Combustion system and method

Abstract

A system is disclosed that includes a gas turbine engine fuel injector configured to deliver a first injection fluid including a first fuel and a second injection fluid including a second fuel to a combustion chamber of the gas turbine engine. The apparatus is configured to deliver the first injection fluid and the second injection fluid such that the first injection fluid is delivered in a first flow and the second injection fluid is delivered in a second flow. Further, both the first flow and the second flow are delivered such that a delivery zone exists corresponding to an initial location where the first flow is substantially radially surrounded by the second flow.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to combustor systems and methods. Aspects of the present invention relate to a system comprising a fuel injection device, a gas turbine engine, a method of injecting fuel into a gas turbine engine, and a gas turbine engine fluid system. The present disclosure may be applicable, in particular but not exclusively, to combustors configured to be at least partially fueled by ammonia fuel. The present disclosure may be particularly applicable to combustors used in gas turbine engines or boilers for use in the field of power generation, but is also relevant to other fields (for example, marine, aerospace, and railway applications).

BACKGROUND ART

[0002] This background art section is provided in relation to ammonia-fueled gas turbine engines, but this is merely for convenience, and it will be understood that the disclosed technology may be applied to alternative systems.

[0003] In relation to environmental impact, the use of ammonia as a fuel (for example, in gas turbine engines) has potential advantages compared to carbon-based fuels such as kerosene and fuel oil. Specifically, ammonia combustion with air produces nitrogen and water, rather than carbon dioxide and water.

SUMMARY OF THE INVENTION

PROBLEMS TO BE SOLVED BY THE INVENTION

[0004] Nevertheless, ammonia presents other challenges. The combustion of ammonia in air produces nitrogen oxides (undesirable emission products), and ammonia hardly burns in air. The latter problem can be overcome by using an additional fuel, such as hydrogen, to help ignite the ammonia. However, this can amplify nitrogen oxide production, as hydrogen can burn in high-temperature air, producing nitrogen oxides and water. Storing a second fuel, such as hydrogen, also presents further complexities and risks. [Means for solving the problem]

[0005] A system is provided which optionally comprises a gas turbine engine fuel injector optionally configured to deliver a first injector optionally containing a first fuel and a second injector optionally containing a second fuel to the combustion chamber of a gas turbine engine, wherein the injector optionally configured to deliver the first injector and the second injector such that the first injector is delivered in a first flow and the second injector is delivered in a second flow, and optionally both the first and second flows are delivered, and optionally there exists a delivery zone corresponding to the first location where the first flow is substantially radially surrounded by the second flow.

[0006] For example, when different fuels offer different performance and / or characteristics, it may be desirable to use multiple different fuels for combustion. For instance, one fuel may offer better efficiency, easier or safer storage, be more readily available, and / or produce fewer types or amounts of pollutants, but may be more difficult to burn than another fuel. Therefore, the latter, more easily combustible fuel may be burned to bring the temperature sufficient to ignite the less combustible fuel. Thus, benefits can be obtained by burning fuels in such combinations.

[0007] By delivering the injection fluid, and therefore the fuel, in a stratified state as described above, the reactions of the delivered species in the injection fluid can be made to occur at different rates and / or temperatures, allowing for control over the integrity of combustion, the reactions that occur, and / or the composition of the emissions. For example, reaction products from the higher temperature combustion of the first fuel in the first flow (occurring near the flame core) can further react with unburned second fuel in the second flow, thereby removing undesirable combustion products and reducing undesirable emissions. The availability of unburned second fuel for this purpose can be increased as a result of the second flow being positioned radially outward from the first flow and away from the higher temperature core of the flame, potentially resulting in less burning in the second flow. As a further example, the presence of a second flow surrounding the first flow may mean that the reaction products from the combustion of the first fuel are at least partially constrained by the second fuel surrounding the second flow and are more likely to react with the second fuel surrounding the second flow. As a further example, the first flow (radially inward) may tend to follow a more direct path through the associated combustor than the second flow (radially outward), which may be more likely to be recirculated within the combustor. This can be advantageous when it is desirable that a significant proportion of the first fuel be burned at a lower temperature in one or more downstream combustion processes. Furthermore, by injecting the injection fluid, and therefore ultimately the fuel, in separate flows rather than a mixed flow, for example, more precise fuel metering can be achieved, allowing for better control of the ignition stage and the combustion process.

[0008] In some embodiments, the apparatus is configured to deliver a first flow and a second flow in substantially the same direction. This direction may be, for example, axial with respect to a combustor configured to house a fuel injector and / or a gas turbine engine configured to house a fuel injector. This facilitates the delivery of the first and second flows in close proximity, with the first flow surrounded by the second flow. The common direction may also facilitate specific flow characteristics in the delivery zone and downstream thereof.

[0009] In some embodiments, the first and second flows are delivered from separate, corresponding first and second outlets. The second outlet may substantially surround or directly surround the first outlet. Additionally or alternatively, the outlets may be adjacent.

[0010] In some embodiments, the first outlet is angled with respect to the radiating plane so as to guide the first injection fluid flow into the second injection fluid flow. Thus, the first outlet can be angled with respect to both the radiating plane and the axial plane. An angled nozzle can deliver the first fuel of the first injection fluid for stoichiometric combustion and thus increase the temperature. Additionally, there may be a tendency to bend and deflect the flame from the axial direction, which may be advantageous with respect to the recirculation of reactants in the combustion chamber.

[0011] In some embodiments, the first outlet and the second outlet are substantially concentric. In this way, a uniform flow of the first and / or second injection fluid can be obtained regardless of the angular direction.

[0012] In some embodiments, the first outlet has an annular cross-section. This may allow for the placement of at least one additional outlet radially inward from the first outlet to deliver additional fluid to the delivery zone and / or combustion chamber.

[0013] In some embodiments, the second outlet has an annular cross-section. This makes it easier to position the first outlet radially inward of the second outlet and surrounded by the second outlet.

[0014] In some embodiments, the system is configured to deliver air for combustion with the first and second fuels after delivery, and includes an air outlet located radially inward from the first outlet and radially surrounded by the first outlet. The air outlet may have a circular cross-section.

[0015] In some embodiments, the first outlet and the air outlet may be provided on the burner head.

[0016] Each of the aforementioned outlets may be axially aligned with one or both of the other outlets, or it may be axially offset from one or both of the other outlets. Each outlet may be continuous or may consist of multiple separate openings.

[0017] In some embodiments, the apparatus includes a first passage through which a first injection fluid is delivered to a first outlet. The first passage may have an annular cross-section.

[0018] In some embodiments, the apparatus includes a second passage located radially outside the first passage and surrounding the first passage radially, through which a second injection fluid is delivered to a second outlet. The second passage may have an annular cross-section.

[0019] In some embodiments, the second passage includes an angular swirl configured to provide a tangential swirl to the second injection fluid for its delivery from the second outlet. This swirl can enable improved control over the mixing and interaction of the first and second flows, and can provide control over the reaction rate between the chemical components of the first and second flows, and thus potentially over the discharge composition.

[0020] In some embodiments, the system includes an auxiliary fuel outlet located in a second passage configured to deliver auxiliary fuel to the remainder of the second injection fluid before it is delivered to the combustion chamber by the device. This can enhance the mixing of the auxiliary fuel with the remainder of the second injection fluid. The auxiliary fuel outlet may be located downstream of the angle swahl so as to help prevent flashback of the auxiliary fuel. The auxiliary fuel may be a reactant having a higher reaction rate than the second fuel, such as hydrogen gas and / or methane gas, which can help the combustion of the second fuel in the combustion chamber.

[0021] In some embodiments, the system includes an auxiliary fuel passage through which auxiliary fuel is delivered to an auxiliary fuel outlet. The auxiliary fuel passage may be located between a first passage and a second passage.

[0022] In some embodiments, the system includes a heating fluid chamber configured such that the heating fluid in the heating fluid chamber is in thermal contact with the second injection fluid in the second passage in order to control the temperature of the second injection fluid. The thermal energy of the heating fluid may be generated by the combustion of the first and second fuels in the combustion chamber. The heating fluid may be, for example, water and / or steam.

[0023] In some embodiments, the system includes an air passage located radially inside the first passage and radially surrounded by the first passage, through which air is delivered to an air outlet. The air passage may have a circular cross-section.

[0024] In some embodiments, the air passage includes an axial swirler configured to impart an axial swirl to the air for delivery from an air outlet. The axial swirl of the air delivered from the air outlet can help stabilize a small central flame within the delivery zone that combusts at least a portion of a first injected fluid, for example a first fuel. In addition, swirling the ignited first fuel of the first injected fluid can generate recirculation in the delivery zone and / or in the vicinity of the delivery zone, resulting in recirculation in the vicinity of the delivery zone via vortex breakdown. This can increase the residence time of the first fuel in the vicinity of the delivery zone and enhance the completeness of its combustion here (e.g., rather than in a later stage), which can have a beneficial effect with respect to the potential reduction of products of this combustion process due to reaction with unburned components of the second injected fluid.

