DE112013005790B4 - Method of operating a combustion system and combustion system - Google Patents

Abstract

In order to provide a method by means of which fuel, in particular fuel-containing exhaust gas from a high-temperature fuel cell device, can be burned safely and reliably, it is proposed that the method comprises the following: supplying fuel to the fuel cell device; discharge of exhaust gas from the fuel cell device, which comprises fuel and preferably has a pressure that is higher than atmospheric pressure; Supplying the exhaust gas from the fuel cell device as one of at least two fluids to a combustion chamber of a combustion chamber device of the combustion device using an injector, the injector comprising an inner fluid channel, an outer fluid channel at least partially surrounding the inner fluid channel and a guide channel, in particular a mixing channel, wherein a first fluid by means of the inner fluid channel and a second fluid by means of the outer fluid channel are fed coaxially to the guide channel with at least approximately the same flow rate, with a supply pressure of the first fluid at least approximately corresponding to a supply pressure of the second fluid.

Description

The present invention relates to a method of operating a combustion system and a combustion system.

The U.S. 2006/0191200 A1 , the EP 2 375 482 A1 , the DE 10 2005 011 005 A1 , the DE 934 118 B , the DE 10 2008 060 560 A1 , the DE 21 31 490 C2 , the DE 1 551 797 A , the DE 102 33 161 A1 , the WO 00/09945 A1 and the JP 2011-089754 A relate to various aspects of burner devices.

Particularly in the case of combustion devices for burning fuel-containing exhaust gas from a high-temperature fuel cell device, reliable operation can be made more difficult, in particular by self-ignition and flashback.

The invention is based on the object of providing a method by means of which fuel, in particular fuel-containing exhaust gas from a high-temperature fuel cell device, can be burned safely and reliably.

• - Zuführen von Brennstoff zu der Brennstoffzellenvorrichtung;
• - Abführen von Abgas aus der Brennstoffzellenvorrichtung, welches Brennstoff umfasst und vorzugsweise einen gegenüber Atmosphärendruck erhöhten Druck aufweist;
• - Zuführen des Abgases aus der Brennstoffzellenvorrichtung als eines von mindestens zwei Fluiden zu einem Brennraum einer Brennkammervorrichtung der Verbrennungsvorrichtung unter Verwendung eines Injektors, wobei der Injektor einen inneren Fluidkanal, einen den inneren Fluidkanal zumindest abschnittsweise umgebenden äußeren Fluidkanal und einen Führungskanal, insbesondere Mischkanal, umfasst,

wobei ein erstes Fluid mittels des inneren Fluidkanals und ein zweites Fluid mittels des äußeren Fluidkanals koaxial mit zumindest näherungsweise gleicher Strömungsgeschwindigkeit dem Führungskanal zugeführt werden,
wobei ein Versorgungsdruck des ersten Fluids zumindest näherungsweise einem Versorgungsdruck des zweiten Fluids entspricht.This object is achieved according to the invention by a method for operating a combustion system, wherein the combustion system comprises a fuel cell device designed, for example, as a high-temperature fuel cell device and a combustion device for burning fuel-containing exhaust gas from the fuel cell device. According to the invention, the method comprises the following:

• - supplying fuel to the fuel cell device;
• - Discharge of exhaust gas from the fuel cell device, which comprises fuel and preferably has a pressure that is higher than atmospheric pressure;
• - Supplying the exhaust gas from the fuel cell device as one of at least two fluids to a combustion chamber of a combustion chamber device of the combustion device using an injector, the injector comprising an inner fluid channel, an outer fluid channel at least partially surrounding the inner fluid channel and a guide channel, in particular a mixing channel,

a first fluid being fed coaxially to the guide channel by means of the inner fluid channel and a second fluid by means of the outer fluid channel with at least approximately the same flow rate,
wherein a supply pressure of the first fluid corresponds at least approximately to a supply pressure of the second fluid.

The method according to the invention for operating a combustion system preferably has one or more features and/or advantages of the combustion device described below, the combustion system described below and/or the method described below for supplying two fluids to a combustion chamber of a combustion chamber device.

In one embodiment of the invention, it is provided that using the injector, an oxidizer is supplied as a further fluid of the at least two fluids to the combustion chamber of the combustion chamber device.

A pressure of the oxidizer before it is fed to the injector is preferably increased by means of a compressor device of a gas turbine device of the combustion device and/or by means of a separate compressor device such that the pressure of the oxidizer corresponds at least approximately to the pressure of the fuel-containing exhaust gas from the fuel cell device.

The oxidizer is in particular air.

It can be favorable if the combustion device comprises a plurality of injectors, by means of which the at least two fluids are supplied to the combustion chamber, fluid flows with volume flows and/or mass flows that differ from one another being supplied to the injectors.

In particular, when the injectors are supplied with fluid flows having volume flows and/or mass flows that differ from one another, regions with different mixing ratios of the at least two fluids can be formed in the combustion chamber. As a result, the reliability and safety of the combustion can be increased.

It can be favorable if a partial flow of a total anode waste gas flow from the fuel cell device is supplied to the combustion device as one of the at least two fluids.

As an alternative or in addition to this, provision can be made for a partial flow of a total cathode exhaust gas flow from the fuel cell device to be supplied to the combustion device as one of the at least two fluids.

It can be advantageous if anode exhaust gas from the fuel cell device is supplied as one of the at least two fluids and cathode exhaust gas from the fuel cell device is supplied to the combustion device as another of the at least two fluids.

For example, it can be provided that only two fluids are supplied, with one of the two fluids being exclusively anode waste gas from the fuel cell device and one of the two fluids being exclusively cathode waste gas from the fuel cell device of the combustion device.

It can be favorable if the at least two fluids are fed from the fuel cell device to the guide channel in such a way that the at least two fluids between the fuel cell device and the guide channel have at least approximately the same total pressure loss.

It can be provided that the at least two fluids are supplied to the combustion device with at least approximately identical pressure.

In particular, it can be provided that the at least two fluids are supplied to the combustion device with at least approximately identical supply pressure.

Within the combustion device, the at least two fluids preferably have at least approximately the same pressure loss, in particular until they reach the combustion chamber.

A fluid, which is supplied as one of at least two fluids, preferably comprises ambient air from an environment of the combustion system or is formed by ambient air from an environment of the combustion system.

Ambient air is in particular air that has not been passed through the fuel cell device.

By means of a combustion device, preferably fuel-containing exhaust gas from a high-temperature fuel cell device can be safely and reliably burned.

• - eine Brennkammervorrichtung, welche einen Brennraum umfasst, und
• - einen Injektor zum Zuführen von Brennstoff und Oxidator zu dem Brennraum,

wobei der Injektor einen inneren Fluidkanal, einen den inneren Fluidkanal zumindest abschnittsweise umgebenden äußeren Fluidkanal und einen bezüglich einer Strömungsrichtung stromabwärts des inneren Fluidkanals angeordneten Führungskanal umfasst,
wobei der äußere Fluidkanal einen sich verjüngenden Abschnitt umfasst, in welchem die Querschnittsfläche des äußeren Fluidkanals längs einer Strömungsrichtung von Fluiden in dem Injektor abnimmt,
wobei der innere Fluidkanal und der äußere Fluidkanal in einem Bereich in den Führungskanal münden, in welchem die Querschnittsfläche des inneren Fluidkanals, des äußeren Fluidkanals und/oder des Führungskanals minimal ist, wobei eine Querschnittsfläche des Führungskanals ausgehend von einem dem Brennraum zugewandten Ende des inneren Fluidkanals längs der Strömungsrichtung im Wesentlichen konstant ist oder zunimmt.The combustion device for burning fuel-containing exhaust gas of a high-temperature fuel cell device preferably comprises the following:

• - a combustor device comprising a combustion chamber, and
• - an injector for supplying fuel and oxidizer to the combustion chamber,

wherein the injector comprises an inner fluid channel, an outer fluid channel surrounding the inner fluid channel at least in sections, and a guide channel arranged downstream of the inner fluid channel with respect to a flow direction,
wherein the outer fluid passage includes a tapered portion in which the cross-sectional area of the outer fluid passage decreases along a flow direction of fluids in the injector,
wherein the inner fluid channel and the outer fluid channel open into the guide channel in a region in which the cross-sectional area of the inner fluid channel, the outer fluid channel and/or the guide channel is minimal, with a cross-sectional area of the guide channel starting from an end of the inner fluid channel facing the combustion chamber is substantially constant or increasing along the direction of flow.

In this specification and the appended claims, a high-temperature fuel cell device is to be understood in particular as a solid oxide fuel cell (SOFC) device.

A guide channel of the injector is in particular a section of the injector in which at least two fluids are guided together and without being separated from one another.

