which engine device comprises a combustion chamber with a nozzle and an injection device arranged opposite the nozzle, wherein acoustic natural vibrations are damped in at least one first injection element and / or wherein acoustic natural vibrations are damped in at least one second injection element, wherein at least one first resonator element is assigned to the at least one first injection element and / or wherein at least one second resonator element is assigned to the at least one second injection element, wherein the at least one first resonator element is tuned to a natural frequency of the assigned at least one first injection element and / or wherein the at least one second resonator element is tuned to a natural frequency of the assigned at least one second injection element.

[0003] Furthermore, the present invention relates to an aircraft and / or spacecraft having an engine device and a fuel tank for accommodating a fluidic, in particular liquid, fuel.

[0004] Furthermore, the present invention relates to a method for operating an engine device, in which method a fluidic, in particular liquid, fuel and a fluidic, in particular liquid, oxidizing agent are introduced into a combustion chamber of the engine device by means of an injector device, which injector device comprises at least one first injection element for fluidically connecting a first collection space for the fluidic oxidizing agent and the combustion chamber, and at least one second injection element for fluidically connecting a second collection space for the fluidic fuel and the combustion chamber.

[0005] Propulsion devices of the type described above are known, for example, in the form of liquid-propellant rocket engines. In these, a fuel, also referred to as propellant, and an oxidizer, also referred to as oxidizer, are injected into the combustion chamber and reacted there. Combustion chambers of such engines typically define a cylindrical volume defined downstream by a convergent nozzle with a sonic passage in the narrowest cross-section. Upstream of the combustion chamber, the fuel and oxidizer are injected, for example, through so-called injector plates. So-called coaxial injection elements are frequently used, particularly with cryogenic propellants such as liquid hydrogen combined with an oxidizer in the form of liquid oxygen, or with a combination of liquid methane with liquid oxygen.The liquid oxygen is injected centrally through a tube and the fuel is injected at high speed through a narrow annular gap formed around the tube.

[0006] One of the greatest risks in the development and operation of a rocket engine is the occurrence of high-frequency, thermoacoustic combustion instabilities. High-frequency combustion instabilities arise, for example, from the interaction of combustion chamber acoustics with fluctuations in the heat release rate of the flame produced during combustion. This leads to the amplification of acoustic pressure fluctuations if the fluctuation component of the heat release rate is in phase with the pressure fluctuations.

[0007] Due to the high power density in a rocket combustion chamber, even a small fraction of the converted chemical energy transferred into the acoustic field is sufficient to generate rapidly increasing, high pressure amplitudes up to the order of magnitude of the static combustion chamber pressure. These pressure amplitudes can lead to mechanical or thermal failure of a combustion chamber wall surrounding the combustion chamber.

[0008] To solve this problem, so-called baffles are inserted into the combustion chamber. These are, in particular, extended injection elements or cooled walls that extend into the combustion chamber from an injector plate interspersed with the injection elements. The baffles are intended to break the combustion chamber symmetry or, by creating vortices during flow over the walls, reduce the acoustic energy of transverse modes through dissipation.

[0009] Acoustic resonators, such as λ / 4 resonators or Helmholtz resonators, are also known. These are installed in the combustion chamber wall to dampen pressure fluctuations caused by combustion instabilities.

[0010] However, the baffles described are only capable of damping transverse eigenmodes of the combustion chamber. They have no effect on longitudinal eigenmodes. Furthermore, they require complex cooling, as the baffles extend into the combustion chamber volume, where temperatures of up to 3600 K prevail. Such baffles are typically developed using a trial-and-error approach. As a result, their damping properties are difficult to predict in advance, and proving their functionality requires expensive testing during the development process of an engine device.

[0011] Acoustic resonators can theoretically be designed for any frequency and thus any combustion chamber mode, provided the speed of sound in the resonator volume is known. However, installing the resonators in the combustion chamber wall is problematic. With regeneration cooling of the combustion chamber, the resonators must be installed between the cooling channels in the combustion chamber. However, there is limited space available there, so the cooling channels must be routed around the resonators, which is a complex process. This generally reduces the cooling efficiency of the combustion chamber wall in the area of ​​the resonators. Furthermore, manufacturing the combustion chamber wall with resonators is significantly more complex than without.

[0012] Another problem with resonators in the combustion chamber wall is that the speed of sound in the resonator is not clearly defined. Through the opening of the resonators towards the combustion chamber, combustion gases enter a resonator volume defined by the resonator. Depending on the operating point of the engine, the flow field in the combustion chamber, and the position of the resonators relative to the injection elements, different gas compositions can be present in the resonator. Furthermore, the temperature in the resonators is also unknown. It lies in a range between two extreme values, which are determined by the combustion temperature on the one hand and the temperature of the cooling fluid in the cooling channels of the combustion chamber wall on the other. If the temperatures of the gas composition in the resonator are unknown, the speed of sound in the resonators cannot be accurately predicted.Therefore, resonators in the combustion chamber wall can only be designed through complex tests and simulations of combustion and cooling. Furthermore, it must be considered that the speeds of sound in the combustion chamber and the resonators do not react uniformly to changes in an engine operating point. Therefore, the resonators are strictly speaking designed for only one combustion chamber mode for a specific operating point. During engine startup or shutdown, the resonators are not adapted, which can lead to instabilities despite the resonators acting as damping elements.

[0013] An injection device for a rocket is known from JP 2010 236386 A. EP 3 034 945 A1 discloses a fuel line for a gas turbine with a damper. Injection elements are described in WO 2013 / 004949 A1. WO 2019 / 067114 A1 relates to fuel injector assemblies for gas turbine engines. A device for damping combustion chamber vibrations in liquid rocket engines is known from FR 2 570 129 A1. WO 2005 / 100858 A1 deals with the damping of vibrations in a combustion chamber using resonators. An injector head with a resonator for a gas turbine engine is disclosed in US 2018 / 163967 A1.

[0014] It is therefore an object of the present invention to improve an injector device for an engine device, an engine device and an aircraft and / or spacecraft such that an amplification of acoustic pressure fluctuations in a combustion chamber can be minimized or completely avoided.