[0025] In some embodiments, initial combustion of at least a portion of the first injected fluid in the first stream acts as a pilot for ignition of at least a portion of the second injected fluid in the second stream.

[0026] In some embodiments, one of the first fuel and the second fuel comprises a slow-reacting fuel, and the other comprises a fast-reacting fuel. The slow-reacting fuel may be a fuel that does not burn readily in air compared to the fast-reacting fuel, and / or burns in air only under a significantly reduced range of conditions (e.g., temperature). Under at least some of the conditions prevailing in the combustion chamber without the presence of the fast-reacting fuel, the slow-reacting fuel may be of a type that does not combust. Accordingly, the presence and properties of the fast-reacting fuel may enable combustion of the slow-reacting fuel. The difference in reaction rates between the first fuel and the second fuel may be attributed to the chemical composition of the respective fuels, that is, the first fuel and the second fuel have different chemical compositions (e.g., rather than different phases of the respective fuels). The slow-reacting fuel may be, for example, ammonia gas, and / or the fast-reacting fuel may be, for example, hydrogen gas and / or methane gas.

[0027] In some embodiments, the first fuel comprises a fast-reacting fuel and the second fuel comprises a slow-reacting fuel. This combination can complement the system architecture. Specifically, the slow-reacting fuel in the second flow radially outward may be partially separated from the hot core of the combustion flame, which may mean that a significant proportion of the slow-reacting fuel may remain unburned. With sufficient recirculation, at least within the combustor, this unburned slow-reacting fuel may react with undesirable combustion products from the overall combustion process occurring near the center of the combustion flame. Furthermore, the delivery of the slow-reacting fuel in a flow surrounding the flow of the fast-reacting fuel tends to capture combustion products from the combustion of the fast-reacting fuel, increasing the reaction of those products with the fast-reacting fuel. For example, if the fast-reacting fuel is hydrogen gas and the slow-reacting fuel is ammonia gas or an ammonia blend, the central combustion of hydrogen may produce NOx, which is undesirable in emissions. However, NOx can react with unburned ammonia, formed radicals, and / or other species surrounding them, and / or be recirculated together to produce nitrogen gas and vapor. Furthermore, NOx produced by the combustion of ammonia can also be reduced by surrounding radicals at the contact point between the first and second injection fluids. Moreover, fast-reacting fuels delivered in the central flow, such as hydrogen, may tend to follow more direct paths to any downstream region of the combustion process (i.e., less likely to be recirculated than the surrounding layer containing slower-reacting fuels). For example, if this includes a flameless combustion zone, it may be desirable to deliver a significant proportion of the fast-reacting fuel as directly as possible to this combustion zone, where combustion conditions are less likely to produce undesirable emissions.

[0028] In some embodiments, the second fuel further comprises a fast-reacting fuel that can serve as an auxiliary fuel. This may be the same as the fast-reacting fuel in the first fuel. Providing a fast-reacting fuel in the second fuel can help the combustion of the slow-reacting fuel in the combustion chamber.

[0029] In some embodiments, the second injection fluid additionally comprises one or more other components. These other components may be provided, for example, for use in combustion (e.g., air), to react with combustion products, and / or to increase the mass of a fluid in the combustor, such as steam, and / or to control the rate of combustion and / or reaction.

[0030] In some embodiments, the delivery zone is radially surrounded and defined by a Coanda generator.

[0031] In some embodiments, the Coanda generator comprises a tubular portion that radially surrounds the apparatus, the tubular portion having a radially inner surface of constant cross-section, and a flared portion connected to the radially inner surface downstream of the tubular portion. The tubular portion may be substantially cylindrical. The Coanda generator (and particularly the tubular portion) can help protect the initial flame and the onset of combustion from turbulence. The Coanda generator (and particularly the flared portion) can help provide an initial direction to the first flow and the second flow to facilitate the generation of recirculating flow within the combustor.

[0032] In some embodiments, the flared portion has a radial inner surface with a cross-section that progressively widens downstream and comprises a continuous tapered portion connected to the tubular portion. This can generate a low-pressure region that tends to bend the initial flow from the device to have a larger component in the radially outward direction. Thus, the flame is thought to be flattened. This tends to cause the initial flow to eventually reach the sidewalls of the combustion chamber, and as a result, the flow may be redirected so that some of it moves downstream and some moves upstream. The downstream portion may eventually be partially recirculated by being redirected further and moving downward towards the center of the combustion chamber. The upstream portion may form a vortex surrounding the Coanda generator and tend to be trapped in the vortex. Recirculation can increase residence time and potentially increase the integrity of combustion and / or the opportunity for undesirable combustion products to react further. Recirculation can also lower the combustion temperature, in particular by controlling the temperature produced by a heat transfer process involving another fluid, e.g., steam, which is desirable and can help with flameless combustion. Flame flattening also helps guide the flame away from the burner head, thereby reducing burner head damage over time and potentially lowering maintenance requirements.

[0033] In some embodiments, the radial inner surface of the tubular portion and the radial inner surface of the continuous tapered portion intersect at a discontinuity in the form of an edge. This can help generate a small toroidal region of low pressure downstream of the edge.

[0034] In some embodiments, the flared portion has a substantially radially extending downstream surface and comprises a rim portion connected to a continuous tapered portion. The rim portion can generate a further low-pressure region that further bends the initial flow from the apparatus, having a larger component in the radially outward direction. This can thus assist in generating the recirculation process described above.

[0035] In some embodiments, the radial inner surface of the continuous tapered portion and the downstream surface of the rim portion intersect at a discontinuity in the form of an edge. This can help generate a small toroidal region of low pressure downstream of the edge.

[0036] In some embodiments, the Coanda generator extends into a combustion chamber defined by the combustor can, forming a vortex region radially bounded by the radially outer surface of the Coanda generator and the radially inner surface of the combustor can, and axially bounded by the upstream surface of the combustor can. This vortex region can be considered a vortex stagnation region. A fluid delivered by the device and moving with a radially outward component can reach the side walls of the combustor can and be partially directed upstream. The flow can then be redirected again, first by the upstream wall of the combustor can and then by the radially outer surface of the Coanda generator. This flow may have a tendency to form a vortex in the vortex region. The vortex region may be configured to facilitate vortex formation. Thus, for example, the aforementioned walls and surfaces may not be at least substantially interrupted and / or continuous. Furthermore, injection of other materials, such as fuel or air, within the vortex region may be omitted so as not to hinder vortex formation. In the system, only fuel can be injected through the first and second flows. The vortex can increase its residence time at a controllable temperature. Furthermore, vortices may increase the chances of further reactions of combustion integrity and / or undesirable combustion products. As understood, the combustor can may be substantially cylindrical.

[0037] In some embodiments, the upstream wall of the combustor can has a configuration that increases the surface area of ​​the upstream wall compared to a flat configuration. The upstream wall may include structures such as undulations (e.g., corrugations, castellations, channels, or peaks and troughs) or fins in its structure. This can facilitate increased heat energy transfer between the fluid in the combustion chamber and the fluid in the heating fluid chamber, provided that the heating fluid chamber is properly positioned (e.g., adjacent to and / or in thermal contact with the upstream wall of the combustor can). It should be noted that the heating fluid chamber can be positioned in this manner regardless of the configuration of the upstream wall of the combustor can. Heat transfer between the heating fluid in the heating fluid chamber and the fluid in the combustion chamber can serve to cool the fluid in the combustion chamber, particularly in vortex regions. This can aid in further reactions of combustion products, which may themselves be undesirable as emissions. This configuration can additionally or alternatively increase the strength of the upstream wall for a given weight of material.

[0038] In some embodiments, the upstream surface of the combustor can may include undulations. The undulations may be configured such that each peak and trough of each undulation extends radially. The undulations may be provided in a repeating pattern or irregular. Such undulations may further aid in the formation of vortices in the fluid within the vortex region. As understood, the undulations may be formed, and / or actually formed, by structures that increase the surface area as described above.

[0039] In some embodiments, the upstream surface of the combustor can be inclined and / or sloped with respect to the radial direction such that the upstream surface moves further downstream from the radially outward to the radially inward direction. If the upstream surface is inclined, it may form an angle of about 15 to about 60 degrees with respect to the radiating surface.

[0040] In some embodiments, water and / or steam may be injected into the vortex region through one or more ports on the upstream wall of the combustor canister. The steam thus injected may help to lower the temperature of the fluid in the vortex region, in particular, and may aid in the further reaction of combustion products, which may themselves be undesirable as emissions. The ports may be configured to inject water and / or steam in a direction substantially perpendicular to the upstream surface of the combustor canister at the location of the port. This may help to form a vortex in the fluid in the vortex region.

[0041] In some embodiments, the outer surface of the Coanda generator has a substantially concave shape. The radial outer surface may be substantially parallel to the extent that it is provided, for example, at positions corresponding to the radial inner surface of the tubular portion, the radial inner surface of the continuous tapered portion, and / or the downstream surface of the rim portion. In this way, the outer surface of the Coanda generator can facilitate the formation of vortices within the vortex region by an incident fluid flow that is appropriately redirected.