In principle, the at least two fluids can thus be thoroughly mixed in the guide channel. The guide channel is then in particular a mixing channel. Depending on a selected flow rate of the fluids, however, it can also be provided that mixing takes place only to a very limited extent, for example only in the area of a shear layer between the at least two fluids.

The inner fluid channel and the outer fluid channel can, for example, be arranged offset in relation to one another coaxially or parallel.

The cross-sectional area of the outer fluid channel preferably decreases continuously and/or steadily in the tapering section.

In particular, the tapered portion of the outer fluid passage preferably has no region in which the cross-sectional area increases along the direction of flow.

Preferably, one fluid is a fuel and another fluid is an oxidizer.

Provision can be made for the fuel to be guided in the inner fluid channel or in the outer fluid channel. Accordingly, it can be provided that the oxidizer is guided in the outer fluid channel or in the inner fluid channel.

A cross-sectional area of the guide channel in an opening area of the inner fluid channel and the outer fluid channel preferably corresponds at most approximately to the sum of the cross-sectional areas of the inner fluid channel and the outer fluid channel at their ends facing the combustion chamber.

The guide channel preferably comprises an expanding section in which the cross-sectional area of the guide channel increases along the direction of flow, in particular steadily and/or continuously.

In the widening section of the guide channel, there preferably does not exist a region in which the cross-sectional area increases along the direction of flow.

In one embodiment of the invention, it is provided that the guide channel consists exclusively of the widening section and the widening section preferably extends from an end of the inner fluid channel facing the combustion chamber to an end of the injector facing the combustion chamber.

An expanding section of the guide channel, in which the cross-sectional area of the guide channel increases continuously and/or steadily along the direction of flow, preferably has no steps, edges or projections. Undesirable turbulence and/or detachment of a fluid flow can thus be prevented.

It can be favorable if the guide channel comprises one or more constant sections with cross-sectional areas that are essentially constant in each case along the direction of flow.

Preferably, the guide channel comprises at least two constant sections each having a substantially constant cross-sectional area along the flow direction, the at least two constant sections being arranged one after the other along the flow direction, so that an upstream constant section of the guide channel has a first cross-sectional area and a constant section arranged upstream constant section following, downstream arranged constant section of the guide channel are provided with a second cross-sectional area, wherein the second cross-sectional area is larger than the first cross-sectional area.

A transition area between the upstream constant section of the guide channel and the downstream constant section of the guide channel is preferably formed by an abrupt cross-sectional enlargement, a step and/or by a plane depression, for example a milled plane depression forming the downstream constant section.

It can be favorable if the guide channel comprises at least two consecutive sections which have a common axis of symmetry and/or central axis.

As an alternative or in addition to this, it can be provided that the guide channel comprises at least two consecutive sections which have axes of symmetry and/or central axes that differ from one another.

It can be favorable if the guide channel comprises at least two consecutive sections which have axes of symmetry and/or central axes running essentially parallel to one another.

It can be provided that an end of the guide channel that is arranged downstream with respect to the direction of flow of the fluids, in particular a constant section or a widening section of the guide channel, opens into the combustion chamber of the combustion chamber device.

One embodiment of the invention provides that a wall of the inner fluid channel, a wall of the outer fluid channel and/or one or more walls of one or more middle fluid channels and/or a wall of the guide channel have a roughened surface at least in sections.

A roughened surface is to be understood in particular as a surface which has been specifically machined to increase the roughness, for example provided with a thread.

It can be favorable if a wall of the inner fluid channel is provided with a roughened surface at least in sections on an inside facing the fluid guided therein and/or on an outside facing away from the fluid guided therein.

In particular, it can be provided that the inner fluid duct, the outer fluid duct, one or more middle fluid ducts and/or the guide duct at the respective end facing the combustion chamber of the combustion chamber device, in particular at an end region facing the combustion chamber, are at least partially covered by a wall with a roughened surface are formed.

It can be advantageous if the combustion device comprises a gas turbine device.

The combustor device may be, for example, a combustor device of the gas turbine device.

Alternatively or in addition to this, it can be provided that the combustion chamber device is a combustion chamber device that is different from a combustion chamber device of the gas turbine device.

It can be advantageous if at least one section of the guide channel or the entire guide channel has a length which at most approximately corresponds to the product of the average flow velocity of the fluids in the section of the guide channel or in the entire guide channel and the ignition delay time of a mixture of the fluids. In this way, the injector can be prevented from being damaged by a flashback.

It can be provided that the injector comprises one or more central fluid channels, which at least partially surround the inner fluid channel and are surrounded at least partially by the outer fluid channel.

The inner fluid duct, the outer fluid duct and the one middle fluid duct or the several middle fluid ducts are preferably arranged coaxially or offset in parallel to one another.

In particular, the inner fluid channel, the outer fluid channel and the one or more central fluid channels have a common axis of symmetry and/or central axis.

Preferably, the inner fluid channel, the outer fluid channel and/or the one or more central fluid channels each have one or more tapered sections.

Preferably, the inner fluid channel, the outer fluid channel and/or the one or more middle fluid channels are arranged relative to one another and/or designed in such a way that the inner fluid channel, the outer fluid channel and/or the one or more middle fluid channels do not widen Include portion in which the cross-sectional area increases along the direction of flow.

Preferably, tapered sections of the inner fluid channel, the outer fluid channel and/or the one or more central fluid channels are arranged adjacent to one another with respect to a direction perpendicular to the direction of flow.

In particular, it can be provided that a tapering section of the outer fluid channel surrounds a tapering section of the one or more central fluid channels and/or a tapering section of the inner fluid channel, for example in a ring shape.

In one embodiment of the invention, it is provided that the combustion device comprises a plurality of injectors, in particular a plurality of injectors of the same size and/or of different sizes.

Provision can be made for the injectors to be arranged in a uniformly distributed manner on a feed head of the combustion chamber device, in particular in order to uniformly supply the combustion chamber of the combustion chamber device with fluid, in particular fuel and oxidizer.

However, it can be advantageous if the injectors are arranged in an unevenly distributed manner on the feed head of the combustion chamber device. As a result, the fluids, in particular the fuel and the oxidizer, can be supplied non-uniformly to the combustion chamber of the combustion chamber device, as a result of which more reliable and/or safer ignition and/or combustion can take place.

The combustion device is particularly suitable for use in a combustion system.

The present invention also relates to a combustion system.

In this respect, the invention is based on the object of providing a combustion system by means of which, in particular, fuel-containing exhaust gas from a high-temperature fuel cell device can be burned safely and reliably.

This object is achieved according to the invention by a combustion system which, for example, as a high-temperature fuel cell device formed fuel cell device and a combustion device for burning fuel-containing exhaust gas of the fuel cell device comprises.

Preferably, the combustor comprises a combustor comprising a combustion chamber and an injector for supplying fuel and oxidizer to the combustion chamber.

The injector preferably comprises an inner fluid channel, an outer fluid channel surrounding the inner fluid channel at least in sections, and a guide channel arranged downstream of the inner fluid channel with respect to a flow direction.

The guide channel preferably opens into the combustion chamber.

An anode exhaust gas line of the fuel cell device and/or a cathode exhaust gas line of the fuel cell device is preferably fluidically connected to the injector, so that an anode exhaust gas stream and/or a cathode exhaust gas stream of the fuel cell device can be fed to the combustion chamber by means of at least one fluid channel of the injector.

It can be favorable if a first fluid can be fed to the guide channel coaxially by means of the inner fluid channel and a second fluid by means of the outer fluid channel with at least approximately the same flow rate.

A supply pressure of the first fluid preferably corresponds at least approximately to a supply pressure of the second fluid.

The combustion system, in particular the combustion device and the fuel cell device, are preferably designed and/or set up and/or connected to one another in such a way that the fluids can be supplied to the guide channel at at least approximately the same flow rate and/or that a supply pressure of the first fluid is at least approximately the same as a supply pressure of the second fluid corresponds.

It can be favorable if the anode exhaust gas line of the fuel cell device is fluidly connected to a first fluid channel of the injector and the cathode exhaust gas line of the fuel cell device is fluidically connected to a second fluid channel of the injector, the anode exhaust gas stream and the cathode exhaust gas stream being able to be combined by means of the injector and can be supplied together to the combustion chamber.

The combustion system preferably comprises a fluid duct, by means of which a fluid stream, which preferably has a pressure that is higher than atmospheric pressure, can be fed as a fuel stream with excess fuel to the fuel cell device, then at least partially as a fuel stream by means of the injector can be fed to the combustion chamber and then via a turbine device to a gas turbine device Combustion device can be relaxed.

It can be provided that the combustion device comprises a gas turbine device and that the combustion chamber device is a combustion chamber device of the gas turbine device.

At least one section of the guide channel, in particular the entire guide channel, preferably has a length which at most approximately corresponds to the product of the average flow velocity of the fluids in this section or in the entire guide channel and the ignition delay time of a mixture of the fluids.