[0015] This object is achieved according to the invention in an injector device for an engine device of the type described at the outset in that the at least one first resonator element and the first collecting chamber are fluidically connected to one another via a first flushing channel and / or that the at least one second resonator element and the second collecting chamber are fluidically connected to one another via a second flushing channel, so that the fluid flowing through the injection elements also flows at a low flow velocity through the respective resonator element, whereby it can be ensured that the same conditions prevail in the respective resonator element at all times as in the injection element to be damped.

[0016] The at least one first resonator element and the at least one second resonator element form damping elements to dampen possible pressure fluctuations in the respective injection element. In this way, acoustics in the injection elements can be dampened to prevent injector-coupled combustion instabilities in the combustion chamber. It is fundamentally possible to dampen either the injection of the fuel or the injection of the oxidant, or the injection of both the fuel and the oxidant, using appropriate resonator elements. In particular, if a large number of injection elements are provided, different injector eigenmodes can also be dampened in a simple manner. This can be achieved by appropriately different designs of the first and / or second resonator elements. In particular, a position of the respective injection element can also be utilized.For example, certain injection elements, where coupling with tangential modes of the combustion chamber is expected, can be damped accordingly. Furthermore, injection elements, where coupling with a radial combustion chamber mode is expected, can also be damped accordingly by designing the associated resonator element(s). Furthermore, the proposed assignment of the resonator elements to the injection elements makes it possible to arrange them, in particular, spatially close to the injection elements, for example, in an injection head or an injector plate of the injector device. This is subject to less thermal stress than the combustion chamber. The proposed design eliminates the need to provide resonators in the combustion chamber wall, particularly in the case of injector-coupled instabilities, thus simplifying the design of the cooling channels in the combustion chamber wall.This simplifies both the design and manufacture of the combustion chamber as a whole. The assignment of the resonator elements to the injection elements enables, in particular, a spatial arrangement in the injector head, which is often made of materials such as stainless steel or nickel-based alloys. This makes it possible, in particular, to form the injector head using additive manufacturing processes such as selective laser melting. This simplifies the formation of acoustic resonators in the injector head. Furthermore, the damping of annular injection elements is also fundamentally possible in a simple manner. Finally, the direct assignment of resonator elements to the injection elements also allows them to be retrofitted to existing combustion chambers, since the combustion chamber wall itself does not need to be modified. Only changes to the injector device are required.Conventional combustion chambers can thus be easily retrofitted with the injector devices further developed as proposed. Fluidic fuels or fluidic oxidizers are in particular liquid and / or gaseous fuels or liquid and / or gaseous oxidizers. For example, liquid fuel can be carried on board an aircraft, and the oxidizer can be extracted from the atmosphere in the form of gaseous oxygen and supplied to the engine device. It is advantageous if the at least one first resonator element and the first plenum are fluidly connected to one another via a first purge channel and / or if the at least one second resonator element and the second plenum are fluidly connected to one another via a second purge channel.Providing such purge channels has the particular advantage of preventing compressed residual gases from remaining in the respective resonator element. The purge channels ensure, in particular, that the fluid flowing through the injection elements also flows at a low flow velocity through the respective resonator. This ensures, in particular, that the same conditions prevail in the respective resonator at all times as in the injection element to be damped. This has a particular advantage in that the same speed of sound in the injection element as in the resonator element forming a damping element makes the design of the geometry of the resonator element independent of the speed of sound and thus also independent of the respective fluid. Due to the comparatively low flow velocity and Mach number in the injection element, these can be neglected.Therefore, only the dimensions of the resonator elements need to be designed for the respective injection elements. In other words, this means that when the injection element and the associated resonator element are only linked by their geometry, the resonator elements no longer only dampen the eigenmodes of the combustion chamber for a defined operating point, but can dampen the eigenfrequencies of the injection elements for all conceivable operating conditions. A much more complex simulation of the combustion chamber acoustics with combustion can therefore be eliminated, and the resonator elements can be designed using an acoustic modal analysis. Fine-tuning of the resonator elements can thus also be carried out using a substitute fluid such as air. This can drastically reduce the design effort compared to hot-gas tests for resonator elements in the combustion chamber.

[0017] It is advantageous if the at least one first resonator element is fluidly connected to the at least one first injection element and / or if the at least one second resonator element is fluidly connected to the at least one second injection element. This configuration makes it possible, in particular, for the fuel to reach the at least one first resonator element and / or the oxidant to reach the at least one second resonator element. This can in particular ensure that almost identical conditions, i.e. an identical pressure and an identical temperature, prevail in the injection element and in the associated resonator element. This particularly simplifies the design of the resonator elements since ultimately only their volume needs to be taken into account. The design of the resonator elements is thereby greatly simplified and becomes primarily independent of the current power of the combustion chamber during operation.The respective resonator element can be designed for a desired frequency of the associated injection element to be damped using simple methods. Since the fluid properties in the injector and the resonator are identical or essentially identical due to their design, a modal analysis is sufficient to determine the resonator geometry. Complex, time-consuming, and uncertain combustion modeling and flow simulation in the combustion chamber are not required. This allows, for example, the functionality of the injector device and the combustion chamber to be validated using simple cold gas experiments, since the mode of operation and function of the injector device is independent of the fluid used due to its design.

[0018] It is advantageous if the at least one first resonator element comprises a first resonator cavity which defines a first resonator volume, and if a first resonator channel fluidically connects the at least one first injection element and the first resonator cavity, and / or if the at least one second resonator element comprises a second resonator cavity which defines a second resonator volume, and if a second resonator channel fluidically connects the at least one second injection element and the second resonator cavity. The fluidic connection of the resonator elements to the injection elements through the corresponding resonator channels makes it possible, in particular, to ensure that the properties of the fuel in the respective injection element and in the associated resonator element, and correspondingly also of the oxidant in the respective injection element and in the associated resonator element, are identical.Thus, the desired effect of the resonator elements is independent of the respective operating point of the engine device.

[0019] It is advantageous if the first resonator channel defines a first resonator channel volume and the first resonator channel volume is smaller than the first resonator volume, and / or if the second resonator channel defines a second resonator channel volume and the second resonator channel volume is smaller than the second resonator volume. In this way, it is particularly possible to minimize the influence of the resonator channels on the properties of the resonator elements.

[0020] In principle, it is possible to design the first or second resonator cavity in any shape. These resonator cavities can be easily formed in the form of a hollow cylinder, a hollow cuboid, or a hollow sphere.