[0042] In some embodiments, the combustor can may have a waist that is tapered such that its radial inner surface is narrowed in diameter, and the waist is positioned such that, with respect to its position along the combustor can, substantially intersects a fluid flow that moves downstream from the assembly and is redirected by the Coanda generator to increase its component in the direction toward the radial inner wall of the combustor can. The waist may have a tendency to facilitate the redirection of the flow from the assembly at the sidewall of the combustor can into a flow that moves downstream and is eventually recirculated, and a flow that moves upstream and is eventually vortex-forming.

[0043] In some embodiments, the combustion chamber comprises a primary combustion zone located downstream of the apparatus where rich combustion occurs, and a secondary combustion zone located downstream of the primary combustion zone where flameless combustion occurs. The secondary combustion zone may be located immediately downstream of the primary combustion zone. Compared to the primary combustion zone, the secondary combustion zone may have higher humidity levels in combustion products and / or other reaction products and / or further fluid components and / or higher fuel dilution. In the secondary combustion zone, combustion may occur at temperatures substantially below 1300K. Due to the lower temperature, flameless combustion can help reduce undesirable emission products and the generation of traces from rich combustion of a second fuel, especially when burning a fast-reacting fuel such as hydrogen, which may be the first fuel.

[0044] In some embodiments, the combustor can may have at least one air inlet within or adjacent to the secondary combustion zone, the at least one air inlet configured to deliver additional air to the combustion chamber. The at least one air inlet may be located close to the beginning of the secondary combustion zone. The at least one air inlet may be configured to generate an axial-tangential swirl, which can promote mixing and residence time for more complete combustion and enhance stability. This air delivery can facilitate the dilution of the first and second fuels present in the secondary combustion zone, enabling combustion in a less noticeable mode and potentially facilitating flameless combustion.

[0045] In some embodiments, the combustor can may be provided with at least one nitrogen inlet in or adjacent to the secondary combustion zone, the at least one nitrogen inlet configured to deliver nitrogen to the combustion chamber. The at least one nitrogen inlet may be located close to the beginning of the secondary combustion zone. The at least one nitrogen inlet may be configured to generate an axial-tangential swirl, which can promote mixing and residence time for more complete combustion and increase stability. Such nitrogen injection can reduce reactivity and temperature in the secondary combustion zone, further promoting the correct conditions for flameless combustion and / or causing more stable expansion in the turbine downstream of the combustor. The delivered nitrogen may be supplied from a cracker located in the combustion chamber (further described below).

[0046] As can be understood, at least one air inlet and at least one nitrogen inlet may be a combined air and nitrogen inlet.

[0047] In some embodiments, the combustion chamber includes a baffle between the primary and secondary combustion zones, which reduces the cross-sectional area of ​​the combustion chamber and thereby creates a flow constriction for the fluid passing from the primary to the secondary combustion zone. The baffle may be substantially centrally located radially within the combustion chamber and define a passage between the primary and secondary combustion zones around the baffle. The passage may be, for example, annular. The baffle may have an upstream-facing projection that may have a central apex. The baffle may be, for example, dome-shaped, conical, truncated cone-shaped, oval-shaped, or spherical. The baffle may help to form recirculation within the primary combustion zone. Specifically, the baffle may help to swirl a flow moving downstream toward the radial end of the combustion chamber so that it moves upstream closer to the center of the combustion chamber.

[0048] In some embodiments, a cracker is placed in a combustion chamber configured to provide thermal contact between the combustion fluid in the combustion chamber and a first cracker fluid that passes through a first channel in the cracker, thereby undergoing a first process that chemically decomposes the first cracker fluid into two or more chemical species. By placing the cracker in the combustion chamber, the heat necessary for decomposition can be generated within the cracker. The decomposition products may be useful, in particular, for generating one or more species of components of a first injector fluid and / or a second injector fluid, such as a first fuel and / or other fluids used in the system. For example, the first cracker fluid may be ammonia, which can be decomposed into nitrogen and hydrogen within the cracker. The hydrogen may be a first fuel, and the nitrogen may be delivered to the combustion chamber of a secondary combustion zone. The cracker can act as a baffle.

[0049] In some embodiments, one of the chemical species is the first fuel. The first fuel of the first injection fluid may be delivered from the cracker through the outlet of the first channel and may be separated from one or more other chemical species in an intermediate stage (e.g., a molecular sieve). The molecular sieve may be suitable for separating hydrogen and nitrogen gases decomposed from ammonia in the cracker.

[0050] In some embodiments, the other chemical species is nitrogen. This nitrogen may be delivered to the nitrogen inlet of the combustor can.

[0051] In some embodiments, the cracker is further configured to provide thermal contact between the combustion fluid in the combustion chamber and a second cracker fluid that passes through a second channel in the cracker and undergoes a second process that increases the thermal energy of the second cracker fluid without changing or substantially changing its chemical properties. It may be desirable for the temperature of the second cracker fluid to rise. The second cracker fluid may be, for example, one of the first and second fuels, and as its temperature rises, it can burn more easily and / or with greater efficiency. Additionally or alternatively, the second cracker fluid can cool the cracker.

[0052] In some embodiments, the first cracker fluid and the second cracker fluid have the same composition. The fluids may originate from the same reservoir.

[0053] In some embodiments, the second cracker fluid is a second fuel. The second fuel of the second injection fluid may exit the cracker through the outlet of the second channel. The second cracker fluid may be, for example, ammonia.

[0054] In some embodiments, the first and second channels are positioned within the cracker such that the first cracker fluid receives more heat from the combustion chamber fluid than the second cracker fluid. This can be achieved, for example, by positioning the first channel near the high-temperature side of the cracker (e.g., the side facing the primary combustion zone) and the second channel near the low-temperature side of the cracker (e.g., the side facing the secondary combustion zone), or by using materials with different thermal conductivity properties for the different passages. The resulting difference can facilitate different desired heating levels (e.g., heating levels that result in chemical decomposition of the first cracker fluid and simple heating of the second cracker fluid).

[0055] In some embodiments, the system includes a fuel heat exchanger configured to bring into thermal contact at least a portion of the airflow moving into the compressor of a gas turbine engine with a flow of a second fuel moving by the device for delivery in a second injection fluid. This can lower the temperature of the airflow moving into the compressor via refrigeration. Furthermore, in this manner, the second fuel may be heated before combustion, thereby improving efficiency and / or causing a change of state of the second fuel from a desired storage state (e.g., liquid) to a desired combustion state (e.g., gas). This can be completed before further heating and / or decomposition of the second fuel in the cracker. In addition, the mass of air entering the compressor is increased by its cooling, and therefore the efficiency is potentially higher.

[0056] In some embodiments, the system includes an exhaust fluid heat exchanger configured to bring into thermal contact at least a portion of the exhaust fluid flow from a gas turbine engine with a flow of water moving for delivery to the apparatus and / or combustion chamber. The water may, for example, be converted to steam as a result of passing through the exhaust fluid heat exchanger, and / or delivered as part of a second injection fluid to increase its mass in the combustor, and / or introduced into the combustion chamber via one or more alternative means, for example, one or more alternative ports (dedicated or non-dedicated) in the primary and / or secondary combustion zones. Additionally or alternatively, at least a portion of the steam may be used to preheat the second injection fluid via heat exchange (e.g., via heat exchange in the apparatus) before delivery of the second injection fluid by the apparatus. Additionally or alternatively, particularly if there is an excess of water / steam, the excess water / steam may be used for district heating and / or agriculture.

[0057] In some embodiments, the system includes a condenser configured to cool at least a portion of the exhaust fluid flow from a gas turbine engine and separate water from at least a portion of the exhaust fluid flow. The water may be converted from vapor to liquid water by the condenser, for example, and the condenser can separate water from one or more remaining exhaust fluid components that remain in gaseous form. The exhaust fluid may also contain nitrogen gas, which can be discharged into the atmosphere once separated from water by the condensation process.

[0058] In some embodiments, the water flow that moves for delivery to the apparatus and / or combustion chamber is water produced by a condenser. Additionally or alternatively, at least a portion of the water produced by the condenser may be used to cool the apparatus.

[0059] According to a second aspect of the present invention, a gas turbine engine comprising the system of the first aspect is provided.

[0060] A third aspect of the present invention provides a method for injecting fuel in a gas turbine engine, which optionally includes the step of delivering a first injection fluid optionally containing a first fuel and a second injection fluid optionally containing a second fuel to a combustion chamber, optionally such that the first injection fluid is delivered in a first flow and the second injection fluid is delivered in a second flow, and optionally both the first and second flows are delivered, and there exists a delivery zone corresponding to the first location where the first flow is substantially radially surrounded by the second flow.

[0061] In some embodiments, the method includes the steps of burning at least a portion of the first fuel and / or the second fuel in an initial rich combustion process, and then burning at least a portion of the first fuel and / or the second fuel in a flameless combustion process.