In one embodiment of the invention, it can be provided that the combustion system comprises a compressor device, by means of which a supply pressure of a fluid to be supplied to the combustion chamber by means of the injector can be adapted, in particular adapted, to a supply pressure of a fluid which is discharged from the fuel cell device and also to be supplied to the combustion chamber by means of the injector. is.

Alternatively or in addition to this, it can be provided that the combustion system comprises a compressor device, by means of which a flow rate of a fluid as it flows into the guide channel can be adjusted, in particular adjusted, to a flow rate of a further fluid, the further fluid being in particular a fluid discharged from the fuel cell device and is also fluid to be supplied to the combustion chamber by means of the injector.

A supply pressure is in particular a pressure of a fluid present at a connection of the combustion device.

Furthermore, it can be provided that a supply pressure is a pressure of a fluid at an outlet of the fuel cell device.

In this specification and the appended claims, the wording “at least approximately” and/or “substantially” means in particular a deviation of no more than approx approximately 50%, for example at most approximately 20%, in particular at most approximately 10%, preferably at most approximately 5%.

In the method according to the invention, there is preferably no injection of a first fluid into a second fluid. Rather, it is preferably provided that two fluids are fed uniformly together to a guide channel and are fed to the combustion chamber by means of the guide channel.

A coaxial supply with the same or only minimally different flow speeds is preferably provided.

This results in particular in very weak shear layers at most, so that at most there is very slight mixing (in particular due to diffusion and low shear forces).

In particular, the combination of the at least two fluids does not take place as in the case of a diffusion burner.

Preferably, a recirculation-free and shear layer-free coaxial flow feed is realized with an air jacket layer in order to feed highly reactive fluids, in particular exhaust gas containing fuel, to the combustion chamber. Preferably, stabilization does not occur at one end of the inner fluid channel (middle nozzle).

The principle of pure diffusion combustion is preferably avoided. In particular, sufficiently hot combustion chamber exhaust gas is mixed upstream of the heat release zone into the air jacket layer and/or into the supplied fuel-containing fluid in order to stabilize the flame and lower the combustion temperature through inerting.

The injector is preferably designed such that the fluid supplied by means of the inner fluid channel is surrounded in the guide channel with as little disruption as possible by the fluid supplied by means of the outer fluid channel and can be fed to the combustion chamber with as little disruption as possible.

In particular, when cathode exhaust gas and anode exhaust gas are supplied as fluids from the fuel cell device, the fluid pressures, in particular the supply pressures, are preferably chosen to be the same, so that damage to the fuel cell device due to excessive pressure gradients can be prevented.

The combustion system, in particular the combustion device, is preferably designed in such a way that there is a high level of safety against flashback. In particular, a mixing or merging of the fluids at the narrowest point of the injector is provided for this purpose.

A mixing zone that is virtually free of recirculation and without surface jumps or other disturbances in the vicinity of the injector is preferably provided.

By means of an undisturbed air jacket layer and a predetermined length of the guide channel (mixture length), it is preferably possible to ensure that no pure diffusion burner is created and that flame stabilization takes place at the earliest at the area jump in the area of the combustion chamber entry and/or during or after the mixing of combustion exhaust gas.

The maximum flow speeds of the at least two fluids when they are supplied to the guide channel are preferably at least approximately identical.

Flow guidance of the fuel cell system is preferably designed in such a way that, starting from the fuel cell device to the combustion chamber, the same pressure losses prevail in both fluid flows until they meet (in the guide channel), in particular in order to design the pressure reaction on the fuel cell device in such a way that there is no pressure difference between the anode side and the cathode side .

Identical pressures are preferably present at the fuel cell outlets in particular.

In principle, it can be provided that the anode exhaust gas line is fluidically connected to an inner, an outer or a central fluid channel, so that a fluid configured as an anode exhaust gas flow can be supplied to the combustion chamber by means of the inner fluid channel, the outer fluid channel or the central fluid channel .

Furthermore, it can be provided that the cathode exhaust gas line is fluidically connected to the inner, the outer and/or the central fluid channel, so that a fluid configured as a cathode exhaust gas stream can be fed to the combustion chamber by means of the inner, the outer and/or the central fluid channel is.

The combustion system according to the invention preferably has one or more features and/or advantages of the combustion device.

It can be favorable if the anode exhaust gas line of the fuel cell device a first fluid channel of the injector and the cathode exhaust gas line of the fuel cell device is fluidically connected to a second fluid channel of the injector, so that the anode exhaust gas stream and the cathode exhaust gas stream can be combined by means of the injector and, in particular together, can be fed to the combustion chamber.

The first fluid channel and the second fluid channel are preferably different fluid channels, for example the inner fluid channel and the outer fluid channel.

It can be favorable if the gas turbine device comprises a compressor device, by means of which the fuel stream can be compressed before it is fed to the fuel cell device and/or an oxidizer stream can be compressed before it is fed to the fuel cell device.

In particular, it can be provided that an oxidant flow and/or a fuel flow can be compressed by means of the compressor device in such a way that the oxidant flow and/or the fuel flow in the fuel cell device have essentially the same pressure.

The combustion system according to the invention is particularly suitable for carrying out a method for supplying two fluids to a combustion chamber of a combustion chamber device.

A method for supplying two fluids to a combustion chamber of a combustion chamber device is also described here.

The method for supplying two fluids to a combustion chamber of a combustion chamber device is preferably carried out using an injector, the injector comprising an inner fluid channel, an outer fluid channel at least partially surrounding the inner fluid channel and a guide channel. In particular, a first fluid is supplied to the guide channel by means of the inner fluid channel and a second fluid by means of the outer fluid channel in a region of the injector in which a flow rate of the first fluid and/or the second fluid is at a maximum.

A pressure of the first fluid preferably corresponds at least approximately to a pressure of the second fluid.

Preferably, the outer fluid passage includes a tapered portion in which the cross-sectional area of the outer fluid passage decreases along a flow direction of fluids in the injector. This increases the flow speed of the fluid guided in the outer fluid channel. A guide channel of the injector, which follows the inner fluid channel and/or the outer fluid channel, i.e. which is arranged downstream of the inner fluid channel and/or the outer fluid channel, preferably has a cross-sectional area which is constant or increases along the direction of flow. In the guide channel of the injector, the flow speed of the fluids guided therein remains essentially constant or is reduced.

The first fluid or the second fluid can be, for example, an in particular gaseous fuel, in particular fuel-containing exhaust gas of a high-temperature fuel cell device. Accordingly, the second fluid or the first fluid is preferably an oxidizer, for example air or oxygen-containing exhaust gas from a high-temperature fuel cell device.

The method for supplying two fluids to a combustion chamber of a combustion chamber device using an injector preferably has one or more features and/or advantages of the combustion device and/or the combustion system according to the invention.

The combustion device and/or the combustion system preferably have a control device for controlling the combustion device or the combustion system.

In particular, the control device is designed and set up in such a way that one or more of the method steps mentioned in this description and/or the appended claims can be carried out by means of the combustion device and/or the combustion system.

• Als ein Fluid kann beispielsweise wasserstoffhaltiges Abgas einer Brennstoffzellenvorrichtung verwendet werden.

The combustion device, the combustion system, the method for supplying two fluids to a combustion chamber and/or the method for operating a combustion system can also have one or more of the features and/or advantages described below:

• For example, hydrogen-containing exhaust gas from a fuel cell device can be used as a fluid.

At least one fluid preferably has a temperature of at least approximately 200° C., for example at least approximately 400° C., in particular at least approximately 600° C., before it is supplied to the injector.

Preferably, there is only a small, in particular no, pressure difference between the Fluids, in particular between a fuel flow and an oxidation flow.

Especially with the premixing or partial premixing of fuel and oxidizer, there is a high risk of flashback and auto-ignition.

In particular, when a fuel flow has a relatively low pressure, a high inflow velocity into a combustion chamber cannot be realized to minimize the risk of auto-ignition and flashback. These disadvantages are preferably compensated for by the invention or do not occur.

Preferably, two fluids, in particular the fuel and the oxidizer, are brought together and/or mixed at a point of maximum flow velocity.

The at least two fluids, in particular the fuel and the oxidizer, preferably have essentially the same pressure.

Preferably, neither cooling of the oxidizer, e.g. air, nor high fuel supply pressure are required.

It can be advantageous if an injector and/or a feed head of the combustion chamber device comprises a discontinuity in area, in particular a discontinuity in cross-sectional area, by means of which a recirculation zone, for example an exhaust gas recirculation zone, can be formed. As a result, a flame front can preferably be stabilized by self-ignition effects due to the hot fluids, in particular the hot exhaust gas.

The length of a guide channel of the injector is preferably selected in such a way that no self-ignition can take place within the guide channel.

The invention is particularly suitable for the combustion of highly reactive fuels.