[0021] It is advantageous if the at least one first injection element defines a first longitudinal axis of the injection element and / or if the at least one second injection element defines a second longitudinal axis of the injection element. Fuels and / or oxidants can be injected into the combustion chamber easily and in a defined manner, particularly by linear injection elements.

[0022] A simple construction of the injector device is made possible in particular by the fact that the first injection element longitudinal axis and / or the second injection element longitudinal axis run parallel to the longitudinal axis.

[0023] According to a further preferred embodiment of the invention, it can be provided that the at least one first resonator element defines a first resonator element longitudinal axis and / or that the at least one second resonator element defines a second resonator element longitudinal axis. Resonator elements configured in this way are excellently suited for easily calculating their damping properties.

[0024] It is advantageous if the first injection element longitudinal axis and the first resonator element longitudinal axis extend transversely, in particular perpendicularly, to one another, and / or if the second injection element longitudinal axis and the second resonator element longitudinal axis extend transversely, in particular perpendicularly, to one another. Such a configuration enables, in particular, a compact arrangement of the resonator elements relative to the injection elements, for example, in an injector plate.

[0025] Preferably, the at least one first injection element and the at least one second injection element are arranged or configured coaxially with one another. This makes it possible, in particular, to inject the fuel into the combustion chamber through an annular channel surrounding the oxidant injection element. Such coaxial injection of fuel and oxidant enables thorough mixing upon entry into the combustion chamber and thus high combustion efficiency.

[0026] It is advantageous if the at least one first flushing channel defines a first flushing channel longitudinal axis and / or if the at least one second flushing channel defines a second flushing channel longitudinal axis. Such flushing channels can thus be easily formed, for example, by drilling.

[0027] It is advantageous if the first flushing channel longitudinal axis and the longitudinal axis run parallel or substantially parallel to one another, and / or if the second flushing channel longitudinal axis and the longitudinal axis run parallel or substantially parallel to one another. Such a configuration enables a simple structure and thus simple manufacture of the injector device.

[0028] In order to minimize an influence of the scavenging channels on the resonator elements, it is advantageous if a first scavenging channel cross-sectional area defined by the at least one first scavenging channel is smaller than a first resonator channel cross-sectional area defined by the first resonator channel and / or if a second scavenging channel cross-sectional area defined by the at least one second scavenging channel is smaller than a second resonator channel cross-sectional area defined by the second resonator channel.

[0029] It is advantageous if the at least one first resonator element and / or the at least one second resonator element is designed in the form of a Helmholtz resonator or a λ / 4 resonator. Such resonator elements can be easily formed and tuned to the natural frequencies of the associated injection elements.

[0030] It is advantageous if the at least one first resonator element is assigned to at least one first injection element and / or if the at least one second resonator element is assigned to at least one second injection element. This configuration makes it possible, in particular, to assign a resonator element not only to one, but also to two, three, or more injection elements. This simplifies the design of the injector device, since, for example, only a single resonator element is required to assign it to two or more injection elements.

[0031] To enable an optimized reaction of fuel and oxidant in the combustion chamber, it is advantageous if the injector device comprises a plurality of first injection elements and / or a plurality of second injection elements. In particular, the number of first injection elements can correspond to the number of second injection elements.

[0032] It is advantageous if the first resonator elements assigned to the plurality of first injection elements are tuned to different natural frequencies of the plurality of first injection elements and / or if the second resonator elements assigned to the plurality of second injection elements are tuned to different natural frequencies of the plurality of second injection elements. This makes it possible, in particular, to specifically damp injection elements. For example, the resonator elements can be tuned to certain natural frequencies of the injection elements, which preferably couple to longitudinal modes of the combustion chamber. Others can be tuned to natural frequencies that couple to transverse or radial modes of the combustion chamber. In this way, the development of very strong injector-coupled pressure fluctuations in the combustion chamber can be effectively prevented.By damping the respective injection elements, flame oscillations in the combustion chamber with the acoustic natural frequencies of the injection elements are prevented. Where no fluctuations in heat release occur, they cannot couple with combustion chamber modes and thus lead to high-frequency, thermoacoustic combustion instabilities in the combustion chamber, which are caused by the injector coupling.

[0033] It is advantageous if the first resonator elements have different shapes and / or different first resonator volumes, and / or if the second resonator elements have different shapes and / or different second resonator volumes. Such a configuration makes it particularly easy to damp different natural frequencies of the injection elements to which the resonator elements are assigned. Of course, it is also fundamentally possible to design all first and / or second resonator elements identically.

[0034] According to a further preferred embodiment of the invention, it can be provided that the at least one first resonator element is arranged or formed in the region of an inlet of the at least one first injection element pointing in the direction of the first collection chamber and / or if the at least one second resonator element is arranged or formed in the region of an inlet of the at least one second injection element pointing in the direction of the second collection chamber. Such an arrangement of the resonator elements enables, in particular, a particularly compact design of the injector device. In particular, the length of optionally provided flushing channels can thus be easily minimized.

[0035] It is advantageous if the injector device comprises a first injector plate and a second injector plate, if the at least one first resonator element is arranged or formed in the first injector plate, and / or if the at least one second resonator element is arranged or formed in the second injector plate. Such an arrangement of the resonator elements makes it possible, in particular, to replace the injector plates in known engine devices and thus to easily retrofit the injector device with the resonator elements.

[0036] A simple design of the injector device can be achieved, in particular, by arranging or forming the first injector plate and the second injector plate parallel to one another. In particular, they can be arranged or formed transversely to the longitudinal axis.

[0037] A particularly compact design of the injector device can be achieved in particular by arranging or forming the second collecting space between the first injector plate and the second injector plate.

[0038] It is advantageous if the first injector plate is designed in the form of a throttle plate, and if the at least one first injection element is assigned a first throttle element in the region of its inlet, which defines a smaller flow cross-section than the at least one first injection element, and if the first throttle element is arranged or formed in or on the throttle plate. This enables, in particular, a compact design of the injector device. For example, it can be formed using a generative manufacturing process.

[0039] The manufacture of the injector device can be simplified in particular by the fact that the at least one first injection element is designed in the form of a bore in the throttle plate.

[0040] Advantageously, the at least one first injection element is arranged on a plate-shaped injector element holder or is designed in the form of an injector sleeve. Such first injection elements can be manufactured easily.

[0041] A compact design of the injector device can be achieved in particular in that the injector element holder, on the one hand, lies flat against the first injector plate and, on the other hand, delimits the second collecting space.