[0062] In some embodiments, the method includes performing a first process, which involves heating a first cracker fluid using heat generated by the combustion of a first fuel and / or a second fuel to chemically decompose the first cracker fluid into two or more chemical species.

[0063] In some embodiments, one of the chemical species is the first fuel.

[0064] In some embodiments, the other chemical species is nitrogen.

[0065] In some embodiments, the method includes the step of performing a second process, which involves heating a second cracker fluid using heat generated by the combustion of a first fuel and / or a second fuel, thereby increasing the thermal energy of the second cracker fluid without altering its chemical properties.

[0066] In some embodiments, the first cracker fluid and the second cracker fluid have the same composition.

[0067] In some embodiments, the method includes the step of bringing at least a portion of the airflow moving into the compressor of a gas turbine engine into thermal contact with a flow of a second fuel moving to be delivered into a second injection fluid.

[0068] In some embodiments, the method includes the step of bringing at least a portion of the exhaust fluid flow from a gas turbine engine into thermal contact with a water flow that moves to be delivered to the combustion chamber and / or to preheat the second injection fluid by heat exchange before delivery of the second injection fluid.

[0069] In some embodiments, the method includes the step of condensing at least a portion of the exhaust fluid flow from a gas turbine engine to separate water from at least a portion of the exhaust fluid flow.

[0070] In some embodiments, the water stream is water produced by a condensation process.

[0071] A fourth aspect of the present invention provides a gas turbine engine fluid system comprising a combustion chamber and optionally a cracker optionally located within the combustion chamber, wherein the cracker is optionally configured to provide thermal contact between a combustion fluid in the combustion chamber and a first cracker fluid which optionally passes through a first channel in the cracker and thereby optionally undergoes a first process which optionally chemically decomposes the first cracker fluid into two or more chemical species. By placing the cracker in the combustion chamber, the heat necessary for decomposition can be generated within the cracker. The decomposition products may be useful, in particular, for producing one or more types of fuel or other reactants used in a combustor. For example, the first cracker fluid may be ammonia, which can be decomposed into nitrogen and hydrogen within the cracker. The hydrogen can be used as fuel in the combustor, and / or the nitrogen can be delivered to the combustion chamber for use in cooling and / or reducing the reactivity of at least a portion of the combustion chamber. The latter can support the occurrence of certain forms of combustion, such as flameless combustion in at least a portion of the combustor. This can be advantageous in terms of the nature of the chemical reactions that occur, for example, in reducing undesirable emissions.

[0072] In some embodiments, one of the chemical species is a first fuel for use in combustion in the combustion chamber. The first fuel of the first injection fluid may be delivered from a cracker through the outlet of a first channel and may be separated from one or more other chemical species in an intermediate stage (e.g., a molecular sieve). The molecular sieve may be suitable for separating hydrogen and nitrogen gases decomposed from ammonia in the cracker.

[0073] In some embodiments, the other chemical species is nitrogen. This nitrogen may be delivered to a nitrogen inlet within or adjacent to the secondary combustion zone of the combustor, and at least one nitrogen inlet is configured to deliver nitrogen to the combustion chamber. The secondary combustion zone may be, for example, a flameless combustion zone located downstream of the primary combustion zone where rich combustion occurs. Nitrogen can help create the conditions necessary or desirable for flameless combustion, for example, by reducing reactivity and / or temperature.

[0074] In some embodiments, the cracker is further configured to provide thermal contact between the combustion fluid in the combustion chamber and a second cracker fluid that passes through a second channel in the cracker, thereby undergoing a second process that increases the thermal energy of the second cracker fluid without changing its chemical properties. It may be desirable to raise the temperature of the second cracker fluid. The second cracker fluid may be, for example, fuel for use in a combustor, and as its temperature rises, it can burn more easily and / or with greater efficiency. Additionally or alternatively, the second cracker fluid can cool the cracker.

[0075] In some embodiments, the first cracker fluid and the second cracker fluid have the same composition. The fluids may originate from the same reservoir.

[0076] In some embodiments, the second cracker fluid is a second fuel for use in combustion in the combustion chamber. The second fuel of the second injection fluid may exit the cracker through the outlet of the second channel. The second cracker fluid may be, for example, ammonia.

[0077] In some embodiments, the first and second channels are positioned within the cracker such that the first cracker fluid receives more heat from the combustion chamber fluid than the second cracker fluid. This can be achieved, for example, by positioning the first channel near the high-temperature side of the cracker (e.g., the side facing the primary combustion zone where rich combustion may occur) and the second channel near the low-temperature side of the cracker (e.g., the side facing the secondary combustion zone), or by using materials with different thermal conductivity properties for the different passages. The resulting difference can facilitate different desired heating levels (e.g., heating levels that result in chemical decomposition of the first cracker fluid and simple heating of the second cracker fluid).

[0078] In some embodiments, the system includes a fuel heat exchanger configured to bring into thermal contact at least a portion of the airflow moving into the compressor of a gas turbine engine with a flow of a second fuel moving for injection into the combustion chamber. In this way, the second fuel may be heated before combustion, thereby improving efficiency and / or causing a change of state from a desired storage state (e.g., liquid) to a desired combustion state (e.g., gas) of the second fuel. This can be completed before further heating and / or decomposition of the second fuel in the cracker. Furthermore, the mass of air entering the compressor is increased by its cooling, and therefore the efficiency is potentially increased.

[0079] In some embodiments, the system includes a fuel injector for delivering one or more types of fuel to the combustion chamber. The fuels delivered may be a first fuel and a second fuel.

[0080] In some embodiments, the system includes an exhaust fluid heat exchanger configured to bring into thermal contact at least a portion of the exhaust fluid flow from a gas turbine engine with a flow of water moving for delivery to the system's apparatus and / or combustion chamber. The water may, for example, be converted to steam as a result of passing through the exhaust fluid heat exchanger, and / or delivered as part of a second injection fluid to increase its mass in the combustor, and / or introduced into the combustion chamber via one or more alternative means, for example, one or more alternative ports (dedicated or non-dedicated) in the primary and / or secondary combustion zones. Additionally or alternatively, at least a portion of the steam may be used to preheat the second injection fluid via heat exchange (e.g., via heat exchange in the apparatus) before delivery of the second injection fluid by the apparatus. Additionally or alternatively, particularly if there is an excess of water / steam, the excess water / steam may be used for district heating and / or agriculture.

[0081] In some embodiments, the system includes a condenser configured to cool at least a portion of the exhaust fluid flow from a gas turbine engine and separate water from at least a portion of the exhaust fluid flow. The water may be converted from vapor to liquid water by the condenser, for example, and the condenser can separate water from one or more remaining exhaust fluid components that remain in gaseous form. The exhaust fluid may also contain nitrogen gas, which can be discharged into the atmosphere once separated from water by the condensation process.

[0082] In some embodiments, the water flow that moves for delivery to the fuel injector and / or combustion chamber is water produced by a condenser. Additionally or alternatively, at least a portion of the water produced by the condenser may be used to cool the device.

[0083] In some embodiments, the combustion chamber comprises a primary combustion zone located downstream of the apparatus where rich combustion occurs, and a secondary combustion zone located downstream of the primary combustion zone where flameless combustion occurs. The secondary combustion zone may be located immediately downstream of the primary combustion zone. Compared to the primary combustion zone, the secondary combustion zone may have higher humidity levels in combustion products and / or other reaction products and / or further fluid components and / or higher fuel dilution. In the secondary combustion zone, combustion may occur at temperatures substantially below 1300K. Due to the lower temperature, flameless combustion can help reduce the generation of undesirable emission products, especially when burning fast-reacting fuels such as hydrogen, which may be the first fuel.

[0084] In some embodiments, the combustor can of the combustor may have at least one air inlet in or adjacent to the secondary combustion zone, the at least one air inlet configured to deliver additional air to the combustion chamber. The at least one air inlet may be located close to the beginning of the secondary combustion zone. The at least one air inlet may be configured to generate an axial-tangential swirl, which can promote mixing and residence time for more complete combustion and enhance stability. This air delivery can facilitate the dilution of the first and second fuels present in the secondary combustion zone, enabling combustion in a less noticeable mode and potentially facilitating flameless combustion.

[0085] In some embodiments, the combustor can may have at least one nitrogen inlet in or adjacent to the secondary combustion zone, the at least one nitrogen inlet configured to deliver nitrogen to the combustion chamber. The at least one nitrogen inlet may be located close to the beginning of the secondary combustion zone. The at least one nitrogen inlet may be configured to generate an angular swirl that can promote mixing and residence time for more complete combustion and increase stability. Such nitrogen injection can reduce reactivity and temperature in the secondary combustion zone, further promoting the correct conditions for flameless combustion and / or causing more stable expansion in the turbine downstream of the combustor. The delivered nitrogen may be supplied from a cracker.

