WO2009150069A2

WO2009150069A2 - Combustion chamber device, and method for the operation of a combustion chamber device

Info

Publication number: WO2009150069A2
Application number: PCT/EP2009/056647
Authority: WO
Inventors: Johannes Lux; Oskar Haidn; Dmitry Suslov
Original assignee: Deutsches Zentrum für Luft- und Raumfahrt e.V.
Priority date: 2008-06-09
Filing date: 2009-05-29
Publication date: 2009-12-17
Also published as: DE102008028208B4; DE102008028208A1; DE202009018138U1; WO2009150069A3

Abstract

Disclosed is a combustion chamber device comprising at least one combustion chamber, at least one injection head that has at least one injector for feeding fuel and oxidant to a combustion chamber, and a laser apparatus for generating at least one laser beam for igniting a fuel-oxidant mixture. In order to design a combustion chamber device that allows for a reliable ignition process in order to ignite a flame, the at least one injector encompasses at least one internal injector element, an external injector element, and a common fluid duct for fluids conducted within the internal injector element and the external injector element. Said common fluid duct leads into the combustion chamber, and the at least one igniting laser beam is injected into the injector in the common fluid duct.

Description

Combustion chamber apparatus and method of operating a combustor

The invention relates to a combustion chamber device comprising at least one combustion chamber, at least one injection head with at least one injector for supplying fuel and oxidizer to a combustion chamber and a laser device for generating at least one laser beam for igniting a fuel-oxidizer mixture.

Furthermore, the invention relates to an engine, which comprises at least one combustion chamber device.

The invention further relates to a method of operating a combustion chamber device in which a fuel-oxidizer mixture is ignited.

In the known combustor devices and engines, for example, in the article by Huzel, D.K. and Huang, D.H., Modern Engineering for Design of Liquid-Propellant Rocket Engines. AIAA, Progress in Astronautics and Aeronautics, Vol. 147, 1992, disclosed a pyrotechnic igniter for igniting a flame in the combustor and / or engine. Such pyrotechnic igniters have the disadvantage that they can only be used once.

DE 10 2007 033 809 A1 discloses a laser ignition system for an internal combustion engine.

DE 37 31 046 A1 discloses a method for initiating an exothermic chemical reaction in which a catalyst bed is exposed to a laser beam. DE 15 38 106 A discloses a magneto-hydrodynamic generator.

DE 603 07 033 T2 discloses a pulse combustion device which is used for example in a turbine engine.

EP 0 816 674 A1 discloses a combustion chamber in which an atomized fuel is burned with compressed air. The fuel-air mixture is for this purpose ignited by means of a laser beam, which is directed to a region downstream of a fuel nozzle in a combustion chamber of the combustion chamber.

WO 2007/011361 A2 discloses a device for generating a spark and a diagnostic device by means of which the spark and / or a flame can be examined.

WO 98/11388 A1 discloses a laser ignition system for igniting a fuel-air mixture in a combustion chamber, wherein the laser beam is directed into a combustion chamber of the combustion chamber downstream of a fuel nozzle.

US 5,857,323 A discloses a rocket engine which is throttable over a large thrust range due to a porous primary fuel injector.

US 5,845,480 discloses a combustion chamber in which a fuel-air mixture can be ignited by irradiation of an ignition region with microwave and laser radiation.

US 5,673,550 discloses a method and apparatus for igniting an air-fuel spray by means of a laser device. US 4,302,933 discloses a jet engine in which a fuel-air mixture is ignited behind a flame holder by means of a laser beam.

The invention is based on the object to provide a combustion chamber device of the type mentioned, which allows a reliable ignition for igniting a flame.

This object is achieved according to the invention in that the at least one injector comprises at least one inner injector element and one outer injector element, and comprises a common fluid channel for fluids guided in the inner injector element and in the outer injector element, wherein the common fluid channel opens into the combustion chamber and the at least one laser beam is blasted into the injector in the common fluid channel.

By directing a laser beam on the fuel-oxidizer mixture in the injector in the common fluid channel for igniting the fuel-oxidizer mixture ignition is particularly reliable feasible. A laser beam can be repeatedly directed to the fuel-Oxidator- mixture, so that an ignition process with little effort at short intervals is repeatable.

In the combustion chamber device according to the invention, ignition of the fuel-oxidizer mixture takes place not far from the injectors, but rather directly into the injectors in the region of the first contact of the reactants (for example hydrogen and oxygen). This allows a "gentle" ignition of the fuel-oxidizer mixture, wherein a pressure peak, which arises when large quantities of a combustible fuel-oxidizer mixture accumulate and ignite in a combustion chamber, and which can lead to the destruction of the combustion chamber device, is prevented. Furthermore, the combustion chamber device according to the invention can offer the advantage that due to the ignition in a very small area at the location of the first contact of the reactants, the laser beam can be focused very accurately and thus a very high energy density can be achieved at low laser power.

In one embodiment of the combustion chamber device according to the invention, it can further be ensured that the laser beam is guided only through the region with a reactant (for example through the region in which hydrogen is passed). Due to the at least approximately homogeneous optical properties of this range, a nearly constant optical refractive index results with correspondingly minimal scattering and good focusing of the laser beam. In this way, the required ignition energy can be brought to the ignition site with minimal losses. In particular, it is prevented that at least part of the laser beam is scattered and / or reflected in a passage through a two- or multi-component region.

It can be advantageous if the laser device serving as the ignition source is integrated in an injector. As a result, the combustion chamber device can be designed to save space.

Advantageously, at least two mutually different fluids can be guided separately by means of the injector.

It may be particularly advantageous if the at least one injector comprises at least one injector element designed as a fuel injector element for supplying fuel and at least one injector element designed as an oxidizer injector element for supplying oxidant. In this way, both fuel and oxidizer can be supplied by means of the injector. It may be favorable if the inner injector element and the outer injector element of the at least one injector are arranged coaxially with one another. In particular, it may be provided that the fluids guided into the injector elements are guided coaxially with one another without a swirl generation and without atomization. By such a coaxial irradiation is preferably obtained an ignitable fuel-oxidizer mixture, especially when using hydrogen and oxygen as a fuel or oxidizer.

In principle, it can be provided that the at least one injector comprises at least two inner injector elements.