[0042] Advantageously, the at least one second injection element is arranged or formed on or in an injection head. The injection head can, in particular, form a boundary of the combustion chamber, thus enabling a compact design of an engine device.

[0043] Advantageously, the injection head forms an end wall that defines the combustion chamber and is arranged or formed opposite a nozzle of the combustion chamber. The nozzle of the combustion chamber serves as an outlet for the reaction products, thereby determining the thrust of the engine device.

[0044] The at least one second injection element can be formed in a simple manner if it is designed in the form of a bore in the injection head.

[0045] A second throttle element can be formed in particular in a simple manner in that the at least one second injection element tapers in a single stage in cross section to form the second throttle element.

[0046] The object stated at the outset is further achieved according to the invention in an engine device of the type described at the outset in that the injector device is designed in the form of one of the injector devices described above.

[0047] Equipping an engine device with such an injector device has, in particular, the advantages described above in connection with preferred embodiments of injector devices.

[0048] Preferably, the propulsion device is designed in the form of a rocket engine. Such a rocket engine can be used, in particular, to propel a rocket.

[0049] It is advantageous if the combustion chamber comprises an end wall opposite the nozzle, and if at least part of the injector device is arranged or formed in the end wall. Such an engine device can be designed to be particularly compact.

[0050] Conveniently, the engine device comprises at least one plenum, which is delimited by a plenum end wall. For example, the engine device can each have a separate plenum for the fuel and the oxidizer. The plenum end wall can, in particular, be arranged or configured to extend transversely to a longitudinal axis defined by the engine device. For example, a plenum end wall can be formed by the end wall opposite the nozzle and can delimit a plenum for the fuel. A second plenum end wall of the plenum for the fuel can, for example, be formed by the injector element holder described above.

[0051] The object set out at the outset is further achieved according to the invention in an aircraft and / or spacecraft of the type described at the outset in that the engine device is designed in the form of one of the engine devices described above.

[0052] Providing such an engine device has the particular advantage that the aircraft and / or spacecraft also has the advantages resulting from the special design of the engine device.

[0053] Preferably, the fuel tank is designed to hold liquid hydrogen or liquid methane. This allows, for example, the aircraft and / or spacecraft to be powered by a fuel mixture formed either by a combination of liquid hydrogen and liquid oxygen or by a combination of liquid methane and liquid oxygen.

[0054] Furthermore, it is advantageous if the aircraft and / or spacecraft comprises an oxidizer tank for accommodating a fluidic oxidizer. In particular, the fluidic oxidizer can be a liquid oxidizer, for example, liquid oxygen. Providing an oxidizer tank makes it possible, in particular, to operate the aircraft and / or spacecraft in space, where no oxygen-containing atmosphere is available from which gaseous oxygen can be extracted as an oxidizer.

[0055] The object stated at the outset is further achieved according to the invention in a method of the type described at the outset in that the at least one first resonator element and the first collecting chamber are fluidically connected to one another via a first flushing channel and / or that the at least one second resonator element and the second collecting chamber are fluidically connected to one another via a second flushing channel and that the fluid flowing through the injection elements is also allowed to flow at a low flow velocity through the respective resonator element, whereby it can be ensured that the same conditions prevail in the respective resonator at all times as in the injection element to be damped.

[0056] Proceeding in the manner described has the particular advantage of effectively preventing the development of very strong injector-coupled pressure fluctuations in the combustion chamber. Damping the respective injection elements prevents flame oscillations in the combustion chamber that are associated with the acoustic eigenfrequencies of the injection elements. Where no fluctuations in heat release occur, they cannot couple with combustion chamber modes and thus lead to high-frequency, thermoacoustic combustion instabilities in the combustion chamber caused by the injector coupling.

[0057] The following description of preferred embodiments of the invention serves to explain it in more detail in conjunction with the drawings. They show: Figure 1: a schematic longitudinal sectional view of an embodiment of an engine device; Figure 2: an enlarged detail view of the engine device from Figure 1; Figure 3: a schematic perspective exploded view of the engine device from Figure 1 ; Figure 4: a sectional view along line 4-4 in Figure 3 ; Figure 5: a sectional view along line 5-5 in Figure 3 ; Figure 6: a schematic longitudinal sectional view of part of an embodiment of an injector device; Figure 7: a schematic, partially exploded view of an engine device with the throttle plate removed; Figure 8: a plan view of the throttle plate from Figure 7 ; Figure 9: a sectional view along line 9-9 in Figure 8 ; Figure 10: an enlarged detail view of area A from Figure 9 ; Figure 11: a sectional view along line 11-11 in Figure 9 ; Figure 12: an enlarged detail view of area B from Figure 11 ; Figure 13: a schematic representation of a plan view similar Figure 8to a further embodiment of a throttle plate; Figure 14: a view of the embodiment of the throttle plate from Figure 13 from below; Figure 15: a representation of the dependence of a maximum pressure on the frequency for a first injection element for the oxidant (solid curve) and for an associated resonator element in the form of a Helmholtz resonator (dashed curve), which is tuned to the second longitudinal natural frequency of the injection element; Figure 16: a schematic representation of an embodiment of a spacecraft; and Figure 17: a schematic representation of an embodiment of an aircraft.

[0058] In Figure 1 A first embodiment of an engine device 10 is schematically shown.

[0059] The engine device 10 comprises a combustion chamber 12 which is delimited by a combustion chamber wall 14.

[0060] The engine device 10 is essentially rotationally symmetrical with respect to a longitudinal axis 16.

[0061] The combustion chamber 12 is essentially hollow-cylindrical and tapers to a constriction 18, from which an outlet 20 with a widening cross-section is formed. The constriction 18 defines a convergent nozzle 22 with a sound passage in the narrowest cross-section defined by the constriction 18.

[0062] Arranged opposite the outlet 20 is an end wall 24 delimiting the combustion chamber 12. Arranged parallel to the end wall 24 and spaced therefrom is a second partition wall 26, which, on a side facing away from the combustion chamber 12, delimits a first collection chamber 28 for receiving a fluidic oxidant 100. The second end wall 26 has a side surface facing the combustion chamber 12, which delimits a second collection chamber 30 for receiving a fluidic fuel 102. The second collection chamber 30 is also delimited by the end wall 24, specifically with a side surface thereof facing away from the combustion chamber 12.