The use of the combustion device, in particular the injector of the combustion device, preferably results in a very low pressure loss.

A convex design of the guide channel, in particular a guide channel that widens along the direction of flow, can preferably be used to recover pressure.

Preferably, a transition between an end of the injector facing the combustion chamber and an exit surface of a feed head of the combustion chamber device in which the injector is arranged is not perpendicular.

For example, it can be provided that an end of the injector facing the combustion chamber and an exit surface of a feed head of the combustion chamber device, in which the injector is arranged, have surfaces which enclose an angle of at least approximately 120°, for example at least approximately 135°, with one another.

The formation of backflow areas in a mixing zone, in particular in the guide channel, is preferably prevented by clear tear-off edges, in particular at an end of the inner fluid channel facing the combustion chamber.

A first fluid is preferably injected into the second fluid with a jet-in-coflow arrangement, ie with an injection angle β=0° or with a very small injection angle of one or more further fluids (β<<90°).

Self-ignition at the site of the mixture, in particular in the guide channel, is preferably prevented by injection without a backflow.

The risk of flashback is preferably minimized.

The guide channel preferably has a convex shape in the region of the exit into the combustion chamber, so that pressure recovery is possible due to the Coanda effect.

Mixing of the fluids can be improved by using microturbulators, in particular in order to generate small-scale vortices and thus a low pressure loss in a mixing zone, in particular in the guide channel.

A fluid, in particular an oxidizer, is divided, for example, for cooling and/or for setting a desired gas composition in the guide channel (so-called air split).

The injectors are preferably arranged in a circular ring to form an exhaust gas recirculation zone or distributed over the entire feed head.

It can be provided that the feed head in the area of the injectors with plane depressions is provided to create small exhaust gas recirculation zones.

The invention is particularly suitable for afterburning in fuel cell devices, for use in combustion chamber technology, in power plant technology and/or energy technology, and for mixing and/or burning highly reactive fluids, in particular for hydrogen combustion.

Further preferred features and/or advantages of the invention are the subject of the following description and the graphic representation of exemplary embodiments.

• 1 eine schematische Darstellung einer ersten Ausführungsform eines Verbrennungssystems, welches eine Brennstoffzellenvorrichtung, eine Gasturbinenvorrichtung und eine separate Brennkammervorrichtung umfasst;
• 2 eine der 1 entsprechende schematische Darstellung einer zweiten Ausführungsform eines Verbrennungssystems, wobei die Brennkammervorrichtung eine Brennkammervorrichtung der Gasturbinenvorrichtung ist;
• 3 einen schematischen Längsschnitt durch eine erste Ausführungsform eines Injektors einer Verbrennungsvorrichtung, bei welchem ein innerer Fluidkanal und ein äußerer Fluidkanal vorgesehen sind, welche in einen Führungskanal des Injektors münden;
• 4 eine der 3 entsprechende schematische Darstellung der ersten Ausführungsform des Injektors, wobei eine andere Betriebsweise dargestellt ist;
• 5 eine der 3 entsprechende schematische Darstellung einer zweiten Ausführungsform eines Injektors, bei welchem mehrere Oberflächen aufgeraut sind;
• 6 eine der 3 entsprechende schematische Darstellung einer dritten Ausführungsform eines Injektors, welcher einen sich erweiternden Führungskanal umfasst;
• 7 eine schematische Darstellung eines einem Brennraum einer Brennkammervorrichtung der Verbrennungsvorrichtung zugewandten Endes einer Wandung eines inneren Fluidkanals, bei welcher eine Anfasung vorgesehen ist, so dass das Ende konisch ausgebildet ist;
• 8 eine der 7 entsprechende schematische Darstellung einer alternativen Ausführungsform des dem Brennraum zugewandten Endes der Wandung des inneren Fluidkanals, wobei die Wandung eine abgerundete Außenseite aufweist;
• 9 eine der 3 entsprechende schematische Darstellung einer vierten Ausführungsform eines Injektors, bei welchem ein mittlerer Fluidkanal zwischen dem inneren Fluidkanal und dem äußeren Fluidkanal angeordnet ist;
• 10 eine schematische Schnittdarstellung eines Teils eines Brennraums der Brennkammervorrichtung samt einer daran angrenzenden Brennraumwandung und eines Abschnitts des Zuführkopfs;
• 11 eine der 3 entsprechende Schnittdarstellung einer fünften Ausführungsform eines Injektors, bei welchem ein sich stufenförmig erweiternder Führungskanal vorgesehen ist;
• 12 eine der 3 entsprechende schematische Darstellung einer sechsten Ausführungsform eines Injektors, bei welchem ein exzentrisch zu dem inneren Fluidkanal und dem äußeren Fluidkanal angeordneter Abschnitt des Führungskanals vorgesehen ist;
• 13 eine schematische Draufsicht auf eine erste Ausführungsform eines Zuführkopfs der Brennkammervorrichtung, bei welcher die Injektoren ungleichmäßig verteilt angeordnet sind;
• 14 eine der 13 entsprechende schematische Draufsicht auf eine zweite Ausführungsform eines Zuführkopfs, bei welcher die Injektoren kreisförmig angeordnet sind;
• 15 eine der 13 entsprechende schematische Draufsicht auf eine dritte Ausführungsform eines Zuführkopfs, bei welcher die Injektoren gleichmäßig verteilt an dem Zuführkopf angeordnet sind, jedoch ungleichmäßig betrieben werden;
• 16 eine der 13 entsprechende schematische Draufsicht auf eine vierte Ausführungsform eines Zuführkopfs, wobei eine ringförmige Öffnung für einen Luftmantelstrom vorgesehen ist;
• 17 einen Schnitt durch den Zuführkopf aus 16 längs der Linie 17 - 17 in 16;
• 18 eine der 13 entsprechende schematische Darstellung einer fünften Ausführungsform eines Zuführkopfs, bei welcher ringförmig angeordnete Kühlluftkanäle vorgesehen sind;
• 19 eine der 17 entsprechende Schnittdarstellung durch die fünfte Ausführungsform des Zuführkopfs gemäß 18 längs der Linie 19 - 19 in 18;
• 20 eine der 13 entsprechende schematische Draufsicht auf eine sechste Ausführungsform eines Zuführkopfs, mit alternativer Anordnung der Injektoren und der Kühlluftkanäle; und
• 21 eine der 3 entsprechende schematische Darstellung einer siebten Ausführungsform eines Injektors, bei welchem ein innerer Fluidkanal außermittig in einem äußeren Fluidkanal angeordnet ist.

In the drawings show:

• 1 a schematic representation of a first embodiment of a combustion system, which comprises a fuel cell device, a gas turbine device and a separate combustion chamber device;
• 2 one of the 1 corresponding schematic representation of a second embodiment of a combustion system, wherein the combustor device is a combustor device of the gas turbine device;
• 3 a schematic longitudinal section through a first embodiment of an injector of a combustion device, in which an inner fluid channel and an outer fluid channel are provided, which open into a guide channel of the injector;
• 4 one of the 3 corresponding schematic representation of the first embodiment of the injector, wherein a different mode of operation is shown;
• 5 one of the 3 corresponding schematic representation of a second embodiment of an injector, in which several surfaces are roughened;
• 6 one of the 3 corresponding schematic representation of a third embodiment of an injector, which comprises an expanding guide channel;
• 7 a schematic representation of a combustion chamber of a combustion chamber device of the combustion device facing end of a wall of an inner fluid channel, in which a chamfer is provided so that the end is conical;
• 8th one of the 7 corresponding schematic representation of an alternative embodiment of the end of the wall of the inner fluid channel facing the combustion chamber, the wall having a rounded outer side;
• 9 one of the 3 corresponding schematic representation of a fourth embodiment of an injector, in which a middle fluid channel is arranged between the inner fluid channel and the outer fluid channel;
• 10 a schematic sectional view of part of a combustion chamber of the combustion chamber device together with a combustion chamber wall adjacent thereto and a section of the feed head;
• 11 one of the 3 corresponding sectional view of a fifth embodiment of an injector, in which a step-wise widening guide channel is provided;
• 12 one of the 3 corresponding schematic representation of a sixth embodiment of an injector, in which a section of the guide channel is provided which is arranged eccentrically to the inner fluid channel and the outer fluid channel;
• 13 a schematic plan view of a first embodiment of a feed head of the combustion chamber device, in which the injectors are arranged unevenly distributed;
• 14 one of the 13 corresponding schematic plan view of a second embodiment of a feed head, in which the injectors are arranged in a circle;
• 15 one of the 13 corresponding schematic plan view of a third embodiment of a feed head, in which the injectors are distributed evenly on the feed head, but are operated unevenly;
• 16 one of the 13 corresponding schematic plan view of a fourth embodiment of a feeding head, wherein an annular opening is provided for an air sheath flow;
• 17 cut through the feed head 16 along line 17 - 17 in 16 ;
• 18 one of the 13 corresponding schematic representation of a fifth embodiment of a feed head, in which annularly arranged cooling air ducts are provided;
• 19 one of the 17 corresponding sectional view through the fifth embodiment of the feed head according to 18 along line 19 - 19 in 18 ;
• 20 one of the 13 corresponding schematic plan view of a sixth embodiment form of a feed head, with an alternative arrangement of the injectors and the cooling air ducts; and
• 21 one of the 3 corresponding schematic representation of a seventh embodiment of an injector, in which an inner fluid channel is arranged eccentrically in an outer fluid channel.