[0086] As can be understood, at least one air inlet and at least one nitrogen inlet may be a combined air and nitrogen inlet.

[0087] In some embodiments, the combustion chamber includes a baffle between the primary and secondary combustion zones, which reduces the cross-sectional area of ​​the combustion chamber and thereby creates a flow constriction for the fluid passing from the primary to the secondary combustion zone. The baffle may be substantially centrally located radially within the combustion chamber and define a passage between the primary and secondary combustion zones around the baffle. The passage may be, for example, annular. The baffle may have an upstream-facing projection that may have a central apex. The baffle may be, for example, dome-shaped, conical, truncated cone-shaped, oval-shaped, or spherical. The baffle may help to form recirculation within the primary combustion zone. Specifically, the baffle may help to swirl a flow moving downstream toward the radial end of the combustion chamber so that it moves upstream closer to the center of the combustion chamber.

[0088] According to a fifth aspect of the present invention, a gas turbine engine comprising the system of the fourth aspect is provided.

[0089] A sixth aspect of the present invention provides a method for performing a first process on a first cracker fluid to optionally chemically decompose the first cracker fluid into two or more chemical species, the method optionally comprising passing the first cracker fluid through the combustion chamber of a gas turbine engine, and optionally providing thermal contact between the combustion fluid in the combustion chamber and the first cracker fluid.

[0090] Within the scope of this application, the various aspects, embodiments, examples, and alternative forms, and in particular their individual features, described in the paragraphs, claims, and / or the following description and drawings are expressly intended to be understood individually or in any combination. That is, all embodiments and / or features of any embodiment may be combined in any way and / or in any combination, provided that such features do not conflict. The applicant reserves the right to amend any first filed claim to be dependent on and / or to incorporate any feature of any other claim, even if not initially claimed so, to modify any first filed claim, or to file any new claim accordingly.

[0091] Herein, with reference to the attached drawings, one or more embodiments of the present invention will be described as mere examples. [Brief explanation of the drawing]

[0092] [Figure 1] This is a perspective view of a system according to one embodiment of the present invention. [Figure 2] This is a partial cutaway view of a system according to one embodiment of the present invention. [Figure 3] This is a partial cross-sectional view of a system equipped with a fuel injection device according to one embodiment of the present invention. [Figure 4] This is a partial cutaway view of a system equipped with a cracker according to one embodiment of the present invention. [Figure 5] This is a cross-sectional view showing the fluid flow of a system according to one embodiment of the present invention. [Figure 6] This is a cross-sectional view showing the temperature profile of a system according to one embodiment of the present invention. [Figure 7] This is a schematic diagram of a system according to one embodiment of the present invention. [Figure 8a] This is a perspective view of a part of a system according to one embodiment of the present invention. [Figure 8b] This is a perspective view of a part of a system according to one embodiment of the present invention. [Modes for carrying out the invention]

[0093] First, referring to Figures 1, 2, and 7, the system is shown as 1 overall. System 1 comprises a gas turbine engine shown as 3 overall and a support fluid processing assembly shown as 5 overall. The fluid processing assembly supplies fuel to the gas turbine engine 3 and manages the exhaust products from the gas turbine engine 3.

[0094] The gas turbine engine 3 comprises a compressor 7, a combustor 9, and a turbine 10. As can be understood, depending on the particular embodiment, each of the compressor 7 and the turbine 10 may include multiple stages.

[0095] Figures 1 and 2 show the combustor 9. The combustor 9 has a gas turbine engine fuel injector 11 and a combustion chamber 13.

[0096] The apparatus 11 is shown in detail in Figure 3. The apparatus is configured to deliver a first and a second injection fluid to the combustion chamber 13, in which case the first injection fluid is a first fuel (hydrogen gas), and the second injection fluid is composed of a mixture of a second fuel (ammonia gas), an auxiliary fuel (hydrogen gas), air, and vapor. As a result, the first injection fluid contains the first fuel, which is a fast-reacting fuel, and the second injection fluid contains the second fuel, which is a slow-reacting fuel, and the auxiliary fuel, which is a fast-reacting fuel.

[0097] The first and second injection fluids are delivered to the combustion chamber 13 by corresponding separate first and second outlets 15 and 17. The first outlet 15 for delivering the first injection fluid has an annular cross-section and comprises a ring composed of individual orifices. The second outlet 17 for delivering the second injection fluid also has an annular cross-section, surrounds the first outlet 15, and forms a complete ring around it. The two outlets 15 and 17 are adjacent in the sense that they are close to each other and not separated by any other outlets or structures other than the walls necessary to define them as separate outlets. The first and second outlets 15 and 17 are concentric. In addition, an air outlet 19 configured to deliver air to the combustion chamber 13 is provided so as to be surrounded by the first outlet 15, and the first injection outlet 15 forms a complete ring around it. The air outlet has a circular cross-section and is concentric with the first and second outlets 15 and 17. The air outlet 19 and the first outlet 15 are combined in the burner head 21.

[0098] The first outlet 15, the second outlet 17, and the air outlet 19 are all directed to deliver their corresponding fluids substantially axially, except that the first outlet 15 is angled with respect to the radiating plane to direct the flow direction of the first jet fluid so that it has a radially outward component.

[0099] The first injection fluid is delivered to the first outlet 15 through the first passage 23 of the device 11. The second injection fluid is delivered to the second outlet 17 through the second passage 25, which has an annular cross-section and surrounds the first passage 23. Within the second passage 25 is an angular swirl 27, which gives the second injection fluid an angular swirl as it is delivered through the second outlet 17. Downstream of the angular swirl 27 and upstream of the second outlet 17, the second passage 25 has an auxiliary fuel outlet 29. The auxiliary fuel (in this case, hydrogen) is added through the auxiliary fuel outlet 29 to the remaining component of the second injection fluid that is already flowing toward the second outlet 17 of the second passage 25. The auxiliary fuel is delivered to the auxiliary fuel outlet 29 of the auxiliary fuel passage 31. The auxiliary fuel passage 31 has an annular cross-section and is located between the first passage 23 and the second passage 25, surrounding the first passage 23 and being surrounded by the second passage 25. Air is delivered to the air outlet 19 by an air passage 33, which has a circular cross-section and is surrounded by the first passage 23. In addition, the air passage is equipped with an axial swirl 35.

[0100] A heating fluid chamber 37 surrounds the second passage 25, and the heating fluid chamber 37 has an annular cross-section and is configured such that the heating fluid passing through the heating fluid chamber 37 comes into thermal contact with the second injection fluid in the second passage 25. This allows the second injection fluid to be heated. In this case, the heating fluid is water and / or steam.

[0101] According to the above, the air outlet 19, the first outlet 15, and the second outlet 17 are arranged radially from the inside to the outside with respect to the main outlet. Furthermore, the air passage 33, the first passage 23, the auxiliary fuel passage 31, the second passage 25, and the heated fluid chamber 37 are arranged radially from the inside to the outside with respect to the passages and chambers.

[0102] In this embodiment, the combustion chamber 13 is defined by a substantially cylindrical combustor can 39 having an upstream wall 41, a side wall 43, and a downstream wall 45. Part of the device 11 protrudes through the upstream wall 41 such that a first outlet 15, a second outlet 17, and an air outlet 19 are located axially downstream of the upstream wall 41 of the combustion chamber 13. The first outlet 15, the second outlet 17, and the air outlet 19 share a common central axis with the combustor can 39. Furthermore, the first outlet 15, the second outlet 17, and the air outlet 19 are all substantially axially aligned (although this is not required in other embodiments). The area of ​​the combustion chamber 13 immediately downstream of the first outlet 15, the second outlet 17, and the air outlet 19 (i.e., the first downstream position from which all three fluids are delivered from the corresponding outlets 15, 17, and 19) is the delivery zone 47 of the combustion chamber 13. The delivery zone 47 is surrounded radially outward by the Coanda generator 49. The Coanda generator 49 also extends axially upstream of outlets 15, 17, and 19 to the upstream wall 41, and extends downstream of outlets 15, 17, and 19.

[0103] The Coanda generator 49 has a cylindrical tubular portion 51 extending axially from the upstream wall 41. The tubular portion 51 extends axially beyond the outlets 15, 17, and 19. Downstream of the tubular portion 51, the Coanda generator 49 has a flared portion 53. The flared portion 53 has a continuous tapered portion 55 and a rim portion 57. The continuous tapered portion 55 extends from the tubular portion 51 and has a frustoconical shape. The continuous tapered portion 55 has a radial inner surface with a cross-section that gradually expands downstream, and the radial inner surface of the continuous tapered portion 55 intersects with the radial inner surface of the tubular portion 51 at its edge. In this embodiment, the gradually expanding cross-section forms a slope with a constant gradient. The rim portion 57 extends from the continuous tapered portion 55 and has a downstream surface that extends generally radially. The downstream surface of the rim portion 57 and the radial inner surface of the continuous tapered portion 55 intersect at the edge. When combined, the continuous tapered portion 55 and the rim portion 57 form a bell shape, and the radial inner surface of the tubular portion 51, as well as the downstream surfaces of the continuous tapered portion 55 and the rim portion 51, together have a substantially convex contour.