It can be particularly favorable when at least three injector elements of the at least one injector are arranged in a tricoaxial manner. As a result, at least three fluids, for example different from one another, can be guided separately by means of the injector.

It can be advantageous if the at least one injector comprises at least one injector tube.

In one embodiment of the invention, it can be provided that an inner and / or an outer chamfer is provided at a rear end of at least one injector element in the inflow direction. In this way, mixture formation in the inflow direction behind the injector element is favored.

It may be advantageous if the at least one injector opens at an injector opening directly into the combustion chamber.

The inner injector element preferably opens into the common fluid channel. It can advantageously be provided that at least one orifice opening of the inner injector element is arranged offset from the direction of entry of a recession plane of the at least one injector against an inflow direction. As a result, an optimized flow within the combustion chamber device is possible.

In particular, by suitable choice of the relative distances and the diameters of the mouth openings and the exit plane, a flame-anchoring zone can be formed within the injector and a flame can be kept more stable there.

Furthermore, such a retraction of the orifice of the at least one injector element relative to the exit plane of the at least one injector offers the advantage that an opening angle of a flame forming on entry into the combustion chamber increases. As a result, this leads to improved performance data of the combustion chamber, in particular to a better combustion stability and a higher combustion efficiency.

It can be advantageous if the laser device comprises at least one laser diode. In this way, a laser beam is easily generated.

Alternatively or additionally, other laser devices such as solid-state lasers, gas lasers, dye lasers, etc. may be used.

To supply the laser device with energy, a portable power supply, for example a battery, is preferably provided.

In one embodiment of the invention it is provided that the laser device has such a laser wavelength that the fuel-oxidizer mixture, in particular the oxidizer, is photochemically excited by means of the laser device. It can be provided that a laser beam is tuned to the oxidizer with regard to an absorption wavelength, the activation energy or the emissivity for a primary excitation.

Advantageously, it can be provided that the laser beam with a frequency of at least 10 Hz, in particular with a frequency of several 100 Hz, pulsates to increase the ignition safety.

It can be advantageous if the laser device comprises at least one light guide for guiding the at least one laser beam.

It may be favorable if the laser device comprises at least one optical system for focusing the at least one laser beam.

It may be particularly advantageous if at least one optical access is provided in an outer wall of the at least one injector. As a result, a laser beam can be easily directed into an interior of the injector.

Furthermore, it can advantageously be provided that the at least one optical access is arranged in a direction parallel to the inflow direction between at least one orifice opening of an injector element, in particular of the inner injector element, and an exit plane of the at least one injector. As a result, the at least one laser beam can be easily directed to a fuel-oxidizer mixture that already forms within the injector.

In one embodiment of the invention, it may be provided that the combustion chamber device comprises at least one detection device. In this way, a simple monitoring of the combustion chamber device can take place. It may be favorable if the at least one detection device comprises at least one light detector. In this way, light emitted from the flame in the combustion chamber device can be easily detected.

It can be particularly favorable if the at least one detection device comprises at least one light guide. In this way, light emitted from the flame in the combustion chamber device can easily be guided to the detection device.

It can be advantageous if the at least one detection device is arranged on at least one injector such that a flame can be detected in the region in which ignition of the fuel-oxidizer mixture takes place by means of at least one laser beam. In this way it is particularly easy to monitor whether ignition of the fuel-oxidizer mixture has taken place.

It may be particularly advantageous if at least one detection device is arranged on at least one injector such that a flame can be detected between at least one orifice opening of an injector element, preferably the inner injector element, and an exit plane of the at least one injector. This makes it easy to check whether the flame extends into or out of the injector.

It can be advantageous if a beam deflection is provided in order to be able to guide both at least one laser beam and a beam to be detected by means of the at least one detection device via an optical path that is at least partially in sections. In this way, by means of only one optical access to the injector, both a coupling of a laser and a coupling-out of a light beam emitted by the flame and to be detected by the detection device can take place. Alternatively or additionally, it can be provided that at least one injector comprises at least two optical accesses in an outer wall.

In one embodiment of the invention, it can be provided that the at least one injection head comprises a plurality of injectors arranged uniformly spaced from one another. As a result, a uniform formation of a flame in the combustion chamber device is possible in a simple manner.

It may be advantageous if at least one control device is provided for controlling the combustion chamber device.

It may be particularly advantageous if at least two injectors are each assigned a laser device, wherein the at least two laser devices are controllable by means of the control device, in particular in terms of time.

Alternatively or additionally, it can be provided that the power and / or the pulse duration of the at least two laser devices can be controlled by means of the control device.

It is favorable if the laser device is arranged on the at least one injector. In this way, the at least one laser beam can be radiated particularly easily into the injector in the common fluid channel.

It is also favorable if the at least one injector comprises a jet entry point, which is arranged on the common fluid channel, in particular in a wall of the common fluid channel. In this way, a direct access to the common fluid channel of the injector is ensured. The invention is further based on the object to provide an engine of the type mentioned, which allows a reliable and multiple executable ignition process for igniting a flame in the engine.

This object is achieved in that a combustion chamber device according to the invention is used.

The engine according to the invention preferably has the advantages already explained in connection with the combustion chamber device according to the invention.

The invention is further based on the object to improve a method for operating a combustion chamber device so that an ignition process for igniting a flame is reliable multiple executable.

This object is achieved in the aforementioned method according to the invention in that a fuel-oxidizer mixture is generated by means of at least one injector for supplying fuel and oxidizer to a combustion chamber, wherein the at least one injector comprises at least one inner injector element and an outer injector element, and a common fluid channel for fluids carried in the inner injector element and in the outer injector element, the common fluid channel opening into the combustion chamber, and at least one laser beam on the fuel-oxidant mixture into the injector into the common fluid channel for igniting same is directed.

The method according to the invention preferably has the features and advantages described above in connection with the combustion chamber device according to the invention and / or the engine according to the invention. By directing a laser beam on the fuel-oxidizer mixture in the injector in the common fluid channel for igniting the fuel-oxidizer mixture ignition is particularly reliable feasible. A laser beam can be repeatedly directed to the fuel-Oxidator- mixture, so that an ignition process with little effort at short intervals is repeatable.