Identical or functionally equivalent elements are provided with the same reference symbols in all figures.

one inside 1 The illustrated first embodiment of a combustion system designated as a whole by 100 comprises a fuel cell device 102 and a combustion device 104.

The fuel cell device 102 is designed in particular as a high-temperature fuel cell device 106, in particular as a solid oxide fuel cell device (SOFC).

The combustion device 104 includes a gas turbine device 108 which includes a combustor device 110 .

Furthermore, the combustion device 104 comprises a combustion chamber device 112 that is separate from the combustion chamber device 110 of the gas turbine device 108.

The gas turbine device 108 of the combustion device 104 further comprises a turbine device 114 and a compressor device 116.

The combustion system 100 also includes a fluid guide 118, by means of which fluids can be guided between the individually described devices.

The fluid guide 118 includes in particular one or more supply lines 120 for supplying fluids from the compressor device 116 to the fuel cell device 102.

Furthermore, the fluid guide 118 comprises one or more exhaust gas lines 122 for supplying exhaust gas from the fuel cell device 102 to the combustion chamber device 112.

A further exhaust gas line 124 of the fluid duct 118 serves to convey exhaust gas from the combustion chamber device 112 to the combustion chamber device 110 of the gas turbine device 108.

A further exhaust line 126 finally connects the combustion chamber device 110 of the gas turbine device 108 to the turbine device 114 of the gas turbine device 108.

The fluid guide 118 also includes a bypass line 128, by means of which exhaust gas from the fuel cell device 102 can be fed directly to the combustion chamber device 110 of the gas turbine device 108, bypassing the separate combustion chamber device 112.

The exhaust gas lines 122 for connecting the fuel cell device 102 to the separate combustion chamber device 112 are in particular an anode exhaust gas line 122a and a cathode exhaust gas line 122b.

Exhaust gas from an anode side of the fuel cell device 102 can preferably be supplied to the separate combustion chamber device 112 by means of the anode exhaust gas line 122a.

Exhaust gas from a cathode side of the fuel cell device 102 can preferably be supplied to the separate combustion chamber device 112 by means of the cathode exhaust gas line 122b.

The anode waste gas conducted in the anode waste gas line 122a preferably contains fuel.

The cathode off-gas conducted in the cathode off-gas line 122b preferably contains oxidizer.

• Mittels der Kompressorvorrichtung 116 der Gasturbinenvorrichtung 108 wird Oxidator und/oder Brennstoff verdichtet und mit einem gegenüber Normaldruck erhöhten Druck mittels der Zuführleitungen 120 der Brennstoffzellenvorrichtung 102 zugeführt.

In the 1 The first embodiment of the combustion system 100 shown works as follows:

• The oxidizer and/or fuel is compressed by means of the compressor device 116 of the gas turbine device 108 and fed to the fuel cell device 102 by means of the feed lines 120 at a pressure that is higher than normal pressure.

In the fuel cell device 102, the fuel is converted, in particular burned, to generate electricity.

The fuel flow fed to an anode side of the fuel cell device 102 preferably contains a larger quantity of fuel than can be converted during normal operation of the fuel cell device 102 .

An anode exhaust gas flow leaving the fuel cell device 102 therefore still contains fuel.

The fuel-containing anode exhaust gas flow is fed to the separate combustion chamber device 112 by means of the anode exhaust gas line 122a.

Furthermore, a cathode exhaust gas stream is supplied from the cathode side of the fuel cell device 102 to the separate combustion chamber device 112 by means of the cathode exhaust gas line 122b.

The anode waste gas and the cathode waste gas have a high temperature, for example approximately 800° C., and at least approximately the same pressure.

Mixing of the anode exhaust gas stream and the cathode exhaust gas stream with one another can therefore lead to undesired auto-ignition, for example, which could damage the combustion system 100 .

However, this can be prevented by a suitable design of the combustion device 104 (see in particular the following description of the various embodiments of the injectors).

In the combustion chamber device 112, the fuel-containing anode waste gas is burned by means of the oxidizer-containing cathode waste gas and/or by means of additionally supplied air, and the chemical energy still contained in the anode waste gas is thus used.

The hot exhaust gas from the separate combustor device 112 is fed to the combustor device 110 of the gas turbine device 108 via the exhaust pipe 124 .

Furthermore, a part of the cathode exhaust gas stream branched off from the cathode exhaust gas line 122b can be fed from the fuel cell device 102 to the combustion chamber device 110 of the gas turbine device 108 by means of the bypass line 128 , bypassing the separate combustion chamber device 112 .

In the combustor device 110 of the gas turbine device 108 , the fuel contained in the supplied fluid streams and/or additionally used fuel is combusted and used to drive the turbine device 114 of the gas turbine device 108 .

For this purpose, the exhaust gas of the combustion chamber device 110 of the gas turbine device 108 is supplied to the turbine device 114 via the exhaust gas line 126 .

However, the exhaust line 126 may also be unnecessary if the turbine device 114 connects directly to the combustor device 110 .

The exhaust gas flowing out of the combustion chamber device 110 of the gas turbine device 108 is expanded by means of the turbine device 114 in order to convert the energy contained therein into kinetic energy.

In particular, the compressor device 116 is driven by the turbine device 114 .

one inside 2 illustrated second embodiment of a combustion system 100 differs from that in 1 The first embodiment illustrated essentially in that the exhaust gas from the fuel cell device 102 is fed directly to the combustion chamber device 110 of the gas turbine device 108 by means of the exhaust gas lines 122 .

A separate combustion chamber device 112 is shown in FIG 2 illustrated second embodiment of the combustion system 100 is not provided.

In terms of structure and function, combustion chamber device 110 of gas turbine device 108 preferably corresponds to separate combustion chamber device 112 of the first specific embodiment of fuel cell system 100.

A bypass line 128 is not necessary.

Incidentally, the in 2 illustrated second embodiment of the combustion system 100 in terms of structure and function with the in 1 illustrated first embodiment match, so that reference is made to the extent to their above description.

Various embodiments of injectors and feed heads of a combustor of combustion device 104 are described below. In principle, all embodiments of injectors can be used in all embodiments of feed heads. Furthermore, all embodiments of feed heads with all embodiments of injectors are suitable for use in a combustor device 110 of the gas turbine device 108 and/or in a separate combustor device 112.

one inside 3 The illustrated first embodiment of an injector designated as a whole by 130 comprises an inner fluid channel 132, an outer fluid channel 134 and a guide channel 136.

The inner fluid channel 132 is surrounded at least in sections by the outer fluid channel 134 .

In particular, the inner fluid channel 132 and the outer fluid channel 134 are arranged coaxially to one another and have a common central axis 138, in particular a common axis of symmetry 140.

The entire injector 130 is preferably designed to be rotationally symmetrical with respect to the axis of symmetry 140 .

The inner fluid channel 132 is essentially tubular and is used to supply a first fluid to the guide channel 136 of the injector 130.

The outer fluid channel 134 is essentially in the form of a cylinder jacket and surrounds the inner fluid channel 132 . A second fluid can be supplied to the guide channel 136 of the injector 130 by means of the outer fluid channel 134 .

The first fluid routed through inner fluid channel 132, the second fluid routed through outer fluid channel 134, and the fluids routed together in guide channel 136 are directed in a flow direction 142, which is essentially parallel to central axis 138 and/or to axis of symmetry 140 of injector 130 is aligned, passed through the injector 130.

A cross-sectional area of the inner fluid channel 132 taken perpendicular to the flow direction 142 is substantially constant along the flow direction 142 .

The outer fluid channel 134 has a tapered portion 144 in which the cross-sectional area of the outer fluid channel 134 taken perpendicular to the flow direction 142 decreases along the flow direction 142 .

The tapering section 144 of the outer fluid channel 134 is arranged on an end 148 of the outer fluid channel 134 facing a combustion chamber 146 of the combustion chamber device 110 , 112 , in particular directly adjacent to the guide channel 136 .

Inner fluid channel 132 opens into guide channel 136 at an end 150 of inner fluid channel 132 facing combustion chamber 146.

An area 152, in which the inner fluid channel 132 and the outer fluid channel 134 open into the guide channel 136, is in particular an outlet area 154 of the injector 130.

