Combustion for gas turbines

Abstract

A combustor (36) for a gas turbine includes a combustor axis (44) around which a radial swirler (40), a pre-combustion chamber (42), and a combustion chamber (38) are arranged in flow sequence. The radial swirler (40) includes a base plate (45), an annular array of swirler blades (46) defining swirler slots (47) arranged around the base plate (45), main fuel injectors (48A, 48B) for injecting main fuel, and an ignition fuel injector (50) for injecting ignition fuel. The combustor includes a premixer nozzle (70) located on the combustion chamber (38). The premixer nozzle (70) includes a housing (78), an array of tubes (80) located within the housing (78), and a first fuel passage (72) for supplying a first fuel (83). Each tube (80) in the array of tubes (80) includes an inlet (86), an outlet (88), a first orifice (90), and a second orifice (92). A first fuel passage (72) is arranged to supply first fuel (83) to the first orifice (90) and / or the second orifice (92). In use, air (34) is supplied to the burner, and a first portion of air (34A) passes through a radial vortex (40), while a second portion of air (34B) passes from the inlet (86) through the tubes (80) in the array of tubes (80) to the outlet (88) and mixes with the first fuel (83) passing through the first orifice (90) and / or the second orifice (92).

Description

Technical Field

[0001] The present invention relates to burners for gas turbines, and specifically, but not exclusively, to distributed combustion systems suitable for burning fuels with a high hydrogen content or high hydrocarbon content without producing backfire. Background Technology

[0002] Current dry low-emission (DLE) combustion systems include radial cyclones having an annular array of blades with grooves defined therebetween. Compressed air passes through the cyclones in a radially inward and tangential direction to create a vortex-like fuel-air mixture. The fuel-air mixture passes through a pre-combustion chamber and enters the combustion chamber, where it is combusted. The DLE combustion system includes a main fuel supply and a pilot fuel supply. Typically, the main fuel supply, consisting of gaseous fuel, is injected from two locations in each groove of the radial cyclone. In one location, a fuel injection orifice is located at the base of each groove near the groove's inlet, i.e., in the radially outer portion of the groove. In another location, two side injection orifices are located on the blades in each groove. Mixing of the main fuel can be aided by positioning the injector nozzles in countersunk orifices. The pilot fuel injector is located on a base plate that defines the axial extent of the pre-combustion chamber and is typically located radially inward of the cyclone blades.

[0003] In a DLE combustion system, two distinct flames are formed. The main flame is produced by the injection of premixed main fuel, while the flame injected from the ignition injector is a diffusion flame. A known burner has an additional fuel injection location compared to the main and ignition injectors, and is located axially downstream. This is called a distributed combustion system (DCS) or axial fuel staged combustion chamber. The primary purpose of using axial fuel staged combustion is to reduce CO at low loads or to maintain efficiency and reduce NOx emissions by distributing the flame to lower the overall peak temperature within the combustion chamber.

[0004] However, in known DCS systems, fuel injected via another fuel injection device can only be premixed to achieve the aforementioned purpose. Therefore, diffusion flames are not possible in DCS systems using existing technology. Furthermore, any premixing will also lead to flame backfire or flame persistence if any local stagnation or recirculation zone is created. Therefore, it is impossible to use fuels with high hydrocarbon content and large hydrogen content in conventional distributed combustion systems because backfire will occur. Summary of the Invention

[0005] Therefore, the purpose of the currently disclosed burner is to provide a combustion system that prevents flame backfire and provides efficient combustion with low emissions. Another purpose of the currently disclosed burner is to provide better mixing of fuel and air. Yet another purpose of the currently disclosed burner is to provide a more stable combustion process.

[0006] The aforementioned objective is achieved by a combustor for a gas turbine, the combustor comprising a combustor axis around which a radial swirler, a pre-combustion chamber, and a combustion chamber are arranged in flow sequence. The radial swirler comprises: a base plate; an annular array of swirler blades defining swirler slots arranged around the base plate; a main fuel injector for injecting main fuel; and a pilot fuel injector for injecting pilot fuel. The combustor also includes a premixer nozzle located on the combustion chamber. The premixer nozzle comprises: a housing; an array of tubes within the housing; and a first fuel passage for supplying first fuel. Each tube in the array of tubes includes an inlet, an outlet, a first orifice, and a second orifice. The first fuel passage is arranged to supply first fuel to the first orifice and / or the second orifice. In use, air is supplied to the burner, and a first portion of the air passes through a radial vortex, while a second portion of the air passes from the inlet through an array of tubes to the outlet and mixes with the first fuel passing through the first orifice and / or the second orifice.