It can be advantageous if at least one laser beam is directed onto a flame-anchoring zone. In this way, a particularly reliable ignition is possible.

Flame anchoring zones (also referred to as flame holding zone, flame anchor point, flame anchoring point, flame anchoring zone or flame stabilization zone) are described, for example, in the article by Singla G. et al., Flame stabilization in high pressure LOx / GH2 and GCH4 combustion.

Proceedings of the Combustion Institute 31, pp. 2215-2222, 2007, and in the article by Matsuyama S. et al., A Numerical Investigation on Shear Coaxial LOX / GH2 Jet Flame at Supercritical Pressure. 44 ^th AIAA Aerospace Sciences Meeting and Exhibit, Reno, NV, 2006.

The flame-retardation zone is the zone in which an ignitable mixture of fuel and oxidizer is formed and from which a stable flame can form after ignition of the mixture.

In an advantageous embodiment of the invention can be provided that fuel and oxidizer are mixed before being fed into a combustion chamber of the combustion chamber device at least partially within an injector. As a result, an advantageous combustion of the fuel is possible. It may be advantageous if fuel and oxidizer are at least partially coaxially guided by means of at least one injector. In this way, a mixture of fuel and oxidizer at an outlet opening is particularly easy to implement.

In particular, it can be provided with coaxial supply of fuel and oxidizer that forms a flame arresting zone in a wake of an inner feed.

A caster is to be understood as the region which is arranged in an inflow direction behind a wall separating the fuel and the oxidizer.

It may be favorable if at least one laser beam is guided at least in sections by means of a light guide. In this way, the at least one laser beam can be guided particularly easily and flexibly within the combustion chamber device.

It can also be advantageous if at least one laser beam is directed transversely to a main axis of at least one injector.

It may be particularly favorable if the at least one laser beam is directed at least approximately perpendicular to a main axis of at least one injector.

On the one hand, it can be provided that at least one laser beam is focused by means of an optical system. In this way, the laser energy required for the ignition can be provided specifically at a specific location.

Alternatively or additionally, it may be provided that at least one laser beam is directed to the fuel-oxidizer mixture in an unfocused manner. In one embodiment of the invention can be provided that by means of a detection device radiation is decoded from at least one area on soft at least one laser beam is directed. As a result, for example, the temperature and / or the density in the region on which the at least one laser beam is directed can be examined.

It can be advantageous if it is checked by means of a detection device whether a laser beam has led to the ignition of the fuel-oxidizer mixture and to the formation of a flame. In this way it is possible to monitor whether an ignition process was successful.

It may also be advantageous, if it is checked after the formation of a flame at regular intervals, whether the flame is extinguished. This makes it particularly easy to check whether unburned fuel-oxidizer mixture flows out.

It may be particularly advantageous if, after extinguishing the flame for re-ignition, a laser beam is directed onto the fuel-oxidizer mixture. Thus, a flame in the combustion chamber device can be restored in a particularly simple way.

It may be favorable if a plurality of laser beams are directed to different areas of the fuel-oxidizer mixture. As a result, ignition can take place at several points.

In particular, it can be provided that an ignition takes place at several points simultaneously.

Alternatively, it can be provided that the laser beams are generated offset in time. As a result, an explosive ignition of the fuel-oxidizer mixture, that is, a substantially simultaneous ignition of the entire mixture and thus the formation of a pressure wave can be prevented. It can be advantageous if the laser beams are controlled by means of a control device. In this way, in particular a temporal offset of the laser beams is easily controllable.

In a preferred embodiment, it is provided that the fuel-oxidizer mixture is photochemically excited by means of the at least one laser beam. In this way, the fuel-oxidizer mixture can be easily ignited.

The combustion chamber device according to the invention is particularly suitable for carrying out the method according to the invention.

The combustion chamber device according to the invention, the method according to the invention for operating a combustion chamber device and the engine according to the invention also have the following advantages:

- Ignition directly at the injection and thus no flame migration and no blowing out of the flame;

Possibility of grouped ignition by a grouped arrangement of injectors with ignition device on the injection head;

- reduction of costs;

- No oversizing of the combustion chamber device necessary because a high ignition safety is ensured;

- high redundancy through multiple ignition locations; - Immediate detection of ignition possible;

- reducing the complexity of the ignition device;

- no need of hypergolic primers and thus avoidance of toxic and aggressive fuels and oxidizers;

- Providing a local variable ignition; - Reduction of the strong pressure shock at the ignition and the associated high load of the combustion chamber device;

- re-ignitability;

- reusability; - reduction of operating risk;

- Ignition directly in the flame-arresting zone and thus immediate flame stabilization; - good adjustability of the ignition location;

- Time and space separate ignition to enable an optimal ignition and starting sequence; and

- Use of only electrical power to ignite the flame and thus avoid additional fuel and corresponding piping and insulation systems.

Combustor devices of the present invention also find application in the chemical and process industries because the quality of a product made in a combustor or using a combustor can be improved by a combustor according to the present invention.

Further features and advantages of the invention are the subject of the following description and the drawings of Ausführungsbei- play.

In the figures show:

Figure 1 is a schematic representation of a first embodiment of an injector of a combustion chamber device;

Figure 2 is a schematic representation of a second embodiment of an injector of a combustion chamber device with a Zündleitrohr; Figure 3a is a schematic representation of a third embodiment of an injector of a combustion chamber device with an optical access;

FIG. 3b shows an enlarged view of the region I in FIG. 3a with flow velocities additionally shown;

FIG. 4 shows a schematic representation of a fourth embodiment of an injector of a combustion chamber device with an optical access and a laser device;

Figure 5 is a schematic representation of a fifth embodiment of an injector of a combustion chamber device with a laser device and a detection device;

Figure 6 is a schematic representation of a sixth embodiment of an injector of a combustion chamber device with two laser devices arranged opposite one another;

Figure 7 is a schematic representation of a seventh embodiment of an injector of a combustion chamber device with obliquely arranged supply of a laser beam;

FIG. 8 shows a schematic representation of an eighth embodiment of an injector of a combustion chamber device with three fluid channels for the supply of fluids;

Figure 9 is a schematic representation of a plan view of a

Front of the third embodiment of an injector of a combustion chamber device according to Figures 3a and 3b; Figure 10 is a schematic representation of a plan view of a