In the area 152, in particular the mouth area 154, the cross-sectional area of the inner fluid channel 132, the outer fluid channel 134 and/or the guide channel 136 is minimal. The fluids guided through the injector 130 consequently have the highest flow rate in this area 152 .

The guide channel 136 of the injector 130 preferably has a constant section 156 in which a cross-sectional area of the guide channel 136 taken perpendicularly to the flow direction 142 is essentially constant along the flow direction 142 .

Guide channel 136 extends from end 150 of inner fluid channel 132 facing combustion chamber 146 and/or from end 148 of outer fluid channel 134 facing combustion chamber 146 to an end 158 of injector 130 facing combustion chamber 146.

The end 158 of the injector 130 facing the combustion chamber 146 terminates in particular flush with an exit plane 160 of a feed head 162 of the combustion chamber device 110, 112, in which the injector 130 is arranged.

The exit plane 160 is designed as a flat surface, for example, but can also be curved.

Injector 130 is used in particular to supply oxidizer and fuel to combustion chamber 146.

In particular, the first fluid conducted in the inner fluid channel 132 is an anode waste gas of the fuel cell device 102.

The second fluid conducted in the outer fluid channel 134 is, in particular, a cathode exhaust gas of the fuel cell device 102.

As an alternative to this, however, it can also be provided that the first fluid in the inner fluid channel 132 is the cathode exhaust gas and the second fluid in the outer fluid channel 134 is the anode exhaust gas.

The fluids can mix with one another at least to a small extent in the guide channel 136 of the injector 130 .

In particular when the fluids are at a high temperature, self-ignition and/or a flashback from combustion chamber 146 into injector 130 can generally occur in injector 130 .

However, this can be prevented by suitable dimensioning of the injector 130 .

This is particularly the case with the in 3 illustrated first embodiment of the injector 130 provided that the guide channel 136 has a length L, which corresponds at most approximately to the product of the mean flow rate of the fluids in the guide channel 136 and the ignition delay time of a mixture of the fluids. In this way it can be ensured that the fluids conducted in the injector 130, in particular in the guide channel 136, have already left the injector 130 before ignition occurs.

• Mittels des ersten Fluidkanals 132 wird ein erstes Fluid, beispielsweise brennstoffhaltiges Anodenabgas aus der Brennstoffzellenvorrichtung 102, zugeführt.
• Mittels des äußeren Fluidkanals 134 wird ein zweites Fluid, insbesondere oxidatorhaltiges Kathodenabgas aus der Brennstoffzellenvorrichtung 102, zugeführt.

In the 3 The first embodiment of the injector 130 shown works as follows:

• A first fluid, for example fuel-containing anode waste gas from the fuel cell device 102 , is supplied by means of the first fluid channel 132 .
• A second fluid, in particular an oxidizer-containing cathode exhaust gas from the fuel cell device 102, is supplied by means of the outer fluid channel 134.

Due to the tapering section 144 of the outer fluid channel 134 and the constant section 156 of the guide channel 136, the orifice area 154, in which the first fluid guided in the inner fluid channel 132 and the second fluid guided in the outer fluid channel 134 are combined, is a region 152 with minimal cross-sectional area. The fluids thus have the highest flow speed in this area 152 .

A recirculation of the fluids preferably only occurs in combustion chamber 146 due to the jump in area at end 158 of injector 130 facing combustion chamber 146 , and thus a stable flame front only occurs in combustion chamber 146 .

Due to the flow speed in the guide channel 136, a flashback is preferably avoided, as is self-ignition of the mixture of fluids within the guide channel 136.

Preferably, the fluids at the in 3 illustrated first embodiment of the injector 130 with essentially identical pressure to the injector 130 and finally to the guide channel 136 .

At an in 4 In the alternative mode of operation of the first embodiment of the injector 130 shown, it can be provided that one of the fluids is supplied at a pressure that is higher than the pressure of the other fluid.

For example, it can be provided that the first fluid guided in the inner fluid channel 132 is supplied at a higher pressure than the second fluid guided in the outer fluid channel 134 .

As a result, a propellant jet effect can be generated, which leads to the second fluid guided in the outer fluid channel 134 being sucked in.

Otherwise, the mode of operation corresponds to the first embodiment of the injector 130 according to FIG 4 the operation of the injector 130 as regards 3 was described.

one inside 5 illustrated second embodiment of an injector 130 differs from that in FIGS 3 and 4 illustrated first embodiment of the injector 130 essentially in that a wall 168 of the inner fluid channel 132 has at least partially roughened surfaces 164.

In particular, an inner surface 166 of the wall 168 of the inner fluid channel 132, which faces the first fluid conducted in the inner fluid channel 132, is at least partially a roughened surface 164.

In particular, it can be provided that the inner surface 166 at the end 150 of the inner fluid channel 132 facing the combustion chamber 146 is a roughened surface 146 .

Furthermore, it can be provided that an outer surface 170 of the wall 168 of the inner fluid channel 132 is a roughened surface 164 at least in sections.

In particular, it can be provided that the outer surface 170 at the end 150 of the inner fluid channel 132 facing the combustion chamber 146 is a roughened surface 164 .

A roughened surface 164 is to be understood in particular as a surface that has been machined to increase the roughness, for example a surface provided with a thread.

In addition, in one embodiment (not shown) of the injector 130 it can be provided that a surface 172 of a wall 174 surrounding the outer fluid channel 134 is a roughened surface 164 at least in sections.

Small-scale vortices can be generated by means of the roughened surface 164, which preferably serves as a microturbulator, in order to improve mixing with a relatively low pressure loss. Furthermore, this can increase boundary layer turbulence and thus minimize the risk of boundary layer separation.

Incidentally, the in 5 illustrated second embodiment of the injector 130 in terms of structure and function with in the 3 and 4 illustrated first embodiment match, so that reference is made to the extent to their above description.

one inside 6 illustrated third embodiment of an injector 130 differs from that in FIGS 3 and 4 illustrated first embodiment essentially in that the guide channel 136 comprises a widening section 176.

In the widening section 176 of the guide channel 136 , the cross-sectional area of the guide channel 136 taken perpendicularly to the flow direction 142 increases continuously and steadily along the flow direction 142 .

In particular, the widening section 176 of the guide channel 136 extends from the orifice region 154 to the end 158 of the injector 130 facing the combustion chamber 146.

An angle α, which a surface 178 of the guide channel 136 includes with the exit plane 160, is preferably greater than 90°, in particular approximately 120°.

In this way, a pressure recovery can be made possible. In particular, by deflecting the flow at the outlet of injector 130, additional mixing of the fluids in combustion chamber 146 can be generated. Adjacent injectors 130 of the delivery head 162 are preferably sized, configured, and/or positioned such that the shear layers between the fluids of adjacent injectors 130 meet.

At the in 6 illustrated third embodiment of the injector 130 can be used in particular the Coanda effect for pressure recovery.

Incidentally, the in 6 illustrated third embodiment of the injector 130 in terms of structure and function with the in the 3 and 4 illustrated first embodiment, so that reference is made to that extent to the above description.

In the 7 and 8th 1, variants of the wall 168 of the inner fluid channel 132 are shown, which can be used as a substitute for the walls 168 of the inner fluid channels 132 according to the described embodiments of the injector 130.

In 7 an embodiment is shown in which the wall 168 has a chamfer 180 .

The chamfer 180 is arranged on the end 150 of the inner fluid channel 132 facing the combustion chamber 146 in such a way that the wall 168 tapers in the direction of flow 142 towards the end 150 .

In particular, the wall 168 tapers conically.

By means of the chamfer 180, a surface discontinuity at the end 150 of the inner fluid channel 132, at which an undesired recirculation of the fluids could form, can be avoided.

At the in 8th shown embodiment, a rounding 182 of the wall 168 is provided instead of the chamfer 180. Such a rounding 182 can also prevent a jump in area to avoid recirculation zones. Furthermore, undesired detachment of the fluid flow from the wall 168 can be prevented by avoiding edges.

The rounding 182 of the wall 168 enables in particular a convex flow guidance of the fluid guided in the outer fluid channel 134 .

one inside 9 illustrated fourth embodiment of an injector 130 differs from that in FIGS 3 and 4 illustrated first embodiment essentially in that the injector 130 comprises a central fluid channel 184 in addition to the inner fluid channel 132 and the outer fluid channel 134 .

The middle fluid channel 184 is arranged between the inner fluid channel 132 and the outer fluid channel 134 .

The middle fluid channel 184 thus surrounds the inner fluid channel 132 and is itself surrounded by the outer fluid channel 134 .

The middle fluid channel 184, the inner fluid channel 132 and the outer fluid channel 134 are arranged coaxially to one another and in particular have the same axis of symmetry 140.