[0007] The premixer nozzle may include a second fuel passage for supplying a second fuel to a second orifice. In use, a second portion of air passes from the inlet through an array of tubes to the outlet and mixes with the first fuel from the first fuel passage passing through the first orifice and the second fuel from the second fuel passage passing through the second orifice.

[0008] At least one tube in the array of tubes, preferably all tubes, may include a converging portion that converges toward an outlet, preferably terminating at the outlet.

[0009] The converging portion may have a first cross-sectional area and a second cross-sectional area, the second cross-sectional area being downstream of the first cross-sectional area, and the reduction in cross-sectional area between the first and second cross-sectional areas falling within the range of 10% to 40% of the first cross-sectional area.

[0010] The fuel and air mixture can exit the pipe outlet at speeds between 60 m / s and 100 m / s, including both.

[0011] The first fuel and / or the second fuel can exit at least one of the orifices and enter the pipe at a speed between 50 m / s and 80 m / s, including 50 m / s and 80 m / s.

[0012] The first and second orifices can span across the pipe and face each other, so that the corresponding jets of the first and second fuels collide with each other.

[0013] The first and second orifices can be directly opposite each other across the pipe and aligned with each other.

[0014] The first and second openings can have different areas.

[0015] At least one tube, preferably the central tube (80A), may not have a first or second orifice.

[0016] At least one pipe may have a third fuel supply device for supplying a third fuel, preferably a liquid fuel.

[0017] The first fuel and / or the second fuel can be any one or a combination of natural gas, hydrogen, fuel containing at least 5% hydrogen, and higher hydrocarbon fuels such as liquefied petroleum gas.

[0018] The combustion chamber may include an array of premixer nozzles, which preferably has between four and eight premixer nozzles, and includes both four and eight premixer nozzles.

[0019] The premixer nozzles can be evenly spaced around the circumference of the combustion chamber.

[0020] The premixer nozzles can be arranged such that some of the premixer nozzles are axially offset relative to the other premixer nozzles.

[0021] Any or more of the main fuel, ignition fuel, first fuel, second fuel, and third fuel can be supplied via fuel supply lines and valves, which can be controllable and connected to a controller.

[0022] The controller can be configured to change the amount of any or more of the main fuel, ignition fuel, first fuel, second fuel, and third fuel individually, jointly, or simultaneously.

[0023] In a second aspect of this disclosure, a method for injecting fuel into a burner according to any of the preceding paragraphs is provided, wherein the method includes at least one of the following steps: injecting fuel from at least one orifice in the orifice at a speed between 50 m / s and 80 m / s and including 50 m / s and 80 m / s into at least one tube; and injecting a fuel and air mixture from the outlet of at least one tube at a speed between 60 m / s and 100 m / s and including 60 m / s and 100 m / s. Attached Figure Description

[0024] The above-described properties and other features and advantages of the present technology, as well as the ways of obtaining these properties and other features and advantages, will become more apparent from the following description of embodiments of the present technology taken in conjunction with the accompanying drawings, and the currently disclosed burner and operating method will be better understood.

[0025] Figure 1 A portion of the turbine engine is shown in cross-section, and a combustor according to this disclosure is incorporated into the turbine engine.

[0026] Figure 2 It is a schematic cross-section through the currently disclosed burner, and shows the premixer nozzle.

[0027] Figure 3 This is a schematic cross-section through the first embodiment of the premixer nozzle currently disclosed.

[0028] Figure 4 Is it like this? Figure 3 The cross-sectional view of the premixer nozzle shown is SA-SA.

[0029] Figure 5 This is another cross-sectional view SA-SA of an alternative implementation of the premixer nozzle.

[0030] Figure 6 This is a schematic cross-section through the second embodiment of the premixer nozzle currently disclosed.

[0031] Figure 7 This is an enlarged view of one of the tubes in the array of premixer nozzles.