[0063] For introducing the fluidic fuel and the fluidic oxidizer into the combustion chamber 12, the engine device 10 comprises an injector device 32.

[0064] The injector device 32 defines an injector device longitudinal axis that coincides with the longitudinal axis 16. Furthermore, the injector device 32 comprises a plurality of first injection elements 34 and a plurality of second injection elements 36. The first injection elements 34 are configured in the form of a first fluid channel 38 for fluidly connecting the first collection chamber 28 and the combustion chamber 12. The second injection elements 36 are configured in the form of second fluid channels 40 for fluidly connecting the second collection chamber 30 and the combustion chamber 12.

[0065] The first injection elements 34 define first injection element longitudinal axes 42. The second injection elements 36 define second injection element longitudinal axes 44.

[0066] The first injection elements 34 are arranged on a plate-shaped injector element holder and are designed in the form of an injector sleeve 48. The injector element holder 46 defines the second collection chamber 30 and rests flatly against an injector plate 50 with a second side surface.

[0067] The injector element holder 46 and the injector plate 50 together form the partition wall 26, which separates the collecting spaces 28 and 30 from each other.

[0068] In a further embodiment, the injector element holder 46 and the injector plate 50 are formed as a single unit in one piece.

[0069] The end wall 24 forms an injection head 52. The second injection elements 36 are arranged and formed on or in the injection head 52.

[0070] The second injection elements 36 are formed as bores 54 in the end wall 24. Their longitudinal axes run parallel to the longitudinal axis 16.

[0071] One of the bores 54 is coaxial with the longitudinal axis 16. The other bores 54 are arranged on two circles 56 and 58 concentric with the longitudinal axis.

[0072] An inner diameter 60 of the bores 54 is slightly larger than an outer diameter 62 of the injector sleeve 48, so that an annular space 64 is formed which is delimited by the bore 54 on the one hand and the injector sleeve 48 on the other hand and which defines the second fluid channel 40 for the fluidic fuel 102.

[0073] A length of the injector sleeve 48 is selected such that a free end 66 thereof ends in the region of a free end 68 of the bores 54, which points towards the combustion chamber 12.

[0074] The injector plate 50 is provided with a number of bores 70 corresponding to the number of bores 54, the inner diameter 72 of which is slightly smaller than an inner diameter 74 of the injector sleeves 48. The bores 70 and 54 thus form a first fluid channel 38 which widens in a single stage in the transition region between the injector plate 50 and the injector holder 46.

[0075] The injector device 32 further comprises a plurality of first resonator elements 76 and a plurality of second resonator elements 78. The first resonator elements 76 are each assigned to a first injection element 34, and the second resonator elements 78 are each assigned to a second injection element 36.

[0076] The first resonator elements 76 are each tuned to a natural frequency of the associated first injection element 34. The second resonator elements 78 are each tuned to a natural frequency of the associated second injection element 36.

[0077] In the Figures 1 to 5 In the illustrated embodiment of the injector device 32, the first resonator elements 76 define first resonator element longitudinal axes 80 and the second resonator elements 78 define second resonator element longitudinal axes 82.

[0078] The first resonator element longitudinal axes 80 together span a plane extending transversely to the longitudinal axis 16, which plane runs parallel to a plane defined by the second resonator element longitudinal axes 82.

[0079] The first injection element longitudinal axes 42 and the first resonator element longitudinal axes 80 run transversely, namely perpendicularly, to one another. The second injection element longitudinal axes 44 and the respectively associated second resonator element longitudinal axes 82 also run transversely, namely perpendicularly, to one another.

[0080] The first resonator elements 76 are fluidly connected to the associated first injection element 34. Likewise, the second resonator elements 78 are fluidly connected to the associated second injection element 36.

[0081] The first resonator elements 76 each define a first resonator cavity 84, which defines a first resonator volume. The second resonator elements 78 each define a second resonator cavity 86.

[0082] In the Figures 1 to 5 In the schematically illustrated embodiment of the injector device 32, the first and second resonator elements 76 and 78 respectively open directly into the bore 70 and the bore 54, respectively.

[0083] The first resonator cavity 84 and the second resonator cavity 86 are in the Figures 1 to 5In the illustrated embodiment of the injector device 32, they are designed in the form of hollow cuboids 88 and 90, respectively. In principle, they can have any desired shape. In other embodiments, they are designed in the form of hollow cylinders or hollow spheres.

[0084] Furthermore, the first resonator elements 76 and the first collection chamber 28 are fluidly connected to one another via first flushing channels 92. Furthermore, the second resonator elements 78 and the second collection chamber 30 are each fluidly connected to one another via a second flushing channel 94.

[0085] The first flushing channel 92 defines a first flushing channel longitudinal axis 96. The second flushing channel 94 defines a second flushing channel longitudinal axis 98.

[0086] The first flushing channel longitudinal axis 96 and the longitudinal axis 16 run parallel or substantially parallel to each other. The second flushing channel longitudinal axis 98 and the longitudinal axis 16 also run parallel or substantially parallel to each other.

[0087] In the Figures 1 to 5 In the illustrated embodiment of the injector device 32, the first resonator elements 76 are each assigned to a first injection element 34. The second resonator elements 78 are each assigned to a second injection element 36.

[0088] Overall, the described embodiment of the injector device 32 comprises nineteen first and second injection elements 34, 36, thus a plurality of first and second injection elements 34, 36.

[0089] As shown schematically in Figure 2As shown, the fluidic oxidant 100 flows from the first collection chamber 28 through the bore 70 forming a throttle into the injector sleeve 48, exits at the end 66 thereof, and flows into the combustion chamber 12. The fluidic fuel 102 flows from the second collection chamber 30 through the annular spaces 64 into the combustion chamber 12 and mixes with the fluidic oxidant 100 upon exiting the second injection elements 36.

[0090] The fluidic oxidant 100 can also flow through the first purge channels 92 into the first resonator elements 76. As a result, the conditions prevailing in the first injection element 34 and the first resonator element 76 are identical.

[0091] The fluidic fuel 102 flows through the second purge channels 94 into the second resonator elements 78, so that here too the conditions in the fluidic fuel 102 are identical both in the second resonator element 78 and in the second injection element 36.

[0092] As already described above, the respective resonator elements 76, 78 can be tuned to natural frequencies of the injection elements 34, 36 independently of the operating conditions of the engine device 10.