The middle fluid channel 184 opens into the mouth region 154, in particular into the region 152 of minimum cross-sectional area of the outer fluid channel 134 and/or the guide channel 136.

By using a further fluid channel, namely the middle fluid channel 184, a third fluid, in particular a fluid different from the first fluid and the second fluid, can be supplied to the combustion chamber 146 by means of the injector 130.

For example, it can be provided that anode waste gas is supplied from fuel cell device 102 by means of inner fluid duct 132, that cathode waste gas is supplied from fuel cell device 102 by means of central fluid duct 184, and that additional fresh air or remaining cathode waste gas is supplied from fuel cell device 102 by means of outer fluid duct 134 .

The additional fresh air or the remaining cathode exhaust gas from the fuel cell device 102 is supplied in particular in order to increase the air ratio in the combustion chamber 146 .

The fluid conducted in the outer fluid channel 134 can serve in particular to cool the wall 174 .

Alternatively, it can be provided that cathode exhaust gas is supplied from fuel cell device 102 by means of inner fluid duct 132, that anode exhaust gas is supplied from fuel cell device 102 by means of central fluid duct 184, and that additional fresh air or residual cathode exhaust gas is supplied from fuel cell device 102 by means of outer fluid duct 134 becomes.

The fuel-containing anode exhaust gas stream from the fuel cell device 102, which is supplied by means of the central fluid duct 184, is thereby surrounded by the additional fresh air or the remaining cathode exhaust gas from the fuel cell device 102, which contains oxidizer, and/or by that supplied by means of the inner fluid duct 132 Cathode exhaust flow from the fuel cell device 102 penetrated. This can improve a mixture. Furthermore, efficient cooling of the wall 174 of the outer fluid channel 134 can be made possible as a result.

Incidentally, the in 9 illustrated fourth embodiment of an injector 130 in terms of structure and function with in the 3 and 4 illustrated first embodiment match, so that reference is made to the extent to their above description.

At the in 9 The fourth embodiment shown can also have a roughened surface 164, at least in sections, in accordance with the 5 illustrated second embodiment of the injector 130 and / or a widening portion 176 of the guide channel 136 according to the in 6 illustrated third embodiment of the injector 130 may be provided.

In 10 a longitudinal section through a combustion chamber device 110, 112 is shown.

Combustion chamber device 110, 112 includes a combustion chamber wall 186 delimiting combustion chamber 146.

During operation of the combustion chamber device 110, 112, the combustion chamber wall 186 heats up considerably.

In order to cool down and thus protect the combustion chamber wall 186 , the combustion chamber device 110 , 112 has one or more cooling air ducts 188 arranged in the feed head 162 .

Cool air can flow in parallel to the combustion chamber wall 186 by means of the cooling air ducts 188 in order to avoid direct contact of the flame in the combustion chamber 146 with the combustion chamber wall 186 .

Fresh air, for example, can be used as the cooling air duct 188 . As an alternative to this, however, cathode exhaust gas from the fuel cell device 102 can also be used.

one inside 11 illustrated fifth embodiment of an injector 130 differs from that in 6 illustrated third embodiment essentially in that the guide channel 136 comprises two constant sections 156 instead of the continuously and steadily widening section 176 of the guide channel 136 .

The constant sections 156 each have constant cross-sectional areas along the direction of flow 142 .

The constant sections 156 are arranged one after the other with respect to the flow direction 142 so that an upstream constant section 156a and a downstream constant section 156b are formed.

The constant section 156a of the guide channel 136 arranged upstream adjoins the end 150 facing the combustion chamber 146 of the inner fluid channel 132 and to the end 148 of the outer fluid channel 134 facing the combustion chamber 146 .

The constant section 156b arranged downstream adjoins on the one hand the constant section 156a arranged upstream and on the other hand the exit plane 160 of the feed head 162 .

The entire guide channel 136 is thus formed by means of the constant sections 156a, 156b.

The upstream constant section 156a and the downstream constant section 156b have substantially the same axis of symmetry 140 .

A cross-sectional area of the upstream constant portion 156a is smaller than a cross-sectional area of the downstream constant portion 156b.

A transition 190 between the upstream constant portion 156a and the downstream constant portion 156b is formed as a step 192, that is, a surface discontinuity.

This results in recirculation of the fluids during operation of the injector 130 and thus reliable flame anchoring in the region of the constant section 156b arranged downstream.

one inside 12 illustrated sixth embodiment of an injector 130 differs from that in 11 Fifth embodiment illustrated essentially in that the constant section 156a arranged upstream and the constant section 156b arranged downstream do not have a common axis of symmetry 140 .

Rather, the constant section 156b arranged downstream is offset in a direction perpendicular to the direction of flow 142 with respect to the constant section 156a arranged upstream.

With such an eccentric arrangement of the constant sections 156a, 156b, flame anchoring in the constant section 156b arranged downstream can be made possible, in particular optimized.

Incidentally, the in 12 illustrated sixth embodiment of the injector 130 in terms of structure and function with the in 11 Fifth embodiment shown in accordance, so that reference is made to the above description in this respect.

one inside 13 The illustrated first embodiment of a feed head 162 includes a plurality of injectors 130 which are arranged distributed on the feed head 162 .

In particular, it can be provided that injectors 130 according to in 11 fifth embodiment shown are provided.

The injectors 130 can be uniform or, as in 13 shown, may be distributed unevenly on the feed head 162.

A non-uniform distribution of the injectors 130 results in non-uniform mixing of the fluids in the combustion chamber 146, as a result of which the reliability and/or safety of the combustion can be improved.

one inside 14 The second embodiment of a feed head 162 shown differs from that in 13 illustrated first embodiment essentially in that the injectors 130 are arranged substantially in a circle on the feed head 162.

An interior space 194 between the injectors 130 arranged in a circle is preferably selected to be large enough that a large recirculation zone can form in the combustion chamber 146 .

Incidentally, the in 14 illustrated second embodiment of the feed head 162 in terms of structure and function with the in 13 illustrated first embodiment match, so that reference is made to the extent to their above description.

one inside 15 The third embodiment of a feed head 162 shown differs from that in 13 illustrated first embodiment essentially in that the injectors 130 are arranged uniformly on the feed head 162.

However, the injectors 130 are preferably operated unevenly, which means that individual injectors 130a are charged with more fuel than the other injectors 130b.

As a result, a homogeneity of the mixture of the fluids in the combustion chamber 146 can be avoided, as a result of which the safety and reliability of the combustion can be increased.

Incidentally, the in 15 illustrated third embodiment of the feed head 162 in terms of structure and function with the in 13 illustrated first embodiment match, so that reference is made to the extent to their above description.

one in the 16 and 17 The fourth embodiment of a feed head 162 shown differs from that in 14 illustrated second embodiment essentially in that the feed head 162 has an annular cooling air duct 188 according to the in 10 illustrated embodiment of the combustion chamber device 110, 112 has.

Combustion chamber wall 186 in particular can be protected from overheating by means of cooling air duct 188 .

17 shows a longitudinal section through the feed head 162 according to FIG 16 .

Incidentally, the correct in the 16 and 17 illustrated fourth embodiment of the feed head 162 in terms of structure and function with the in 14 illustrated second embodiment, so that reference is made to the above description.

one in the 18 and 19 illustrated fifth embodiment of a feed head 162 differs from that in FIGS 16 and 17 Fourth embodiment illustrated essentially in that individual cooling air ducts 188 are provided instead of the annular cooling air duct 188 .

The cooling air ducts 188 are arranged essentially in a ring shape, in particular arranged alternating between the injectors 130 .

In particular, air at a high pressure, in particular at a higher pressure than a pressure of the fluids supplied by means of the injectors 130 , can be supplied by means of the cooling air ducts 188 . As a result, an inner recirculation zone in combustion chamber 146 can be strengthened.

A circle diameter of the circle on which the cooling air ducts 188 are arranged is preferably larger than a circle diameter of the circle on which the injectors 130 are arranged.

Incidentally, the correct in the 18 and 19 illustrated fifth embodiment of the feed head 162 in terms of structure and function with the in the 16 and 17 illustrated fourth embodiment, so that reference is made to the above description.

one inside 20 illustrated sixth embodiment of a feed head 162 differs from that in FIGS 18 and 19 fifth embodiment shown essentially in that the cooling air ducts 188 are arranged on the same circular ring as the injectors 130.

Incidentally, the in 20 illustrated sixth embodiment of the feed head 162 in terms of structure and function with the in the 18 and 19 Fifth embodiment shown in accordance, so that reference is made to the above description in this respect.

one inside 21 illustrated seventh embodiment of an injector 130 differs from that in FIGS 3 and 4 illustrated first embodiment essentially in that the inner fluid channel 132 and the outer fluid channel 134 have no common axis of symmetry 140.