[0032] Figure 8 This is an enlarged view of an alternative implementation of one tube in an array of tubes for a premixer nozzle. Detailed Implementation

[0033] Figure 1This is a schematic diagram of the overall arrangement of a turbine engine 10, which includes an inlet 12, a compressor 14, a combustor system 16, a turbine system 18, an exhaust duct 20, and twin shaft units 22 and 24. The turbine engine 10 is generally arranged about an axis 26, which is the axis of rotation for rotating components. The shafts of the twin shaft units 22 and 24 may have the same or opposite directions of rotation. The combustor system 16 comprises an annular array of combustors 36, with only one combustor shown. In one example, there are six combustors 36 evenly spaced around the engine 10. The turbine system 18 includes a high-pressure turbine 28 driven to the compressor 14 via a first shaft 22 of the twin shaft unit. The turbine system 18 also includes a low-pressure turbine 30 driven to a load (not shown) via a second shaft 24 of the twin shaft unit.

[0034] The terms "radial," "circumferential," and "axial" are relative to the engine's axis of rotation 26, or as otherwise stated. The terms "upstream" and "downstream" are relative to the general direction of gas flow through the engine, and as... Figure 1 What we see is usually from left to right.

[0035] Compressor 14 includes an axially arranged series of stator blades and rotor blades mounted in a conventional manner. The stator or compressor blades may be fixed or have variable geometry to improve airflow to the downstream rotor or compressor blades. Each turbine 28, 30 includes an axially arranged series of stator blades and rotor blades. The stator blades may be mounted to a radial housing or radial inner cylinder. The rotor blades are mounted via a rotor disk arranged and operated in a conventional manner. The rotor assembly includes rotor blades or an annular array of blades and a rotor disk.

[0036] Each burner 36 consists of two walls—an inner wall 37 and an outer wall 39—defining a generally annular space between the inner wall 37 and the outer wall 39. At the head of the burner 36 is a radial swirler 40, which includes a swirl plate or base plate 45, an annular array of swirler blades 46, and fuel injection points, as described in more detail later. Following the swirler 40 is a pre-combustion chamber 42, and then a main combustion chamber 38. These burner components 36 are generally arranged about a burner axis 44. The annular array of swirler blades 46 defines swirler slots 47 arranged around the base plate 45.

[0037] In operation, air 32 is drawn into the engine 10 through inlet 12 and enters the compressor 14, where the impellers and blades of the continuous stage compress the air 34 before it is delivered to the combustor system 16. The compressed air 34 flows between the inner wall 37 and the outer wall 39 and enters the cyclone separator 40. The cyclone separator 40 generates highly turbulent air into which fuel is injected. The air / fuel mixture is delivered to the pre-combustion chamber 42, where it continues to mix, and then to the main combustion chamber 38. In the combustion chamber 38 of the combustor 36, the compressed air and fuel mixture is ignited and burned. The resulting hot working gas stream is directed to the high-pressure turbine 28, causing the turbine to expand and drive the compressor 14 via the first shaft 22. After passing through the high-pressure turbine 28, the hot working gas flow is directed into the low-pressure turbine 30, which drives the load via the second shaft 24.

[0038] The low-pressure turbine 30 can also be referred to as a power turbine, and the second shaft 24 can also be referred to as a power shaft. The load is typically an electric motor for generating electricity or a mechanical machine such as a pump or process compressor. Other known loads can be driven via the low-pressure turbine. The fuel can be in gaseous and / or liquid form.

[0039] Reference Figure 1 The turbine engine 10 shown and described is merely one example of many engines or turbomachinery into which the present invention can be incorporated. Such engines can be gas turbines or steam turbines, and include single-shaft, twin-shaft, and triple-shaft engines used in marine, industrial, and aerospace applications.