[0104] The axial range of the Coanda generator downstream of outlets 15, 17, and 19 is smaller than the diameter of the cylindrical tubular portion 51.

[0105] In the combustion chamber 13, a vortex region 59 is formed radially outward from the Coanda generator 49. The vortex region 59 is radially bounded by the radial outer surface 61 of the Coanda generator 49, which has a substantially concave contour, and the side wall 43 of the combustor can 39. The vortex region 59 is axially bounded by the upstream wall 41 of the combustor can 39. The remaining downstream side of the vortex region 59 opens to the rest of the combustion chamber 13.

[0106] At least a portion of the upstream wall 41 of the combustor can 39 is in thermal contact with the heated fluid chamber 37, and the heated fluid chamber 37 also surrounds the second passage 25 and is in thermal contact with the second passage 25. In this way, the heated fluid (e.g., water and / or steam) can also serve to cool the fluid in the vortex region 59 via the heated fluid chamber 37 and the upstream wall 41. In certain embodiments, the heated fluid can be recirculated, discharged, or injected into the combustion chamber 13 to enhance the humidification of the vortex region 59 and / or to further lower the temperature of the fluid in the combustion chamber 13.

[0107] Next, referring to Figures 8a and 8b, in this embodiment, a portion of the heated fluid is injected from the heated fluid chamber 37 through the upstream wall 41 into the combustion chamber 13 via a series of ports 42a. The ports 42a are configured to inject the heated fluid in a direction substantially perpendicular to the upstream surface 42b of the combustor can 39. The upstream surface 42b is sloped radially such that the upstream surface 42b moves further downstream from the radially outward to the radially inward direction. This injection of heated fluid perpendicular to the inclined upstream surface 42b can help form a vortex in the fluid within the vortex region 59.

[0108] The upstream wall 41 of the combustor can 39 has a configuration that increases the surface area of ​​the upstream wall 41 compared to a flat plate configuration. In particular, the upstream wall 41 includes a corrugated structure 42c in its structure, resulting in a pattern of alternating peaks 42d and troughs 42e in the circumferential direction, with each peak 42d and trough 42e extending radially. This pattern is present on both the upstream surface 42b of the combustor can 39 and the opposite surface 42f facing the heated fluid chamber 37.

[0109] The combustor canister 39 has a waist portion 63 that is tapered so that its radial inner surface diameter decreases. The waist portion 63 is positioned to substantially align with a ring that indicates the intersection point between the projection on the radial inner surface of the continuous tapered portion 55 and the side wall 43 of the combustor canister 39, with respect to its axial position.

[0110] The combustion chamber 13 is broadly divided into a primary combustion zone 65, which substantially corresponds to its upstream half, and a secondary combustion zone 67, which substantially corresponds to its downstream half. The primary combustion zone 65 and the secondary combustion zone 67 are distinguished from each other by two features (in this embodiment). Aligned substantially axially with the transition from the primary combustion zone 65 to the secondary combustion zone 67 is an air and nitrogen inlet 69 passing through the side wall 43 of the combustor can 39. The air and nitrogen inlet 69 comprises a plurality of ports 71 arranged at regular intervals in the angular direction. Each port 71 is angled to generate an angular swirl of the injected mixture of air and nitrogen. The air and nitrogen inlet 69 is supplied with air from the compressor 7 via an annular duct (not shown) that is radially outside the primary combustion zone portion of the combustion can 39 and surrounding it.

[0111] In addition, a baffle 73 is substantially axially aligned with the transition from the primary combustion zone 65 to the secondary combustion zone 67. This is best seen in Figures 2 and 4. The baffle 73 is supported at the center of the combustion chamber 13, thereby locally reducing the cross-sectional area of ​​the combustion chamber 13 to an annular portion between the outer circumference of the baffle and the side wall 43 of the combustor can 39. In this embodiment, the baffle 73 is substantially elliptical in shape and has a projection facing upstream with a central vertex 75. In this embodiment, the baffle 73 is also a cracker. The cracker 73 has internally a first channel and a second channel (not shown) connected to corresponding inlets and outlets that pass through a structure supporting the cracker 73 within the combustion chamber 13. The first and second channels are positioned within the cracker 73 such that the first channel is closer to the upstream end of the cracker 73 than the second channel. Since combustion is hotter in the primary combustion zone 65 than in the secondary combustion zone 67, the first cracker fluid passing through the first channel is heated more (e.g., up to about 700°C) than the second cracker fluid passing through the second channel (e.g., about 400°C). In this embodiment, the first and second cracker fluids have the same composition and are ammonia. In the first channel, ammonia is chemically decomposed into hydrogen gas (first fuel) and nitrogen gas. In the second channel, ammonia is not chemically decomposed but is instead heated.

[0112] The outlet of the first channel leads to a molecular sieve (not shown) for separating chemical species (in this case, separating hydrogen gas from nitrogen gas). From the molecular sieve, the separated hydrogen is led to the first passage 23 and the auxiliary fuel passage 31. The nitrogen gas separated by the molecular sieve is led to the air and nitrogen inlet 69 for mixing with air and being injected into the secondary combustion zone 67.

[0113] The outlet of the second channel leads to a second passage 25 for delivering heated ammonia for use as a second fuel for the second injection fluid. The inlet to the second channel receives the ammonia from a fuel heat exchanger 77 (see Figure 7). The fuel heat exchanger 77 receives a supply of ammonia from a fuel tank (not shown) and brings the ammonia into thermal contact with at least a portion of the airflow moving to the compressor 7 of the gas turbine engine 3. The ammonia delivered to the inlet to the second channel of the cracker 73 is heated by passing through the fuel heat exchanger 77. Furthermore, the expansion of liquid ammonia into gaseous ammonia cools the airflow moving to the compressor 7.

[0114] Further fluid processing is performed by the exhaust fluid heat exchanger 79 (see Figure 7). Steam and nitrogen are generated in the combustion process and recovered from the exhaust of the gas turbine engine 3. At least a portion of this exhaust fluid flow comes into thermal contact with a water flow. The water flow is delivered to the second passage 25 for use as a component of the second injection fluid, and then delivered to the heated fluid chamber 37 to heat the second injection fluid in the second passage 25, cool the fluid in the combustion chamber 13, and deliver it to the vortex region 59 for cooling and dilution purposes. The water flow itself originates from the exhaust fluid flow. After the exhaust fluid flow passes through the exhaust fluid heat exchanger 79, it passes through the condenser 81. In the condenser 81, water in the exhaust fluid is also separated from nitrogen. While the water is delivered to the exhaust fluid heat exchanger 79, the nitrogen is discharged into the atmosphere. The water also dilutes residual NOx and unburned ammonia emission products from the combustion process.

[0115] When System 1 is in use, the second fuel, liquid ammonia fuel, is pumped from the fuel tank to the fuel heat exchanger 77, where it undergoes heat exchange with at least a portion of the airflow flowing into the compressor 7. This heat exchange increases the thermal energy of the ammonia, improving combustion efficiency. This heat exchange also changes the state of the ammonia from liquid to gaseous as it was in storage, cooling the airflow moving to the compressor and increasing the mass of air passing through the gas turbine engine 3. Subsequently, a portion of the ammonia is pumped through a second channel in the cracker 73. In the second channel, as the second cracker fluid, the ammonia undergoes a second process in which its thermal energy is further increased through heat exchange with the combustion fluid in the combustion chamber 13. The ammonia is then pumped into the second passage 25 for final delivery as the second fuel and as a component of the second injection fluid.

[0116] Meanwhile, another portion of the ammonia fuel from the fuel heat exchanger 77 passes through the first channel of the cracker 73. There, as the first cracker fluid, the ammonia undergoes a first chemical decomposition process resulting from heat exchange with the combustion fluid of the combustion chamber 13, becoming two chemical species: hydrogen and nitrogen. The hydrogen and nitrogen are then pumped through a molecular sieve to separate them. The hydrogen, which is the first fuel, is pumped into the first passage 23 for use as the first injection fluid and into the auxiliary fuel passage 31 for use as an auxiliary fuel. In this way, the first fuel is produced from the second fuel by system 1. The nitrogen is pumped into the air and nitrogen inlet 69.

[0117] Within the apparatus 11, the first fuel, i.e., hydrogen gas, which constitutes the first injection fluid in this embodiment, is pressurized through the first passage 23 to exit through the first outlet 15 at the burner head 21. At the time of delivery, the hydrogen injected by the first outlet 15 is delivered in a first flow with an annular cross-section that moves substantially axially downstream, but is given some radially outward component by the angle of the first outlet 15 with respect to the radiating plane. Once the first flow is delivered, it is partially combined with swirl air, which is also delivered simultaneously from the air outlet 19 at the burner head 21. The air delivered from the air outlet 21 is delivered to the air outlet by the compressor 7 and passes through the air passage 33 and its axial swirl 35.