Front side of a ninth embodiment of an injector of a combustion chamber device with two perpendicular to a major axis and perpendicular to each other aligned opti- accesses;

Figure 11 is a schematic representation of a plan view of a

Front of a tenth embodiment of an injector of a combustion chamber device with two perpendicular to a main axis of the injector and at an angle α aligned optical accesses;

Figure 12 is a schematic representation of a plan view of a

Front side of a first embodiment of an injection head of a combustion chamber device with a plurality of injectors and central ignition;

Figure 13 is a schematic representation of a plan view of a

Front side of a second embodiment of an injection head of a combustion chamber device with a plurality of injectors with decentralized ignition;

Figure 14 is a schematic representation of a first embodiment of a staged combustion engine;

Figure 15 is a schematic representation of a second embodiment of an engine, which is used as a gas generator; and

Figure 16 is a schematic representation of a third embodiment of an engine, which can be used as an expander. Identical or functionally equivalent elements are provided in FIGS. 1 to 16 with the same reference numerals.

A combustion chamber device 100 (shown in fragmentary form in FIG. 1) comprises a combustion chamber 102 with a combustion chamber 103 and an injection head 104.

The injection head 104 comprises a plurality of injectors 106. As an example of the number of injectors 106, it should be noted that the known injector head of the Vulcain II engine of the Ariane 5 has five hundred and sixty-six injectors 106. In the upper stage engine VINCI one hundred - twenty two injectors 106 are provided.

A first embodiment of an injector 106 shown in FIG. 1 includes an inner injector element 108 and an outer injector element 110.

The inner injector element 108 is substantially tubular and includes an inner fluid channel 112.

The outer injector element 110 is formed by means of a tube and arranged on a main body 114 of the injector 106.

The inner injector element 108 is arranged inside the outer injector element 110, wherein a main axis 116 of the inner injector element 108 coincides with a main axis 118 of the outer injector element 110 and a main axis 120 of the injector 106. The inner injector element 108 and the outer injector element 110 are arranged coaxially with one another, wherein an outer diameter of the inner injector element 108 is smaller than an inner diameter of the outer injector element 110, so that between the inner injector element 108 and the outer injector element 110 in the radial direction with respect to Main axes 116, 118 and 120 is a free space which forms an outer fluid channel 122.

The inner fluid passage 112 and the outer fluid passage 122 serve to supply fuel and oxidizer to the combustion chamber 102.

In particular, hydrogen, methane and kerosene can serve as fuels. In particular, liquid oxygen is provided as oxidizer in this embodiment. The temperature of the oxygen is, for example, about 90K to about 130K. However, with the use of oxygen for combustor cooling, the temperature of the oxygen as it is supplied to the injector 106 may be higher.

The outer injector element 110 ends at a rear end in an inflow direction E with an orifice opening 124 into the combustion chamber 103.

The orifice 124 of the outer injector 110 is disposed in an exit plane 126 and forms a rear end of the injector 106 in the inflow direction E.

A rear end of the inner injector element 108 in the inflow direction E is designed as a mouth opening 128 of the inner injector element 108.

The orifice 128 of the inner injector element 108 is set back relative to the outlet plane 126 with respect to the inflow direction E by a distance S, that is, offset from the inflow direction E, arranged. Because the inner fluid channel 112 terminates at the orifice 128 of the inner injector element 108 in the inflow direction E before the end of the outer fluid channel 122, a common fluid channel 130 is provided on the injector 106, in which a guided in the inner fluid channel 112 Fluid is at least approximately coaxially guided together with a guided in the outer fluid passage 122 fluid and which opens into the combustion chamber 103.

At least partially, in this common fluid channel 130, the fluid carried in the outer fluid channel 122 and the fluid carried in the inner fluid channel 112 merge.

In this case, a mixing zone 132 forms, which adjoins the mouth opening 128 of the inner fluid channel 112.

The mixing in the mixing zone 132 is promoted in this embodiment of the injector 106 by a chamfer 134 at the rear end in the inflow direction E of the inner injector element 108. Further, a velocity difference between the fuel inflow velocity of about 200 m / s to about 400 m / s and the oxygen inflow velocity of about 20 m / s to about 30 m / s contribute to efficient mixing of fuel and oxidizer.

Since the fluids circulate in the region of the mixing zone 132 due to the resulting shear forces between the fluid jets, the mixing zone 132 is also called the recirculation zone 136. The recirculation zone 136 is arranged directly in the wake of the inner injector element 108.

It may be provided that the fluid guided in the inner fluid channel 112 is an oxidizer and the fluid guided in the outer fluid channel 122 is a fuel. However, it can also be provided that in the inner fluid channel 112, a fuel and in the outer fluid channel 122, an oxidizer is performed.

By using a fuel and an oxidizer as fluids conducted in the injector 106, a fuel-oxidizer mixture, which may be ignitable, results in the mixing zone 132.

A flame generally propagates from this recirculation zone 136 after ignition due to the recirculation of the fluids in the recirculation zone 136. Due to the recirculation of the fluids and the associated reduction of the flow velocities, the flame is "anchored". Therefore, recirculation zone 136 is also referred to as flame trap zone 140.

However, depending on the flow parameters, the recirculation zone 136 may also extend over a greater area than the flame trap zone 140, with the flame anchor zone 140 then being disposed in the recirculation zone 136.

The spatial extent of the flame-retarding zone 140 in the axial direction is generally approximately of the order of magnitude of the radial wall thickness of the inner injector element 108 at its mouth opening 128. For example, the wall thickness is approximately 1 mm at the most.

The spatial extent of the flame anchoring zone 140 in the axial direction is then for example about 1 mm to about 3 mm.

For ignition in the flame-retardant zone 140, a lower ignition energy is required than for ignition further downstream due to lower flow velocities and more favorable mixing ratios. Preferably, ignition occurs within the injector 106.

By means of a flame anchorage, a generally cyclical removal and approach of a flame to the injector 106, ie a flame migration, can be avoided and the flame can thereby be stabilized.

A second embodiment (shown in FIG. 2) of an injector 106 differs from the first embodiment (shown in FIG. 1) in that the injector 106 comprises an ignition tube 142, which serves as an ignition device 138.