[0040] Figure 2 This is a cross-section through a portion of the combustor 36 of the turbine engine 10 described above and according to the invention. The radial vortex 40 comprises an annular array of blades 46 angled tangentially relative to the combustor axis 44 to generate a vortex flow 55 of mixed air and fuel, as is known. The vortex flow 55 rotates about the combustor axis 44 and flows in a generally left-to-right direction, as... Figure 2As seen in the cross-section. Swirl impellers 46 form an array of mixing channels or swirl slots 47 between each successive swirl impeller 46. Swirl 46 also includes main fuel injectors 48A, 48B for injecting main fuel and an ignition fuel injector 50 for injecting ignition fuel. Swirl 40 includes a base plate 45 having a guide surface 52 facing the pre-combustion chamber 42 and defining an upstream axial extent of the pre-combustion chamber. The pre-combustion chamber 42 is further defined by an annular wall 54 having parallel sides as shown in the cross-section. The pre-combustion chamber 42 has an inlet 66 and an outlet 68. The outlet 68 is formed at or located at the lip 69 of the pre-combustion chamber 42 and defines the termination position of the pre-combustion chamber 42. Following the annular wall 54 of the pre-combustion chamber 42 is a generally annular wall 37 of the main combustion chamber 38. Downstream from the lip 69, the generally annular wall 37 is divergent and open to define the main combustion chamber 38. The main combustion chamber 38 has a cross-sectional area that is larger than that of the pre-combustion chamber 42.

[0041] Two distinct fuel / air mixtures and subsequent combustion flames exist within combustion chamber 38; the ignition flame 56 originates from the ignition fuel / air mixture, while the main flame 58 originates from the main fuel / air mixture. The ignition flame 56 and the main flame 58 differ from each other due to the location of their respective fuel injection points within or near the mixing channel 47 in the airflow 34A. The main fuel injectors 48A and 48B inject main fuel into the swirler slots or mixing channel 47, and are located further away from the burner axis 44, i.e., radially outside the burner axis 44, compared to the ignition fuel injector 50. Therefore, the corresponding fuel / air mixtures form significantly different flame regions, with the ignition flame 56 typically located radially inside the main flame 58.

[0042] As in the case here, a radial cyclone has, or can be defined as having, a swirl number SN. As is known in the art, the swirl number can be calculated, and here it can be said that the swirl number can be defined by the relationship between the angular momentum flux and the linear momentum flux of the fuel / air mixture. That is, the angular momentum is related to the rotational velocity about the combustor axis 44, while the linear momentum is related to the velocity in the axial direction along the combustor axis 44. Therefore, SN is defined herein as the ratio of the tangential momentum to the axial momentum of the fluid or fuel / air mixture.

[0043] Figure 2A schematic cross-section of the overall diagram shows a dry low-emission (DLE) burner 36. The aforementioned known radial swirler 40 has a SN in the range of 0.5 to 0.8. This burner provides a good DLE burner for burning methane and medium-calorific-value fuels (MCV fuels) containing hydrocarbons. However, this current design is not suitable for burning fuels with a large amount (e.g., >5%, by weight) of hydrogen or high hydrocarbon content, primarily due to the dominance of significantly higher flame velocities on flow characteristics. The presence of hydrogen or high hydrocarbons in the fuel increases the flame velocity and causes backfire into the pre-combustion chamber 42. This is obviously harmful and undesirable and can lead to flameout and increased emissions of nitrogen oxides, sulfur oxides, unburned hydrocarbons, and other undesirable combustion byproducts.

[0044] The burner 36 includes a premixer nozzle 70 located on the wall 37 of the combustion chamber 38. As shown in this example, the burner 36 includes a first fuel supply line 72 and a second fuel supply line 74, and valves 73 and 75 respectively located on the first fuel supply line 72 and the second fuel supply line 74. Each of valves 73 and 75 is connected to a controller 76. The controller 76 may be part of an electronic control unit for a gas turbine engine. Valves 73 and 75 can be independently controlled and can be independently controlled between opening and closing to change the amount of fuel flowing through them and to the premixer nozzle 70. Valves 73 and 75 (and referred to later) Figure 4 The valve 99 described can operate independently or in open-loop or closed-loop configurations to control emissions, performance, and engine output.

[0045] Although Figure 2 Only one premixer nozzle 70 is shown, but the exemplary combustion chamber 36 includes an array of premixer nozzles 70. In one example, there are four premixer nozzles 70, and the four premixer nozzles 70 are evenly spaced around the circumference of the combustion chamber 36. In other examples, there may be up to eight premixer nozzles, and eight premixer nozzles may be included. All the premixer nozzles 70 are located in the same axial position relative to the burner axis 44; however, in other examples, there may be two or more axial positions, such that the alternating premixer nozzles 70 are axially offset from each other in a circumferential sequence.