[0118] Within the apparatus 11, the second fuel in the second passage 25, i.e., ammonia gas, is mixed with air delivered to the second passage 25 by the compressor 7 and water and / or vapor injected into the second passage 25 from heated water arriving from the exhaust fluid heat exchanger 79 via the heated fluid chamber 37. This mixture passes through a portion of the second passage 25 having an angled swirler 27. Subsequently, hydrogen gas is introduced into the second passage 25 by the auxiliary fuel passage 31 and auxiliary fuel outlet 29, thereby mixing with the ammonia, air, and vapor already present in the second passage. The resulting mixture constitutes the second injection fluid, which is pressurized through the second outlet 17. At the time of delivery, the second injection fluid injected by the second outlet 17 is delivered in a second flow with an annular cross-section and moves substantially axially downstream. The second flow substantially surrounds the first flow as the two flows are delivered to the delivery zone 47. Therefore, any movement in a radially outward direction from substantially any portion of the first flow will encounter the second flow. In this embodiment, in addition to water and / or steam from the exhaust fluid heat exchanger 79 being injected into the second passage 25, they are also separately injected directly into the vortex region 59 via port 42a, but it should be noted that in other embodiments, only one or the other of these may occur, or neither may occur.

[0119] The amounts of the components of the first and second injection fluids, and the amount of water and / or steam injected directly into the vortex region 59, can be selected such that the total amount of steam injected is 0% to 40% of the total amount of fuel injected (i.e., the fuel and steam are injected in a fuel-to-steam ratio of 5:2, or some higher fuel-to-steam ratio).

[0120] Upon delivery to the delivery zone 47, the first flow is ignited by an igniter (not shown). The effect of the axial swirl 35 on the air delivered from the air outlet 21 can cause a swirl flame in the ignited hydrogen, which can then recirculate near the delivery zone 47 via vortex breaking. The hydrogen in the first flow is easily ignited, but the ammonia in the second flow is not so easily ignited. The ignited hydrogen in the first flow acts as a pilot for igniting the ammonia in the second flow. Therefore, the hydrogen in the first flow serves a useful purpose in igniting the ammonia in the second flow, but its combustion mechanism in this high-temperature initial stage of the combustion process produces nitrogen oxides, which are undesirable from the viewpoint of emissions (i.e., (H2 + (O2 + N2 (air)) => NOx + H2O). However, the unburned ammonia and ammonia radicals (e.g., NH2) in the second flow can reduce the nitrogen oxides back to nitrogen (i.e., NH3 + NOx => N2 + H2O), and the combustion temperature conditions are approximately 1200-1600K, with an ammonia concentration of approximately 30-40%. The first flow is surrounded by the second flow as the flow enters the delivery zone 47 and the primary combustion zone 65, so the hydrogen produced by the combustion of the hydrogen of the first fuel and the ammonia of the second fuel is produced. The nitrogen oxides produced are more likely to encounter unburned ammonia and ammonia radicals from the second fuel and thus be reduced. The first flow, which has a component in the direction of travel toward the second flow (as a result of the angle of the first outlet 15), can also increase this possibility. Recirculation occurring near the delivery zone 47 as a result of the axial swirl 35 increases the residence time and therefore can increase the proportion of delivered hydrogen that burns at this stage to produce nitrogen oxides. Burning a larger proportion of hydrogen at this stage may be advantageous considering the nitrogen oxides produced are more likely to encounter unburned ammonia and ammonia radicals from the second fuel in the surrounding second flow (i.e., due to the direction of travel of the surrounding second flow and the first flow).Furthermore, because the second injecting fluid (and thus the ammonia of the second fuel) is delivered radially outward from the first injecting fluid, it is somewhat shielded / removed from the burning, and therefore hottest, flame core, allowing the additional ammonia to be stored unburned. This, in turn, may be available for the reduction of nitrogen oxides.

[0121] As the first and second flows move downstream, they successively encounter two distinct low-pressure zones in the radially outward direction, formed by the continuous tapered portion 55 and rim portion 57 of the Coanda generator, respectively. These tend to increase the component of the fluid in the direction of movement in the radially outward direction, bending and flattening the flame to some extent. This tends to lower the temperature of the burner head 21 to some extent, reducing its stress and potentially reducing the need for its maintenance / replacement. As understood, the distinct first and second flows gradually lose their identity and mix, at least to some extent, resulting in a more general mixture of the combustion fluid as well as other reactants and components. The combustion fluid continues to move downstream and radially outward. The initial effect of the Coanda generator 49 in bending the flame, the combination of the waist 63, side walls 43, and upstream wall 41 of the combustor can 39, and the radially outward surface 61 of the Coanda generator 49 tends to form vortex stagnation of the fluid mixture within the vortex region 59. In addition, the combination of the initial effect of the Coanda generator 49 when bending the flame, the waist 63 and side walls 43 of the combustor can 39, and the partial blockage of the outlet from the primary combustion zone 65 by the cracker 73 tends to cause the formation of a larger central recirculation. This allows the rest of the primary combustion zone 65 to be substantially filled with post-combustion high-temperature radicals in the oxygen-depleted region, and thus further promotes the reduction of nitrogen oxides.

[0122] The formation of vortex stagnation in the vortex region 59 can be further facilitated by both the corrugated structure 42c (which may have a tendency to guide the fluid substantially radially) and the water and / or vapor injected through the port 42a (injection direction having radially inward and downstream components).

[0123] Figure 5 shows the bending effect of the Coanda generator 49, and Figure 6 shows the initial stages of vortex stagnation and larger central recirculation formation. Both vortex stagnation and larger central recirculation increase the residence time of the fluid in the combustion chamber 13, particularly in the primary combustion zone 65. This allows for more time, resulting in further mixing to promote the reduction of nitrogen oxides by trace amounts of unburned ammonia and unreacted ammonia radicals. In addition, vortex stagnation, water temperature control, and central recirculation somewhat lower the temperature of the primary combustion zone 65, and this lowering can lead to a more suitable temperature (i.e., within the range of 1200-1500K). The vapor component of the second injection fluid can also help lower the temperature, as well as increase the mass of the fluid and thus the power generated. When recirculation occurs, the presence of hydrogen in the second injection fluid can help the continuous ignition of unburned ammonia.

[0124] Furthermore, the water and / or steam injected from the heated fluid chamber 37 through port 42a, as well as the corrugated structure 42c which increases heat exchange with the water and / or steam in the heated fluid chamber 37, help to lower the temperature of the fluid in the combustion chamber 13.

[0125] Finally, a considerable proportion of hydrogen and ammonia are burned here, and the mixture of fluids, diluted with a considerable amount of water and nitrogen components, passes through the annular section between the periphery of the cracker 73 and the side wall 43 of the combustor can 39. Thus, the mixture enters the secondary combustion zone 67. As the mixture of fluids passes through the cracker 73, it heats the cracker 73, thereby enabling the cracker to function as described above and facilitating heat exchange with the fluids in its first and second channels.

[0126] To provide additional air for combustion and further dilute the fluid mixture, air and nitrogen are injected through multiple ports 71 at the upstream end of the secondary combustion zone to form the desired combustion conditions (described further below). In addition, the swirl provided by the properties of the multiple ports 71 helps to increase mixing and retention within the secondary combustion zone 67.

[0127] As mentioned above, combustion of hydrogen at relatively high temperatures produces undesirable nitrogen oxides. Therefore, if sufficient hydrogen is burned in the higher-temperature primary combustion zone 65 and the ammonia of the second injection fluid is properly ignited, it is preferable that the remaining hydrogen be burned mainly in another way. Furthermore, ammonia combustion under rich conditions also leads to hydrogen production, and this hydrogen is generally known not to burn in the primary zone due to oxygen deficiency. In the case of pure hydrogen, it is desirable that combustion occur at approximately 1200% to below 1300K to reduce nitrogen oxide formation. This can be achieved in the secondary combustion zone 67 where flameless combustion occurs. In flameless combustion, there is no flame, and the combustion of hydrogen occurs in discrete mode. This can occur with sufficiently diluted reactants (e.g., hydrogen and oxygen diluted with water and nitrogen) and a sufficiently low temperature. That is, hydrogen and oxygen molecules are present to react, but they are sufficiently diluted so that the reaction per unit volume is insufficient to produce a visible flame. Such conditions may prevail in the secondary combustion zone 67 due to several factors. Firstly, most of the hydrogen is already burned in the primary combustion zone 65. Secondly, combustion in the primary combustion zone 65 produces diluents (mainly water and nitrogen), and increasing the residence time in the primary combustion zone 65 increases the production of these diluents, increasing mixing and allowing for a decrease in temperature. Water and nitrogen can constitute more than 90% and possibly more than 95% of the material that reaches the secondary combustion zone 65. Thirdly, the injection of nitrogen through multiple ports 71 further dilutes the reactants for delivery to the secondary combustion zone 67. It should be further noted that the position of the first outlet 15 (i.e., more radially inward / central) means that the hydrogen of the first injection fluid tends to be less likely to be recirculated in the primary combustion zone 65 than the components of the second injection fluid, and instead tends to follow a more direct path to the secondary combustion zone 67. This can be beneficial in that less hydrogen can be burned in the primary combustion zone 65 and more hydrogen can be burned in the secondary combustion zone 67.