An in the inflow direction E behind the end of the Zündleitrohrs 142 is disposed in the exit plane 126 and thus opens at the same height in the combustion chamber 103 as the mouth opening 124 of the outer fluid channel 122nd

By means of the Zündleitrohrs 142, for example, a spark can be introduced into the combustion chamber 103, which ignites a means of the injector 106 introduced into the combustion chamber 103 of the combustion chamber 102 fluid flow.

Incidentally, the second embodiment of an injector 106 (shown in FIG. 2) coincides in terms of structure and function with the first embodiment (shown in FIG. 1), to the above description of which reference is made in this respect.

A third embodiment (shown in FIGS. 3a and 3b) of an injector 106 differs from the first embodiment (shown in FIG. 1) in that an optical access 144 is provided.

The optical access 144 is formed as a passage opening 145 in an outer wall 146 of the outer injector 110. The optical access 144 is arranged in the inflow direction E between the mouth opening 124 of the outer fluid channel 122 and the mouth opening 128 of the inner fluid channel 112.

For guiding light, a light guide 148 is provided in this embodiment. One end of the light guide 148 is arranged so that it is flush with an inner side 150 of the outer wall 146 of the outer injector 110.

The optical waveguide 148 is oriented at least approximately perpendicular to the main axis 116 of the inner injector element 108, the main axis 118 of the outer injector element 110 and the main axis 120 of the injector 106, so that a laser beam directed into the injector 106 by the optical waveguide 148 cross-connects the mixing zone 132 penetrates vertically, at least approximately.

For successful ignition, a laser beam only has to be directed to a mixing zone 132 with an ignitable fuel and oxidizer mixture. This mixing zone 132 does not necessarily have to be a recirculation zone 136 or a flame anchoring zone 140.

However, directing the laser beam at a flame arresting zone 140 may have advantages in ignition safety and flame stability.

In FIG. 3b, the region of the wake of the inner injector element 108 is shown enlarged. To illustrate the flow velocities in this area, arrows are drawn whose lengths symbolically represent the prevailing flow velocities. The velocity curves 153 are shown as an envelope of the punctually prevailing flow velocities in a direction perpendicular to the inflow direction E. It can be seen here that the speed curves 153 have speed minima 155 in the wake of the inner injector element 108. In the area of these velocity minima 155, one by means of a Laser beam generated flame blown out with a very low probability. Rather, a flame stabilizes in this area, so that a stable combustion is guaranteed.

Such a stabilization results, in particular, when the flow velocity in the velocity minimum 155 is lower than the flame velocity.

The laser beam is generated by a laser device (not shown).

The laser parameters required for the initial ignition depend on whether a resonant ignition, that is to say a direct excitation of, for example, oxygen, or a thermal ignition, that is a nonspecific "broadband" excitation, should be effected by means of the laser device.

For example, for resonant ignition and laser-induced photochemical ignition, a laser wavelength of about 130 nm to about 250 nm may be provided. The pulse frequency is, for example, at most 100 Hz. The pulse duration can be approximately 10 ns. For example, the pulse energy in resonant ignition is at most about 50 mJ.

In the case of thermal ignition, it is possible to use a substantially larger wavelength, for example, with commercially available infrared lasers, in particular with diode lasers, and a pulse energy of at most approximately 150 mJ.

An advantage of the resonant ignition is the low ignition energy requirement.

The injector 106 is used in particular for the initial ignition of a flame in a combustion chamber device, that is, the initial ignition by a Fremdzündquelle comprising, for example, a laser device. Extinguishing the flame after an initial ignition is prevented by a suitable arrangement of the injectors 106 and by a suitable choice of the injection conditions.

Incidentally, the third embodiment of an injector (shown in FIGS. 3a and 3b) is identical in construction and function to the first embodiment (shown in FIG. 1), the above description of which is incorporated herein by reference.

A fourth embodiment (shown in FIG. 4) of an injector 106 differs from the third embodiment (shown in FIGS. 3a and 3b) in that a laser device 152 is provided which comprises, for example, at least one laser diode for generating a laser beam.

Laser diodes have the advantages that they are very small and well available and can be installed with little effort.

In contrast to the third embodiment (illustrated in FIGS. 3 a and 3 b) of the injector 106, no light guide 148 is provided in the fourth embodiment (shown in FIG. 4). Instead, an optical system 154 is flush with the inside 150 of the outer wall 146 of the outer injector 110.

However, it can also be provided that the passage opening 145 is filled with a light-transmitting substance.

By means of the optical system 154, a laser beam generated by means of the laser device 152 can be focused.

A focus 156 of the optical system 154 falls into the mixing zone 132 in this embodiment. However, it can also be provided that the laser beam is focused on another area.

Furthermore, the fourth embodiment (shown in FIG. 4) of an injector 106 is characterized in that no chamfering is provided at the rear end of the inner injector element 108 in the inflow direction E.

Incidentally, the fourth embodiment of an injector 106 (shown in FIG. 4) is identical in construction and function to the third embodiment (shown in FIGS. 3a and 3b), to the above description of which reference is made.

A fifth embodiment (shown in FIG. 5) of an injector 106 differs from the fourth embodiment (shown in FIG. 4) in that a beam deflection 160 is arranged in an optical path 158 of the laser beam.

Furthermore, a detection device 162 is provided for the detection of light.

This may in particular comprise a photodiode, a CCD chip and / or a photomultiplier.

For the spectral resolution of the light to be detected, a spectrometer may also be provided.

The beam deflection 160 is arranged in the optical path 158 of the laser beam such that the laser beam and light to be detected by the detection device 162 are guided at least in sections on a common optical path 164 through a common optical access 166 and a common optical system 168. Incidentally, the fifth embodiment of an injector (shown in FIG. 5) is identical in construction and function to the fourth embodiment (shown in FIG. 4), to the above description of which reference is made.

A sixth embodiment of an injector 106 (shown in FIG. 6) substantially corresponds to the fourth embodiment of an injector 106 (shown in FIG. 4), wherein in the sixth embodiment of an injector 106 an optical access 144 with respect to the main axis 116 of the inner injector element 108, the main axis 118 of the outer injector 110 and the main axis 120 of the injector 106 directly opposite second optical access 170 is provided.