[0093] The Figures 6 to 12 show schematically a further embodiment of an engine device 10. Identical elements and components of the Figures 6 to 12 The parts of the illustrated embodiment of the engine device 10 are provided with the same reference numerals used to designate elements and components of the Figures 1 to 5 schematically illustrated engine device 10.

[0094] Figure 6shows schematically a longitudinal sectional view of the engine device 10 in the area of ​​the injector device 32. The Figure 6 The embodiment of the injector device 32 shown differs from the injector device 32 of the Figures 1 to 5 illustrated embodiment in particular in that the first resonator elements 76 do not open directly into the associated bore 70, but are fluidly connected to it via a first resonator channel 104.

[0095] Furthermore, the second injection element 36 is again formed by the bore 54 in the injection head 52, wherein the bore 54, starting from the second collecting chamber 30, tapers in one step in the inner diameter after approximately two-thirds of its length, whereby a throttle is formed in the end wall 24.

[0096] In the Figures 6 to 12In the illustrated embodiment of the injector device 32, no second resonator elements 78 are provided. In a further, not illustrated embodiment of the engine device 10, which is otherwise identical to the engine device 10 according to Figures 6 to 12 formed, second resonator channels 106 are provided, which fluidically connect the second resonator elements 78 and the associated second injection elements 36. In Figure 6 For illustration purposes, an optional second resonator element 78 is shown in dashed lines, which is fluidically connected to the second injection element 36 via the associated second resonator channel 106, also shown in dashed lines. The second resonator element 78 can, as in Figure 6 shown in dashed lines, furthermore be fluidly connected to the second collecting chamber 30 via the optional flushing channel 94.

[0097] The first resonator channel 104 defines a first resonator channel volume that is smaller than the first resonator volume. Furthermore, the second resonator channel 106 defines a second resonator channel volume that is smaller than the second resonator volume.

[0098] Furthermore, in one embodiment of the engine device 10, the first purge channel 92 defines a first purge channel cross-sectional area that is smaller than a first resonator channel cross-sectional area defined by the first resonator channel 104.

[0099] In one embodiment of the engine device 10, a second purge channel cross-sectional area defined by the second purge channel 94 is smaller than a second resonator channel cross-sectional area defined by the second resonator channel 106.

[0100] The first resonator elements 76 and the second resonator elements 78 of the described embodiments of engine devices 10 are designed in the form of Helmholtz resonators.

[0101] In other embodiments of engine devices 10, they are designed in the form of λ / 4 resonators.

[0102] In further embodiments of engine devices 10, the first and second resonator elements 76, 78 may be designed partly in the form of Helmholtz resonators and partly in the form of λ / 4 resonators.

[0103] In one embodiment of an injector device 32, the first resonator elements 76 have different shapes. Figures 6 to 12 In the illustrated embodiment, a total of 42 first injection elements 34 are formed, of which 24 are arranged on an outer circle 59, 12 on a middle circle 58 and six on an inner circle 56. In Figure 12the first resonator elements 76a, 76b, 76c, 76d and 76e are formed in the injector plate 50, which can also be referred to as a throttle plate, wherein a first resonator element 76a or 76b is assigned to the first injection elements 34 of the circuit 59, a first resonator element 76c or 76d is assigned to each first injection element 34 of the second circuit 58, and a first resonator element 76e is assigned to each first injection element 34 of the third circuit 56.

[0104] The resonator elements 76a, 76b, 76c, 76d and 76e therefore have different shapes and different first resonator volumes.

[0105] Due to the different design of the first resonator elements 76a, 76b, 76c, 76d and 76e, they are tuned to different natural frequencies of the respective first injection elements 34 assigned to them. Figures 6 to 12In the illustrated embodiment of the injector device 32, the first resonator elements 76a and 76b are tuned to a second eigenmode (2L) of the first injection elements 34, which couples to a first tangential mode of the combustion chamber 12 at approximately 10 kHz.

[0106] The first resonator elements 76c and 76d, on the other hand, are tuned to the third eigenmode (3L) of the first injection elements 34, which couples to a second tangential mode of the combustion chamber 12 at about 15 kHz.

[0107] The first resonator elements 76e are tuned to the fourth eigenmode (4L) of the first injection elements 34, which couples to a first radial mode of the combustion chamber 12 at about 20 kHz.

[0108] The first resonator elements 76a, 76b, 76c, 76d and 76e are each fluidly connected to the first collecting chamber 28 via flushing channels 92a, 92b and 92c.

[0109] The injector plate 50 is screwed to the injector element holder 46 with screws 108. Blind holes 112 provided with an internal thread 110 are formed in the injector element holder 46. The internal threads 110 correspond to external threads 114 of the screws 108.

[0110] In the injector plate 50, holes 124 with recesses are also formed, through which the part of the screws 108 provided with the external thread 114 passes.

[0111] The blind holes 112 are arranged in a ring shape on a circle 116 which is formed between the circles 58 and 59 concentrically to the longitudinal axis 16.

[0112] The first resonator elements 76a and 76b, which are fluidly connected to the first injection elements 34 of the outermost circle 59, differ in their shape but not in their tuning to the specific natural frequency of the first injection element 34 of the outermost circle 59.

[0113] The first resonator elements 76c and 76d also differ slightly in shape. However, they are also each tuned to the same natural frequency of the first injection element 34 of the middle circuit 58.

[0114] The different design of the first resonator elements 76a and 76b or 76c and 76d is based on the limited spatial situation, which does not allow to provide only three different first resonator elements 76.

[0115] The first resonator elements 76 are each arranged or formed in the region of an inlet 118 of the first injection element 34 pointing in the direction of the first collecting chamber 28.

[0116] The second resonator elements 78 are arranged or formed in the region of an inlet 120 of the second injection element 36 pointing in the direction of the second collecting chamber 30.

[0117] In the described embodiments of injector devices 32, the first resonator elements 76 are arranged or formed in the injector plate 50. The second resonator elements 78 are arranged or formed in the end wall 24, which forms a second injector plate 122. The injector plates 50 and 122 are arranged or formed parallel to one another and extend transversely, namely perpendicularly, to the longitudinal axis 16.

[0118] The injector plate 50 is designed in the form of a throttle plate. As described, the bore 70 in the region of the inlet 118 of the first injection element 34 forms a first throttle element, which defines a smaller flow cross-section than the remaining part of the first injection element 34.