[0128] Combustion products are emitted from the secondary combustion zone 67. The exhaust fluid flow is mainly water and nitrogen. The water component may be about 30% to 40%. This may be in contrast to conventional gas turbine engines that operate on conventional fossil fuels, where the water concentration may be less than about 10%. After passing through the turbine 10, the exhaust products are led to the exhaust fluid heat exchanger 79. In the exhaust fluid heat exchanger 79, thermal energy from the exhaust fluid flow is transferred to the water flow (raising the temperature of the water). The water flow is pressurized into the heating fluid chamber 37 to heat the second injection fluid in the second passage 25 and control the temperature of the vortex region 59. A portion of it is then injected into the vortex region 59 through port 42a, and the remainder is pressurized into the second passage 25 to be used as a component of the second injection fluid. The water in the water flow originates from the exhaust fluid flow. After the exhaust fluid flow passes through the exhaust fluid heat exchanger 79, the fluid passes through the condenser 81. In the condenser 81, the water in the exhaust fluid is also separated from the nitrogen. While water is being pumped into the exhaust fluid heat exchanger 79, nitrogen is discharged into the atmosphere.

[0129] In this way, System 1 generates its own fuel and reactants from a single type of fuel that is introduced, and utilizes a portion of the thermal energy and exhaust products it generates.

[0130] All of the features disclosed herein (including the attached claims, abstract, and drawings) and / or all of the steps of any method or process disclosed herein may be combined in any combination, except for any combination in which at least some of such features and / or steps are mutually exclusive.

[0131] Each feature disclosed herein (including the attached claims, abstract, and drawings) may be replaced by an alternative feature serving the same, equivalent, or similar purpose unless otherwise specified. Therefore, unless otherwise specified, each disclosed feature is merely an example of a general set of equivalent or similar features.

[0132] The present invention is not limited to any details of any of the embodiments described above. The present invention extends to any novel features or any novel combination of features disclosed herein (including the appended claims, abstract, and drawings), or any novel step or any novel combination of any step of any method or process so so disclosed. The claims should be construed to encompass not only the embodiments described above, but also any embodiments included within the claims. As an example, one embodiment of a system comprising a cracker and associated combustion chamber can be used independently of and / or in conjunction with other system features of the rest of the system described in the embodiments described above. For example, one embodiment of a system comprising a cracker and associated combustion chamber can be used in conjunction with different gas turbine engines, for example, in which the fuel used and / or the way they are delivered may differ. As a further example, in the embodiments described above, steam is injected through the upstream wall 41 of the combustor can 39 as part of a second injection fluid, but in other embodiments, only one or only one of these may occur, or neither may occur. [Explanation of Symbols]

[0133] 1 System, 3 Gas turbine engine, 5 Support fluid handling assembly, 7 Compressor, 9 Combustor, 10 Turbine, 11 Gas turbine engine fuel injector, 13 Combustion chamber, 15 First outlet, 17 Second outlet, 19 Air outlet, 21 Burner head, 23 First passage, 25 Second passage, 27 Angular swirl, 29 Auxiliary fuel outlet, 31 Auxiliary fuel passage, 33 Air passage, 35 Axial swirl, 37 Heating fluid chamber, 39 Combustor can, 41 Upstream wall, 42a Port, 42b Upstream surface, 42c Corrugation structure, 42d Peak, 42e Trough, 42f Opposite surface, 43 Side wall, 45 Downstream wall, 47 Delivery zone, 49 Coanda generator, 51 Tubular section, 53 Flared section, 55 Continuous tapered section, 57 Rim section, 59 Vortex region, 61 Radial outer surface, 63 Waist, 65 Primary combustion zone, 67 Secondary combustion zone, 69 Air and nitrogen inlet, 71 Port, 73 Cracker / baffle, 75 Central apex, 77 Fuel heat exchanger, 79 Exhaust fluid heat exchanger, 81 Condenser

Claims

1. A system comprising a fuel injection device configured to deliver a first injection fluid containing a first fuel and a second injection fluid containing a second fuel to a combustion chamber, The first fuel comprises a fast-reacting fuel, and the second fuel comprises a slow-reacting fuel. A system in which the apparatus is configured to deliver the first and second injection fluids, so that the first injection fluid is delivered in a first flow and the second injection fluid is delivered in a second flow, the first and second flows are delivered in substantially the same direction and from separate corresponding first and second outlets, and there exists a delivery zone corresponding to the first location where both the first and second flows are delivered, and the first flow is substantially radially surrounded by the second flow.

2. The system according to claim 1, comprising an air outlet configured to deliver air for combustion with the first fuel and the second fuel after delivery, the air outlet being located radially inward of the first outlet and radially surrounded by the first outlet.

3. The system according to claim 1 or 2, wherein the initial combustion of at least a portion of the first injectable fluid in the first flow acts as a pilot for ignition of at least a portion of the second injectable fluid in the second flow.

4. The system according to any one of claims 1 to 3, wherein the delivery zone is radially surrounded and defined by a Coanda generator to which the first and second injection fluids are delivered by the device.

5. The system according to claim 4, wherein the Coanda generator comprises a tubular portion that radially surrounds the apparatus, the tubular portion has a radial inner surface with a certain cross-section, and a flared portion is connected to the radial inner surface downstream of the tubular portion.

6. The system according to claim 5, wherein the radial inner surface of the tubular portion and the radial inner surface of the continuous tapered portion intersect at a discontinuity in the form of the edge.

7. The system according to claim 6, wherein the flared portion is connected to the continuous tapered portion and comprises a rim portion having a substantially radially extending downstream surface.

8. The system according to claim 7, wherein the radial inner surface of the continuous tapered portion and the downstream surface of the rim portion intersect at a discontinuity in the form of an edge.

9. The system according to any one of claims 4 to 8, wherein the Coanda generator extends into a combustion chamber defined by the combustor can, and forms a vortex region radially bounded by the radial outer surface of the Coanda generator and the radial inner surface of the combustor can, and axially bounded by the upstream surface of the combustor can.

10. The system according to claim 9, further comprising a heating fluid chamber positioned in thermal contact with the upstream wall of the combustor can of the combustion chamber.

11. The system according to any one of claims 1 to 8, further comprising a heating fluid chamber positioned in thermal contact with the upstream wall of the combustor can of the combustion chamber.

12. The system according to any one of claims 1 to 11, wherein the combustion chamber comprises a primary combustion zone located downstream of the apparatus where rich combustion occurs, and a secondary combustion zone located downstream of the primary combustion zone where flameless combustion occurs.

13. The system according to any one of claims 1 to 12, wherein a cracker is placed in the combustion chamber, and the combustion chamber is configured to provide thermal contact between a combustion fluid in the combustion chamber and a first cracker fluid that passes through a first channel in the cracker, thereby undergoing a first process that chemically decomposes the first cracker fluid into two or more chemical species.

14. The system according to claim 13, wherein one of the chemical species is the first fuel.

15. The system according to claim 13 or 14, wherein the cracker is further configured to provide thermal contact between the combustion fluid in the combustion chamber and the second cracker fluid, which passes through a second channel in the cracker and thereby undergoes a second process that increases the thermal energy of the second cracker fluid without changing its chemical properties.

16. The system according to claim 15, wherein the second cracker fluid is the second fuel.

17. The system according to any one of claims 1 to 16, wherein the fuel injection device is a gas turbine engine fuel injection device and the combustion chamber is a combustion chamber of a gas turbine engine.

18. The system according to claim 17, wherein the system comprises a fuel heat exchanger, the fuel heat exchanger is configured to bring into thermal contact at least a portion of the airflow moving into the compressor of the gas turbine engine with the flow of the second fuel moving to be delivered by the device in the second injection fluid.

19. The system according to claim 17 or 18, further comprising an exhaust fluid heat exchanger configured to bring into thermal contact at least a portion of the exhaust fluid flow from the gas turbine engine with a flow of water moving for delivery to the apparatus and / or the combustion chamber.

20. A gas turbine engine comprising the system according to any one of claims 17 to 19.

21. A method for injecting fuel in a gas turbine engine, The process includes the step of delivering a first injection fluid containing a first fuel and a second injection fluid containing a second fuel to a combustion chamber. The first fuel comprises a fast-reacting fuel, and the second fuel comprises a slow-reacting fuel. A method wherein the delivery step is such that the first injection fluid is delivered in a first flow and the second injection fluid is delivered in a second flow, and the first and second flows are delivered in substantially the same direction and from separate corresponding first and second outlets, and there exists a delivery zone corresponding to the first location, at which both the first and second flows are delivered, and the first flow is substantially radially surrounded by the second flow.

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