By means of this second optical access 170, by means of a second laser device 172 and a second optical system 174, a further laser beam can be focused onto a second focus 176.

Incidentally, the sixth embodiment of an injector 106 (shown in FIG. 6) coincides in terms of structure and function with the fourth embodiment (shown in FIG. 4), to the above description of which reference is made in this respect.

A seventh embodiment of an injector (shown in FIG. 7) essentially corresponds to the third embodiment of an injector (shown in FIGS. 3 a and 3 b), with the difference that the passage opening 145 in the outer wall 146 of the outer injector element 110 is not vertical is aligned with the inside 150 of the outer injector 110, but at an angle α, wherein a centrally guided by the passage opening 145 laser beam with the exit plane 126 includes the angle α. The angle α is in one embodiment in the order of about 30 °, so that a laser beam at this angle in the common fluid channel 130 can be irradiated. The irradiated laser beam intersects the mixing zone 132 in an ignition location 178, which is arranged in the common fluid channel 130.

An irradiation of the laser beam at the angle α serves to circumvent possible structural restrictions in the area of the injector 106 and to reach ignition locations 178 which would not be possible under vertical irradiation. In particular, this may be the case if the distance S is very small, for example smaller than the diameter of the optical access 144.

For additional ignition at an interface 180 in which the laser beam again intersects the mixing zone 132, the energy of the laser beam is generally insufficient.

Incidentally, the seventh embodiment of an injector 106 (shown in FIG. 7) is identical in construction and function to the third embodiment (shown in FIGS. 3a and 3b), the above description of which is incorporated herein by reference.

An eighth embodiment (shown in FIG. 8) of an injector 106 differs from the third embodiment (shown in FIGS. 3a and 3b) in that the injector 106 comprises a central injector element 182 disposed within the outer injector element 110 and the inner one Injector element 108 surrounds.

The central injector element 182 has a substantially tubular shape and has an orifice 184, which is arranged in the inflow direction E between the orifice 124 of the outer injector element 110 and the orifice 128 of the inner injector element 108. The arrangement of the middle injector element 182 between the outer injector element 110 and the inner injector element 108 results in addition to the outer fluid channel 122, which is arranged between the outer injector element 110 and the central injector element 182, and the inner fluid channel 112, which is located inside the inner injector element 108, a central fluid channel 186 which is disposed between the central injector element 182 and the inner injector element 108.

On the inside of a rear end of the central injector element 182 in the inflow direction E, a chamfer 188 is provided, which corresponds essentially to the chamfer 134 of the inner injector element 108.

A main axis 190 of the central injector element 182 coincides with the main axis 116 of the inner injector element 108, the main axis 118 of the outer injector element 110 and the main axis 120 of the injector 106. The injector 106 is thus designed as Trikoaxialinjektor.

Due to the set-back arrangement of the mouth opening 128 of the inner injector element 108 with respect to the mouth opening 184 of the central injector element 182, an opening of the inner fluid channel 112 into the middle fluid channel 186 results, wherein the rear end of the inner injector element 108 in the inflow direction E forms a mixing zone 132.

At the rear end of the central injector element 182 in the inflow direction E, the inner fluid channel 112 finally opens into the outer fluid channel 122 with the middle fluid channel 186. A mixing zone 132 is also formed at the rear end of the central injector element 182 in the inflow direction E. The mixing zones 132 are substantially annular in shape after the ends of the injector elements 108, 182 and are arranged coaxially with one another.

A laser beam irradiated through the optical access 144 into the common fluid channel 130 penetrates twice each of the mixing zones 132, resulting theoretically in total four possible ignition locations 192, which due to the vertical orientation of the optical access 144 all in the common fluid channel 130 within the injector 106th are arranged.

However, only the first ignition location in the direction of irradiation usually has practical relevance, since even here the laser energy is for the most part absorbed.

The eighth embodiment of an injector is particularly suitable for use in pre-combustion chambers or gas generators, wherein either two different components, in particular with central supply of an oxidizer, or three different components are supplied.

Incidentally, the eighth embodiment of an injector 106 (shown in FIG. 8) is identical in construction and function to the third embodiment (shown in FIGS. 3a and 3b), the above description of which is incorporated herein by reference.

From a schematic representation (shown in FIG. 9) of a plan view of the front side of the third embodiment of an injector 106, it can be seen that the main axis 116 of the inner injector element 108, the main axis 118 of the outer injector element 110 and the main axis 120 of the injector 106 coincide. 9, a ninth embodiment of an injector 106 is shown, which substantially corresponds to the third embodiment (shown in FIG. 9) of an injector 106, with the difference that two passage openings 145 in the outer wall 146 of the outer injector 110 are provided, which each form a provided with a light guide 148 optical access 144.

The optical accesses 144 are arranged in this embodiment so that they are aligned relative to each other at a vertical angle and perpendicular to the inflow direction E.

Incidentally, the ninth embodiment of an injector 106 (shown in FIG. 10) is identical in structure and function to the third embodiment (shown in FIGS. 3a, 3b and 9), the above description of which is incorporated herein by reference.

In a tenth embodiment of an injector (shown in FIG. 11), two optical accesses 144 are provided in accordance with the ninth embodiment (shown in FIG. 10), with the difference that the optical accesses 144 are not at a vertical angle relative to one another are aligned at an angle ß to each other.

The angle β in one embodiment is on the order of about 135 °.

Incidentally, the tenth embodiment of an injector 106 (shown in FIG. 11) is identical in construction and function to the third embodiment (shown in FIGS. 3a, 3b and 9), to the above description of which reference is made. FIG. 12 shows a schematic plan view of a first embodiment of an injection head 104 with two hundred five injectors 106 arranged in a symmetrical pattern. A symmetrical pattern usually results in the design of an injection head 104, in particular in the radially outer rows, so that a combustion chamber wall is uniformly loaded during operation of the combustion chamber device 100. In the radially inner region, a uniform spacing of the injectors 106 is generally provided from each other. Due to the consideration of both criteria, therefore, very complex patterns of the injectors 106 usually result.

In this first embodiment of the injection head 104, it is provided that a central injector 106 comprises a laser-based ignition device 138.