[0046] Figure 3A partial cross-sectional view of a premixer nozzle 70 is shown. The premixer nozzle 70 includes a housing 78 and an array of tubes 80 within the housing 78. The housing 78 is conventionally attached to the burner wall 37, for example, by welding. The array of tubes 80 has a centerline 89, which is typically radially inwardly aligned at the burner axis 44. In other embodiments, the centerline 89 may be axially angled relative to an axial line (i.e., away from the radial line) and / or tangentially angled in either direction.

[0047] Each tube 80 in the array of tubes 80 includes an inlet 86 located at a radially outer portion of the premixer nozzle 70 and an outlet 88 located at a radially inner portion of the premixer nozzle 70. Each tube 80 has a first orifice 90 and a second orifice 92. The orifices 90 and 92 are positioned closer to the inlet 86 than the outlet 88. The premixer nozzle 70 has a first fuel passage 72 for supplying a first fuel 83 and a second fuel passage 74 for supplying a second fuel 85.

[0048] The premixer nozzle 70 is formed by additive manufacturing processes such as laser deposition, and thus the complex configuration of the array of tubes 80 and fuel channels 72, 74 can be easily formed into an integral structure.

[0049] In operation, air 34 is supplied to the burner 36, with a first portion of air 34A passing through a radial vortex 40, and a second portion of air 34B passing through tubes 80 in an array of tubes 80 in a direction from inlet 86 to outlet 88, and this direction being generally radially inward toward the burner axis 44. Air 34B is mixed with first fuel 83 passing through a first orifice 90 and second fuel 85 passing through a second orifice 92 of each tube 80. The air and fuel are mixed together in the tubes 80 before being injected through outlet 88 and entering the combustion chamber 38.

[0050] Figure 4 Is it like this? Figure 3 The cross-section SA-SA of the premixer nozzle 70 is shown. An example of the arrangement of the tube array 80 can be seen here. The tubes 80 are tightly packed together such that the diagonal rows are offset from each other in a manner centered on the body. Alternatively, in a manner as... Figure 3 The cross-section of the premixer nozzle 70 seen is SA-SA. Figure 5In this configuration, tubes 80 are arranged around the outer periphery of housing 78, but inside housing 78. In both examples, at least one tube 80A does not have a first orifice 90 or a second orifice 92. This tube 80A is located at the center of the array of tubes 80. However, not only can there be other tubes 80A, but tubes 80A can also be positioned off-center. For this tube 80A, only air 34B passes through it. The primary purpose of tube 80A is to supply air 34B solely and directly from the supply device to provide sufficient oxygen to burn off any CO that the premixer nozzle 70 may produce at or around outlet 88. Furthermore, tube 80A ensures that the premixer nozzle 70 has a certain amount of air to mix with the fuel-air mixture discharged from other tubes 80, and this enhances, for example, air-assisted characteristics to change the local equivalence ratio and thus the flame temperature. In another example, a third fuel 97 can be supplied via a third fuel supply device 98. The third fuel supply device 98 includes a valve 99 for changing the amount of the third fuel 97. Valve 99 is controllable via controller 76. Preferably, the third fuel 97 is a liquid fuel, but it can also be a gaseous fuel. Pipe 80A can have a larger cross-sectional area than the other pipes 80.