Rather, the inner fluid channel 132 is offset eccentrically in the outer fluid channel 134 . An axis of symmetry 140a of the inner fluid channel 132 is thus arranged offset parallel to an axis of symmetry 140b of the outer fluid channel 132 .

Such an offset arrangement can, for example, produce a shear layer that is richer in fuel on one side for optimized combustion.

Incidentally, the in 21 shown seventh embodiment of an injector 130 in terms of structure and function with the in the 3 and 4 illustrated first embodiment match, so that reference is made to the extent to their above description.

In principle, individual or multiple features of the described embodiments of combustion systems 100, injectors 130 and/or feed heads 162 can be combined with one another as desired to provide further preferred embodiments.

For example, it can be provided that the feed head 162 according to the in 15 illustrated third embodiment with injectors 130 according to the in 6 illustrated third embodiment in a combustion system 100 according to FIG 1 illustrated first embodiment, in particular in the separate combustion chamber device 112 or in the combustion chamber device 110 of the gas turbine device 108 is used.

Reference List

100

combustion system

102

fuel cell device

104

combustion device

106

High temperature fuel cell device

108

gas turbine device

110

Combustion chamber device of the gas turbine device 108

112

Combustion chamber device of a separate combustion device 104

114

turbine device

116

compressor device

118

fluid guidance

120

supply line

122

exhaust pipe

122a

anode exhaust line

122b

Cathode exhaust line

124

exhaust pipe

126

exhaust pipe

128

bypass line

130

injector

130a

injector

130b

injector

132

internal fluid channel

134

outer fluid channel

136

guide channel

138

central axis

140

axis of symmetry

140a

Axis of symmetry of the inner fluid channel 132

140b

Axis of symmetry of the outer fluid channel 134

142

flow direction

144

tapered section of outer fluid channel 134

146

combustion chamber

148

the end of the outer fluid channel 134 facing the combustion chamber 146

150

the end of the inner fluid channel 132 facing the combustion chamber 146

152

Area of minimum cross-sectional area

154

mouth area

156

constant section of the guide channel 136

156a

upstream constant section

156b

downstream constant section

158

end of injector 130 facing combustion chamber 146

160

exit level

162

feeding head

164

roughened surface

166

inner surface

168

Wall of the inner fluid channel 132

170

outer surface

172

Surface of the wall 174 of the outer fluid channel 134

174

Wall of the outer fluid channel 134

176

expanding section of the guide channel 136

178

surface

180

chamfering

182

rounding off

184

middle fluid channel

186

combustion chamber wall

188

cooling air duct

190

crossing

192

Step

194

inner space

a

angle

L

Length of the guide channel 136

Claims (16)

Method for operating a combustion system (100), wherein the combustion system (100) comprises a fuel cell device (102) designed, for example, as a high-temperature fuel cell device (106) and a combustion device (104) for burning fuel-containing exhaust gas from the fuel cell device (102), the method The following comprises: - supplying fuel to the fuel cell device (102); - Discharge of exhaust gas from the fuel cell device (102) which comprises fuel and is preferably at an elevated pressure relative to atmospheric pressure; - Supplying the exhaust gas from the fuel cell device (102) as one of at least two fluids to a combustion chamber (146) of a combustion chamber device (110, 112) of the combustion device (104) using an injector (130), the injector (130) having an inner Fluid duct (132), an outer fluid duct (134) surrounding the inner fluid duct (132) at least in sections, and a guide duct (136), a first fluid being ducted by means of the inner fluid duct (132) and a second fluid being ducted by means of the outer fluid duct (134). are fed coaxially to the guide channel (136) with at least approximately the same flow rate, a supply pressure of the first fluid at least approximately corresponding to a supply pressure of the second fluid. procedure after claim 1 , characterized in that using the injector (130) an oxidizer is supplied as a further fluid of the at least two fluids to the combustion chamber (146) of the combustion chamber device (110, 112), wherein a pressure of the oxidizer before its supply to the injector ( 130) by means of a compressor device (116) of a gas turbine device (108) of the combustion device (104) is increased such that the pressure corresponds at least approximately to the pressure of the exhaust gas from the fuel cell device (102). Procedure according to one of Claims 1 or 2 , characterized in that the combustion device (104) comprises a plurality of injectors (130), by means of which the combustion chamber (146) are supplied with the at least two fluids, the injectors (130) being supplied with fluid flows having different volume flows and/or mass flows. Procedure according to one of Claims 1 until 3 , characterized in that as one of the at least two fluids, a partial stream of a total anode exhaust stream from the fuel cell device (102) of the combustion device (104) is supplied. Procedure according to one of Claims 1 until 4 , characterized in that as one of the at least two fluids, a partial stream of a total cathode exhaust stream from the fuel cell device (102) of the combustion device (104) is supplied. Procedure according to one of Claims 1 until 5 , characterized in that as one of the at least two fluids anode exhaust gas from the fuel cell device (102) and as another of the at least two fluids cathode exhaust gas from the fuel cell device (102) of the combustion device (104) is supplied. procedure after claim 6 , characterized in that only two fluids are supplied, as one of the two fluids exclusively anode exhaust gas from the fuel cell device (102) and as another of the two fluids exclusively cathode exhaust gas from the fuel cell device (102) is supplied. Procedure according to one of Claims 6 or 7 , characterized in that the at least two fluids are supplied from the fuel cell device (102) to the guide channel (136) in such a way that the at least two fluids between the fuel cell device (102) and the guide channel (136) have at least approximately the same total pressure loss. Procedure according to one of Claims 1 until 8th , characterized in that the at least two fluids with at least approximately identical pressure of the combustion device (104) are supplied. Procedure according to one of Claims 1 until 9 , characterized in that a fluid which is supplied as one of at least two fluids is or comprises ambient air from an environment of the combustion system. Combustion system (100), comprising a fuel cell device (102) designed, for example, as a high-temperature fuel cell device (106), and a combustion device (104) for burning fuel-containing exhaust gas from the fuel cell device (102), the combustion device (104) comprising the following: - a combustion chamber device ( 110, 112) comprising a combustion chamber (146), and - an injector (130) for supplying fuel and oxidizer to the combustion chamber (146), the injector (130) having an inner fluid channel (132), a the inner fluid channel (132) surrounding the outer fluid duct (134) at least in sections and a guide duct (136) which is arranged downstream of the inner fluid duct (132) with respect to a flow direction (142) and which opens into the combustion chamber (146), an anode exhaust gas line (122a) of the fuel cell device (102) and/or a cathode exhaust gas line (122b) of the fuel cell device (102) is fluidically connected to the injector (130), so that by means of at least one fluid channel (132, 134, 184) of the injector (130) an anode -Exhaust stream and / or a cathode exhaust stream of Fuel cell device (102) can be fed to the combustion chamber (146), a first fluid being able to be fed to the guide channel (136) by means of the inner fluid channel (132) and a second fluid by means of the outer fluid channel (134) coaxially with at least approximately the same flow rate, wherein a Supply pressure of the first fluid corresponds at least approximately to a supply pressure of the second fluid. Combustion system (100) according to claim 11 , characterized in that the anode exhaust gas line (122a) of the fuel cell device (102) with a first fluid channel (132, 134, 184) of the injector (130) and the cathode exhaust gas line (122b) of the fuel cell device (102) with a second fluid channel (132, 134, 184) of the injector (130) is fluidically connected, so that the anode exhaust gas flow and the cathode exhaust gas flow can be combined by means of the injector (130) and the combustion chamber (146) can be fed. Combustion system (100) according to any one of Claims 11 or 12 , characterized in that the combustion system (100) comprises a fluid duct (118) by means of which a fluid stream, which preferably has a pressure that is higher than atmospheric pressure, - can be fed to the fuel cell device (102) as a fuel stream with excess fuel, - then at least partially as a fuel stream can be fed to the combustion chamber (146) by means of the injector (130) and - can then be expanded via a turbine device (114) of a gas turbine device (108) of the combustion device (104). Combustion system (100) according to any one of Claims 11 until 13 , characterized in that the combustion device (104) comprises a gas turbine device (108) and that the combustor device (110) is a combustor device (110) of the gas turbine device (108). Combustion system (100) according to any one of Claims 11 until 14 , characterized in that at least one section (156a) of the guide channel (136), in particular the entire guide channel (136), has a length (L) which is at most approximately the product of the mean flow velocity of the fluids in this section (156a) or in the entire guide channel (136) and corresponds to the ignition delay time of a mixture of the fluids. Combustion system (100) according to any one of Claims 11 until 15 , characterized in that the combustion system (100) comprises a compressor device (116), by means of which a supply pressure of a fluid to be supplied to the combustion chamber (146) by means of the injector (130) is matched to a supply pressure of a fluid which is discharged from the fuel cell device (102) and also discharged by means of the Injector (130) the combustion chamber (146) supplied fluid adjustable, in particular adjustable, is.

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