[0119] Another embodiment of an injector plate 50 is shown schematically in the Figures 13 and 14 shown.

[0120] In the embodiment of the injector plate 50 of the Figures 13 and 14Two first resonator elements 76a and 76b are schematically shown. The resonator element 76a is fluidly connected to a total of three first injection elements 34 via three first resonator channels 104. Furthermore, the first resonator element 76a is fluidly connected to the first collection chamber 28 via a flushing channel 92.

[0121] The Figure 14 The schematically illustrated first resonator element 76b is fluidly connected to two first injection elements 34 via two first resonator channels 104.

[0122] In principle, first and second resonator elements 76 and 78 can be assigned to only one injection element 34 in some embodiments. In other embodiments of injector devices 32, first resonator elements 76 and second resonator elements 78 can also be assigned to two, three, or more first and second injection channels 34, 36, respectively. In this way, very compact injector plates 50 can be formed.

[0123] In Figure 15 The maximum pressure in the first injection element 34 and in the associated first resonator element 76 is schematically shown at the respective natural frequencies of the overall geometry of the injection elements 34. This pressure distribution clearly shows that a pressure peak is reached at the second eigenmode of the first injection element 34 and, at the same time, a broad frequency range of the first injection element 34 is damped.

[0124] The partition wall 26 of the engine device 10 is subjected to less thermal stress than the combustion chamber wall 14. This makes it possible to form the injector plate 50 from stainless steel or nickel-based alloys.

[0125] In one embodiment, the injector plate 50 is formed using an additive manufacturing process. In particular, selective laser melting can be used here. This enables highly complex structures of the injector plate, particularly for forming the first resonator elements 76.

[0126] In Figure 16 An exemplary embodiment of a spacecraft 126 is schematically depicted. It comprises one of the above-described engine devices 10 as well as a fuel tank 128 for accommodating a fluidic, in particular liquid, fuel 102 and an oxidizer tank 130 for accommodating a fluidic, in particular liquid, oxidizer 100. The oxidizer 100 can in particular be liquid oxygen.

[0127] The fuel tank 128 is designed to hold a fluid fuel, for example a liquid fuel in the form of hydrogen or methane.

[0128] The oxidizer tank 130 is fluidly connected to the first plenum 28 via a fluid line 132. The fuel tank 128 is connected to the second plenum 30 via another fluid line 134.

[0129] Figure 17 schematically shows an embodiment of an aircraft 136. It comprises a fuel tank 128 and an engine device 10, which is fluidly connected to the fuel tank 128 via a fluid line 134.

[0130] An oxidizer tank is not necessarily required for the aircraft 136 if the aircraft 136 moves in regions of the atmosphere in which sufficient atmospheric oxygen is available to serve as an oxidizer for the fuel 102 carried by the aircraft 136 in the fuel tank 128. List of reference symbols

[0131] 10Engine device 12Combustion chamber 14Combustion chamber wall 16Longitudinal axis 18Constriction 20Outlet 22Nozzle 24End wall 26Partition wall 28First plenum 30Second plenum 32Injector device 34First injection element 36Second injection element 38First fluid channel 40Second fluid channel 42First injection element longitudinal axis 44Second injection element longitudinal axis 46Injection element holder 48Injector sleeve 50Injector plate 52Injection head 54Bore 56Circle 58Circle 59Circle 60Inner diameter 62Outer diameter 64Annular space 66End 68End 70Bore 72Inner diameter 74Inner diameter 76, 76a, 76b, 76c, 76d, 76e first resonator element 78 second resonator element 80 first resonator element longitudinal axis 82 second resonator element longitudinal axis 84 first resonator cavity 86 second resonator cavity 88 cuboid 90 cuboid 92, 92a, 92b, 92c first purge channel 94 second purge channel 96 first purge channel longitudinal axis 98 second purge channel longitudinal axis 100 oxidizer 102 fuel 104, 104a, 104b, 104c, 104d,104First resonator channel 106Second resonator channel 108Screws 110Internal thread 112Blind hole 114External thread 116Circle 118Inlet 120Inlet 122Second injector plate 124Bore 126Spacecraft 128Fuel tank 130Oxidizer tank 132Fluid line 134Fluid line 136Aircraft,

Claims

1. Injector device (32) for an engine device (10) for introducing a fluidic, in particular a liquid, fuel (102) and a fluidic, in particular liquid, oxidizing agent (100) into a combustion chamber (12) of the engine device (10), which injector device (32) defines a longitudinal axis (16) and comprises at least one first injection element (34), which is configured in the form of a first fluid channel (38) for fluidically connecting a first collection space (28) for the fluidic oxidizing agent (100) and the combustion chamber (12), and at least one second injection element (36), which is configured in the form of a second fluid channel (40) for fluidically connecting a second collection space (30) for the fluidic fuel (102) and the combustion chamber (12), wherein at least one first resonator element (76, 76a, 76b, 76c, 76d, 76e) is associated with the at least one first injection element (34) and / or wherein at least one second resonator element (78) is associated with the at least one second injection element (36), and wherein the at least one first resonator element (76, 76a, 76b, 76c, 76d, 76e) is adapted to an eigenfrequency of the associated at least one first injection element (34) and / or wherein the at least one second resonator element (78) is adapted to an eigenfrequency of the associated at least one second injection element (36), characterized in that the at least one first resonator element (76, 76a, 76b, 76c, 76d, 76e) and the first collection space (28) are fluidically connected to one another by way of a first flushing channel (92) and / or in that the at least one second resonator element (78) and the second collection space (30) are fluidically connected to one another by way of a second flushing channel (94), so that the fluid flowing through the injection elements (34, 36) also flows at a low flow speed through the respective resonator element (76, 76a, 76b, 76c, 76d, 76e; 78), thereby ensuring that the same conditions prevail in the respective resonator element (76, 76a, 76b, 76c, 76d, 76e; 78) at any one time as in the injection element (34, 36) to be dampened.

2. Injector device in accordance with Claim 1, characterized in that the at least one first resonator element (76, 76a, 76b, 76c, 76d, 76e) is fluidically connected to the at least one first injection element (34) and / or in that the at least one second resonator element (78) is fluidically connected to the at least one second injector element (36).