[0051] Figure 6 This is an enlarged view of one of the tubes 80 in an array of tubes 80 of the premixer nozzle 70. The tube 80 has a converging portion 102 that converges toward an outlet 88. The tube 80 has a substantially constant cross-sectional area portion 100 located radially outside the converging portion 102. The substantially constant cross-sectional area portion 100 is arranged parallel to or approximately parallel to the centerline 89. The converging portion 102 is angled toward the centerline 89 relative to the direction of the gas flow through it, or considered as a direction from the inlet 86 toward the outlet 88. A first orifice 90 and a second orifice 92 are located within the portion 100. However, in other embodiments, the first orifice 90 and / or the second orifice 92 may be located within the converging portion 102. Furthermore, the entire tube 80 can converge from the inlet 86 to the outlet 88. The converging portion 102 has a cross-sectional area, and the cross-sectional area of ​​the converging portion 102 decreases by between 10% and 40% toward the outlet of the tube 80. Figure 6 and Figure 8Cross-sectional areas A1 and A2 are shown. Area A1 is upstream of area A2. The percentage change in area (e.g., between A1 and A2) depends at least in part on the fuel composition used. The higher the hydrogen content and / or the more hydrocarbon-based the fuel, the greater the required reduction in cross-sectional area. A greater percentage reduction in cross-sectional area means a correspondingly increased velocity of fuel exiting from pipe 80. Preferably, the reduction in cross-sectional area from cross-section A1 to cross-section A2 of pipe 80 falls within the range of 10% to 40% of the cross-sectional area of ​​cross-section A1. It should be noted that all pipes may have the same reduction in cross-sectional area, or some pipes of pipe 80 may have a different reduction in cross-sectional area than the others. The reduction in cross-sectional area of ​​each pipe 80 may further be based on the number of premixer nozzles 70 and the number of pipes 80 that each premixer nozzle 70 has. Any specific design of the premixer nozzle 70—including convergence rate, fuel and air pressure, and combustion chamber pressure—should cause the fuel and air mixture to exit the pipe outlet 88 at a speed between 60 m / s and 100 m / s, and inclusive.

[0052] One of the first orifice 90 and the second orifice 92 is located radially outside the other, and in this example, the second orifice 92 is located radially outside the first orifice 90. Second fuel 85 is injected as a jet into pipe 80, where it impacts air 34B and begins to mix. Then, first fuel 83 is injected into the air-fuel mixture, further generating turbulence to enhance fuel-air mixing. Fuel with a higher hydrocarbon content is injected as first fuel 83 from the first orifice 90, while lighter fuels, such as those with a hydrogen content, are injected as second fuel 85 from the second orifice 92. One reason for this is that heavier hydrocarbon-based fuels require a longer residence time in pipe 80 to mix with air compared to lighter fuels, such as those with a hydrogen content. The first orifice 90 and the second orifice 92 are offset from each other relative to the direction of air flow 34B. The advantage of this design is that the two fuel jets impact each other to enhance turbulence, and thus enhance air-fuel mixing before being injected into combustion chamber 38. Therefore, the two orifices 90 and 92 should be positioned accordingly, and preferably within twice the cross-sectional width (or diameter) of the tube 80.

[0053] Figure 7 This is a schematic cross-section through the premixer nozzle 70 of the currently disclosed second embodiment. Here, in conjunction with reference to... Figure 3 Compared to the first embodiment of the premixer nozzle 70, the second channel 84, the second fuel supply line 74, and the valve 75 are omitted. Other features are similar to the first embodiment and will not be described further.

[0054] The first fuel passage 82 is arranged to supply first fuel 83 to a first orifice 90 and a second orifice 92 in each tube 80. In other words, the first orifice 90 and the second orifice 92 are located within the first fuel passage 82. In use, air 34 is supplied to the burner 36, and a first portion of air 34A passes through a cyclone separator, while a second portion of air passes from inlet 86 through tubes 80 in the array of tubes 80 to outlet 88 and mixes with the first fuel 83 passing through the first orifice 90 and the second orifice 92.

[0055] Figure 8 This is an enlarged view of an alternative embodiment of an array of tubes 80 in the second embodiment of the premixer nozzle 70. Figure 6 Compared to the previous embodiment, similar features are given similar reference numerals and will not be described further. In this second embodiment, the first orifice 90 and the second orifice 92 are aligned with each other across the tube 80. That is, the first orifice 90 and the second orifice 92 guide the jet of the first fuel 83 to collide with each other approximately at the center of the tube 80. The collision of the two fuel jets generates turbulence and enhances mixing with the air 34B, which is highly desirable.

[0056] For the first and second embodiments of the premixer nozzle 70, fuel exits from at least one of the orifices 90 and 92, preferably at a speed between 50 m / s and 80 m / s, and including both. The orifices 90 and 92 are sized accordingly, taking into account the viscosity and density of the fuel type and the pressure of the fuel supply. Therefore, one of the orifices 90 and 92 may have a different outlet area than the other. Once mixed with air 34B, the fuel and air mixture exits from the pipe outlet 88 at a speed between 60 m / s and 100 m / s, and including both.

[0057] All features disclosed in this application (including any appended claims, abstract, and drawings) and / or all steps of any method or process disclosed thereby may be combined in any combination except for combinations in which at least some of such features and / or steps are mutually exclusive.