For example, with such an injection head 104, it may be provided that the central injector 106 is designed according to the third embodiment (shown in FIGS. 3a, 3b and 9), while the remaining injectors 106 correspond to the first embodiment illustrated in FIG.

A second embodiment of an injection head 104 (shown in FIG. 13) differs from the first embodiment of an injection head 104 (shown in FIG. 12) in that four decentralized injectors 106 are provided which, for example, (shown in FIGS. 3a and 3b) third embodiment and thus each comprise a laser-based ignition device 138. Furthermore, the injection head 104 comprises two hundred and one injectors 106, which essentially correspond to the first embodiment (shown in FIG. 1), that is to say without ignition device 138.

In the second embodiment of the injection head 104 (shown in FIG. 13), the injectors 106 are distributed uniformly on a circle around a main axis 194 of the injection head 104. In this way, a means of the Injectors 106 of the injection head 104 into the combustion chamber 103 of the combustion chamber 102 einströmendes mixture of fuel and oxidizer are ignited locally, which allows a significant reduction caused by the ignition load of the injection head 104 and the entire combustion chamber device 100.

Incidentally, the second embodiment of an injection head 104 (shown in FIG. 13) coincides in terms of structure and function with the first embodiment (shown in FIG. 12), to the above description of which reference is made.

A first embodiment of an engine 196 (shown in FIG. 14) includes a combustor device 100 having an injector head 104 that includes a plurality of injectors (not shown).

The first embodiment of the engine 196 is a rocket engine.

However, it can alternatively also be provided that the engine is an aircraft gas turbine, a stationary gas turbine or an internal combustion engine.

A combustion chamber 103 of a combustion chamber 102, into which the injection head 104 opens, is bounded by a Laval nozzle 198.

The engine 196 further includes an oxidizer feeder 200, a fuel feeder 202 and a turbine 204. An oxidizer pump 206 serves to drive an oxidizer. A fuel pump 208 is for driving a fuel.

Supplying devices 210 are provided for supplying oxidizer and fuel to the turbine 204. Further, feeders 210 are provided to convey oxidizer by means of the oxidizer pump 206 to the injection head 104 of the combustor 100 and a pilot burner 212. From the combustion chamber 103 of the combustion chamber 102, the preburner 212 can be supplied with a gas mixture present in the combustion chamber 103 of the combustion chamber 102 by means of a feed device 210. Gas exiting the preburner 212 may be supplied to the turbine 204 via a feeder 210.

Another feeder 210 is provided for establishing fluid communication between the turbine 204 and the combustor 100.

Further, a supply device 210 is provided to supply fuel to one end of the Laval nozzle 198 by means of the fuel pump 208.

In the first embodiment of an engine 196 (shown in Figure 14), staged combustion is provided. In particular, in this engine 196, pre-combustion takes place in the pre-burner 212. The turbine 204 drives the fuel pump 208 and the oxidizer pump 206. On the one hand, combustion takes place directly at the injection head 104 of the combustion chamber device 100 and, on the other hand, near an exit of the Laval nozzle 198, where fuel is supplied again.

A second embodiment of an engine 196 (shown in FIG. 15) substantially corresponds to the first embodiment of an engine 196 (shown in FIG. 14) having differently arranged feeders 210. In the second embodiment of the engine 196, this engine 196 is operable as a gas generator.

For this purpose, a supply of oxidant by means of the oxidizer 206 to the preburner 212, the combustion chamber device 100 and the turbine 204. By means of the fuel pump 208 is fed via feeders 210 of the turbine 204, the preburner 212 and the end of the Laval nozzle 198 fuel. From the pre-burner 212 gas enters the turbine 204 and is conveyed from there into a central region of the Laval nozzle 198 by means of a further feed device 210.

Furthermore, a return 214 is provided on the combustion chamber device 100 in order to be able to feed gas present in the combustion chamber 103 of the combustion chamber 102 to the injection head 104.

Incidentally, the second embodiment of an engine 196 (shown in FIG. 15) is identical in construction and function to the first embodiment (shown in FIG. 14), to the foregoing description of which reference is made.

A third embodiment of an engine 196 (shown in FIG. 16) differs from the first embodiment (shown in FIG. 14) in that no pre-burner 212 is provided and the supply lines 210 between the oxidizer pump 206 and the combustor 100, between the turbine 204 and the combustor device 100, between the fuel pump 208 and the turbine 204, between the oxidizer pump 206 and the turbine 204 and between the fuel pump 208 and the end of the Laval nozzle 198 are arranged.

In this embodiment, the engine 196 can be operated in particular as an expander.

For this purpose, the oxidizer pump 206 of the combustion chamber device 100 oxidizer is supplied. Gas from the turbine 204 is also supplied to the combustor device 100 with a return line from the combustor device 100 to the turbine 204.

The turbine 204 is supplied with oxidizer and fuel. Further, a supply line 210 is provided to supply fuel by means of the fuel pump 208 to the end of the Laval nozzle 198. Incidentally, the third embodiment of an injector 106 (shown in FIG. 16) is identical in structure and function to the first embodiment (shown in FIG. 14), the above description of which is incorporated herein by reference.

Claims

claims

A combustor apparatus comprising at least one combustion chamber (102), at least one injector head (104) having at least one injector (106) for supplying fuel and oxidizer to a combustion chamber (103) and a laser device (152, 172) for generating at least one laser beam for igniting a fuel-oxidizer mixture, characterized in that the at least one injector (106) comprises at least one inner injector element (108, 182) and an outer injector element (110) and a common fluid channel (130) for in the inner injector element (108, 182) and in the outer injector (110) guided fluids, wherein the common fluid channel (130) opens into the combustion chamber (103), and wherein the at least one laser beam for ignition in the injector (106) in the common fluid channel (130) is irradiated.

2. combustion chamber device according to claim 1, characterized in that the at least one injector (106) at least one fuel injector designed as an injector element (108, 110, 182) for supplying fuel and at least one formed as Oxidatorinjektorelement injector (108, 110, 182) for Supplying oxidizer comprises.

3. combustion chamber device according to claim 1 or 2, characterized in that the inner injector (108, 182) and the outer injector (110) of the at least one injector (106) are arranged coaxially with each other.