3. Injector device in accordance with any one of the preceding Claims, characterized in that the at least one first resonator element (76, 76a, 76b, 76c, 76d, 76e) comprises a first resonator cavity (84), which defines a first resonator volume, and in that a first resonator channel (104, 104a, 104b, 104c, 104d, 104e) fluidically connects the at least one first injection element (34) and the first resonator cavity (84) and / or in that the at least one second resonator element (78) comprises a second resonator cavity (86), which defines a second resonator volume, and in that a second resonator channel (106) fluidically connects the at least one second injection element (36) and the second resonator cavity (86), wherein, in particular, a) the first resonator channel (104, 104a, 104b, 104c, 104d, 104e) defines a first resonator channel volume and wherein the first resonator channel volume is smaller than the first resonator volume and / or wherein the second resonator channel (106) defines a second resonator channel volume and wherein the second resonator channel volume is smaller than the second resonator volume and / or b) the first resonator cavity (84) and / or the second resonator cavity (86) is configured in that form of a hollow cylinder, a hollow cuboid (88, 90), or a hollow sphere.

4. Injector device in accordance with any one of the preceding Claims, characterized in that a) the at least one first injection element (34) defines a first injection element longitudinal axis (42) and / or in that the at least one second injection element (36) defines a second injection element longitudinal axis (44), and / or b) the at least one first resonator element (76, 76a, 76b, 76c, 76d, 76e) defines a first resonator element longitudinal axis (80) and / or in that the at least one second resonator element (78) defines a second resonator element longitudinal axis (82), and / or c) the at least one first injection element (34) and the at least one second injection element (36) are arranged or formed coaxially to one another and / or d) the at least one first flushing channel (92) defines a first flushing channel axis (96) and / or in that the at least on second flushing channel (94) defines a second flushing channel axis (98).

5. Injector device in accordance with any one of the preceding Claims, characterized in that a first flushing channel cross-sectional area defined by the at least one first flushing channel (92) is smaller than a first resonator channel cross-sectional area defined by the first resonator channel (104, 104a, 104b, 104c, 104d, 104e) and / or in that a second flushing channel cross-sectional area defined by the at least one second flushing channel (92) is smaller than a second resonator channel cross-sectional area defined by the second resonator channel (106).

6. Injector device in accordance with any one of the preceding Claims, characterized in that a) the at least one first resonator element (76, 76a, 76b, 76c, 76d, 76e) and / or in that the at least one second resonator element (78) is configured in the form of a Helmholtz resonator or in the form of a λ / 4 resonator and / or b) the at least one first resonator element (76, 76a, 76b, 76c, 76d, 76e) is associated with at least one first injection element (34) and / or in that the at least one second resonator element (78) is associated with at least one second injection element (36).

7. Injection device in accordance with any one of the preceding Claims, characterized in that the injector device (32) comprises a plurality of first injection elements (34) and / or a plurality of second injection elements (36).

8. Injector device in accordance with any one of the preceding Claims, characterized in that the at least one first resonator element (76, 76a, 76b, 76c, 76d, 76e) is arranged or formed in the region of an inlet (118) of the at least one first injection element (34) facing in the direction toward the first collection space (28) and / or in that the at least one second resonator element (78) is arranged or formed in the region of an inlet (120) of the at least one second injection element (36) facing in the direction toward the second collection space (30).

9. Injector device in accordance with any one of the preceding Claims, characterized in that the injector device (32) comprises a first injector plate (50) and a second injector plate (26), in that the at least one first resonator elements (76, 76a, 76b, 76c, 76d, 76e) are arranged or formed in the first injector plate (50) and / or in that the at least one second resonator elements (78) are arranged or formed in the second injector plate (122).

10. Injector device in accordance with any one of the preceding Claims, characterized in that the at least one first injection element (34) is arranged on a plate-shaped injector element holder (46) and is configured in the form of an injector sleeve (48).

11. Injector device in accordance with any one of the preceding Claims, characterized in that the at least one second injection element (36) is arranged or formed on or in an injection head (52).

12. Injector device in accordance with any one of the preceding Claims, characterized in that that the at least one second injection element (36) tapers in cross section in a single stage to form a second throttle element.

13. Engine device (10), in particular for an aircraft (136) and / or a spacecraft (126), which engine device (10) comprises a combustion chamber (12) with a nozzle (22) and comprises an injector device (32) arranged opposite the nozzle (22), characterized in that the injector device (32) is configured in accordance with any one of the preceding Claims.

14. Aircraft and / or spacecraft (136, 126) with an engine device (10) and a fuel tank (128) for accommodating a fluidic, in particular liquid, fuel (102), characterized in that the engine device (10) is configured in the form of an engine device (10) in accordance with Claim 13.

15. Method for operating an engine device (10), in which method a fluidic, in particular liquid, fuel (102) and a fluidic, in particular liquid, oxidizing agent (100) is introduced with an injector device (32) into a combustion chamber (12) of the engine device (10), which injector device (32) comprises at least one first injection element (34) for fluidically connecting a first collection space (28) for the fluidic oxidizing agent (100) and the combustion chamber (12), and at least one second injection element (36) for fluidically connecting a second collection space (30) for the fluidic fuel (102) and the combustion chamber (12), wherein acoustic natural vibrations in the at least one first injection element (34) and / or wherein acoustic natural vibrations in the at least one second injection element (36) are dampened, wherein at least one first resonator element (76, 76a, 76b, 76c, 76d, 76e) is associated with the at least one first injection element (34) and / or wherein at least one second resonator element (78) is associated with the at least one second injection element (36), and wherein the at least one first resonator element (76, 76a, 76b, 76c, 76d, 76e) is adapted to an eigenfrequency of the associated at least one first injection element (34) and / or wherein the at least one second resonator element (78) is adapted to an eigenfrequency of the associated at least one second injection element (36), characterized in that the at least one first resonator element (76, 76a, 76b, 76c, 76d, 76e) and the first collection space (28) are fluidically connected to one another by way of a first flushing channel (92) and / or in that the at least one second resonator element (78) and the second collection space (30) are fluidically connected to one another by way of a second flushing channel (94), and in that the fluid flowing through the injection elements (34, 36) also is let flown at a low flow speed through the respective resonator element (76, 76a, 76b, 76c, 76d, 76e), thereby ensuring that the same conditions prevail in the respective resonator element (76, 76a, 76b, 76c, 76d, 76e) at any one time as in the injection element (34, 36) to be dampened.