4. combustion chamber device according to claim 3, characterized in that at least three injector elements (108, 110, 182) of the at least one injector (106) are arranged tricoaxially to each other.

5. combustion chamber device according to claim 3 or 4, characterized in that the at least one injector (106) comprises at least one injector tube.

6. combustion chamber device according to one of claims 1 to 5, characterized in that at one in an inflow (E) rear end of at least one injector (108, 110, 182) an inner and / or outer chamfer (134, 188) is provided.

7. combustion chamber device according to one of claims 1 to 6, characterized in that the at least one injector (106) opens at an injector opening (124) directly into the combustion chamber (103).

8. combustion chamber device according to one of claims 1 to 7, characterized in that the inner injector (108) opens into the common fluid channel.

9. combustion chamber device according to one of claims 1 to 8, characterized in that at least one orifice (124, 128, 184) of the inner injector (108, 182) against an exit plane (126) of the at least one injector (106) against an inflow ( E) is set back.

10. combustion chamber device according to one of claims 1 to 9, characterized in that the laser device has a laser wavelength such that the fuel-oxidizer mixture by means of the laser device (152, 172) is photochemically excited.

11. combustion chamber device according to one of claims 1 to 10, characterized in that the laser device (152, 172) comprises at least one light guide (148) for guiding the at least one laser beam.

12. combustion chamber device according to one of claims 1 to 11, characterized in that the laser device (152, 172) comprises at least one optical system (154, 168, 174) for focusing the at least one laser beam.

13. A combustion chamber device according to any one of claims 1 to 12, characterized by at least one optical access (144, 170) in an outer wall (146) of the at least one injector (106).

14. combustion chamber device according to claim 13, characterized in that the at least one optical access (144, 170) in a direction parallel to an inflow direction (E) between at least one orifice (124, 128, 184) of an injector (108, 110, 182 ) and an exit plane (126) of the at least one injector (106) is arranged.

15. combustion chamber device according to one of claims 1 to 14, characterized by at least one detection device (162).

16. combustion chamber device according to claim 15, characterized in that the at least one detection device (162) comprises at least one light detector.

17. combustion chamber device according to claim 16, characterized in that the at least one detection device (162) comprises at least one light guide (148).

18. combustion chamber device according to one of claims 15 to 17, characterized in that the at least one detection device (162) is arranged on at least one injector (106) that a flame in the region (132, 136, 140) is detectable, in the ignition of the fuel-oxidizer mixture is effected by means of at least one laser beam.

19. combustion chamber device according to one of claims 15 to 18, characterized in that at least one detection device (162) is arranged on at least one injector (106) that a flame between at least one orifice (124, 128, 184) of an injector (108 , 110, 182) and an exit plane (126) of the at least one injector (106) is detectable.

20. combustion chamber device according to one of claims 15 to 19, characterized in that a beam deflection (160) is provided to at least one laser beam as well as by means of at least one detection device (162) to be detected light beam via an at least partially common optical path (160). 164).

21. combustion chamber device according to one of claims 1 to 20, characterized in that at least one injector (106) at least two optical accesses (144, 170) in an outer wall (146).

22. combustion chamber device according to one of claims 1 to 21, characterized in that the at least one injection head (104) comprises a plurality of evenly spaced from each other arranged injectors (106).

23. combustion chamber device according to one of claims 1 to 22, characterized by a control device for controlling the combustion chamber device (100).

24. combustion chamber device according to claim 23, characterized in that at least two injectors (106) each have a laser device (152, 172) is associated, wherein the at least two laser devices (152, 172) are controllable by means of the control device.

25. combustion chamber device according to one of claims 1 to 24, characterized in that the laser device (152, 172) is arranged on the at least one injector (106).

26. combustion chamber device according to one of claims 1 to 25, characterized in that the at least one injector (106) has a jet entry point, which is arranged on the common fluid channel (130) of the at least one injector (106).

27. An engine, comprising at least one combustion chamber device (100) according to one of claims 1 to 26.

28. A method of operating a combustor device, comprising: generating a fuel-oxidizer mixture by means of at least one injector for supplying fuel and oxidizer to a combustion chamber, the at least one injector comprising at least an inner injector element and an outer injector element, and a common fluid channel for fluids carried in the inner injector element and in the outer injector element, the common fluid channel opening into the combustion chamber; and directing at least one laser beam onto the fuel-oxidizer mixture into the injector into the common fluid channel to ignite the fuel-oxidizer mixture.

29. The method according to claim 28, characterized in that at least one laser beam is directed to a flame arresting zone.

30. The method according to claim 28 or 29, characterized in that fuel and oxidizer are mixed before being fed into a combustion chamber of the combustion chamber device at least partially within an injector.

31. The method according to any one of claims 28 to 30, characterized in that fuel and oxidizer are at least partially coaxially guided by means of at least one injector.

32. The method according to any one of claims 28 to 31, characterized in that at least one laser beam is guided at least in sections by means of a light guide.

33. The method according to any one of claims 28 to 32, characterized in that at least one laser beam is directed transversely to a major axis of the at least one injector.

34. The method according to any one of claims 28 to 33, characterized in that at least one laser beam is focused by means of an optical system.

35. The method according to any one of claims 28 to 34, characterized in that by means of a detection device radiation from at least one region is detected, on soft at least one laser beam is directed.

36. The method according to claim 35, characterized in that it is checked by means of a detection device whether a laser beam has led to the ignition of the fuel-oxidizer mixture and to the formation of a flame.

37. The method of claim 35 or 36, characterized in that is checked after the formation of a flame at regular intervals, whether the flame is extinguished.

38. The method according to claim 37, characterized in that after extinguishing the flame for re-ignition, a laser beam is directed to the fuel-oxidizer mixture.

39. The method according to any one of claims 28 to 38, characterized in that a plurality of laser beams are directed to different areas of the fuel-oxidizer mixture.

40. The method according to claim 39, characterized in that the laser beams are generated offset in time.

41. The method according to claim 39 or 40, characterized in that the laser beams are controlled by means of a control device.

42. The method according to any one of claims 28 to 41, characterized in that the fuel-oxidizer mixture is photochemically excited by means of the at least one laser beam.

43. Use of a combustion chamber device (100) according to one of claims 1 to 26 for carrying out a method according to one of claims 28 to 42.