[0058] Each feature disclosed in this application (including any appended claims, abstract, and drawings) may be replaced by an alternative feature for the same, equivalent, or similar purpose, unless otherwise expressly stated. Therefore, unless otherwise expressly stated, each disclosed feature is merely one example of an equivalent or similar feature in a similar series.

[0059] This invention is not limited to the details of the foregoing embodiments. The invention extends to any novel feature or combination of novel features disclosed in this application (including any appended claims, abstract, and drawings), or to any novel method or process step or combination of novel method or process steps disclosed thereby.

Claims

1. A combustor (36) for a gas turbine, the combustor (36) comprising a combustor axis (44), about which are arranged in a flow sequence: Radial cyclone (40). Pre-combustion chamber (42), and Combustion chamber (38) The radial cyclone (40) includes: base plate (45), A ring array of hydrocyclone blades (46) defines a hydrocyclone groove (47) arranged around the substrate (45). Main fuel injectors (48A, 48B), said main fuel injectors (48A, 48B) are used to inject main fuel, and Ignition fuel injector (50), said ignition fuel injector (50) is used to inject ignition fuel, The burner also includes: A premixer nozzle (70) is located on the combustion chamber (38), the premixer nozzle comprising a radially outer portion and a radially inner portion in the radial direction of the combustion chamber, the premixer nozzle (70) comprising: Shell (78) An array of tubes (80), the array of tubes (80) being located within the housing (78), The first fuel passage (72) is used to supply the first fuel (83), and The second fuel passage (74) is used to supply the second fuel (85). Each tube (80) in the array of tubes (80) includes: Inlet (86), the inlet being located at the radially outer portion of the premixer nozzle, Outlet (88), the outlet being located at the radially inner portion of the premixer nozzle. First orifice (90), and A second orifice (92), wherein the first orifice and the second orifice are arranged transversely to the pipe, and the first orifice (90) and the second orifice (92) of each pipe in the array of pipes (80) are respectively arranged relatively closer to the inlet (86) than the outlet (88), wherein the inlet (86) of each pipe in the array of pipes (80) is fluidly connected to receive compressed air from a compressor connected to the gas turbine. The first fuel passage (72) is arranged to supply the first fuel (83) to the first orifice (90), and the second fuel passage (74) is arranged to supply the second fuel (85) to the second orifice (92). In use, a first portion (34A) of the compressed air is arranged to pass through the radial vortex (40) to be delivered directly from the pre-combustion chamber (42) to the combustion chamber (38), while a second portion (34B) of the compressed air is delivered directly to the premixer nozzle (70) to pass from the inlet (86) through the tubes (80) in the array of tubes (80) to the outlet (88), wherein, as the second portion (34B) of the compressed air travels from the inlet (86) of each tube in the array of tubes (80) within the housing (78) of the premixer nozzle (70) to the outlet (88), the second portion (34B) of the compressed air is mixed with the first fuel (83) and the second fuel (85).

2. The burner (36) according to claim 1, wherein, At least one of the tubes (80) in the array of tubes (80) includes a converging portion (102) that converges toward the outlet (88).

3. The burner (36) according to claim 2, wherein, The converging portion (102) has a first cross-sectional area (A1) and a second cross-sectional area (A2), the second cross-sectional area (A2) being downstream of the first cross-sectional area (A1), and The reduction in cross-sectional area between the first cross-sectional area (A1) and the second cross-sectional area (A2) falls within the range of 10% to 40% of the first cross-sectional area (A1).

4. The burner (36) according to any one of claims 1 to 3, wherein, The fuel and air mixture exits the outlet (88) of the pipe (80) at a speed between 60 m / s and 100 m / s, including 60 m / s and 100 m / s.

5. The burner (36) according to any one of claims 1 to 3, wherein, The first fuel (83) and / or the second fuel (85) exit at least one of the first orifice (90) and the second orifice (92) at a speed between 50 m / s and 80 m / s and including 50 m / s and 80 m / s and enter the pipe (80).

6. The burner (36) according to any one of claims 1 to 3, wherein, The first orifice (90) and the second orifice (92) span the tube (80) and face each other, so that the corresponding jets of the first fuel (83) and the second fuel (85) collide with each other.

7. The burner (36) according to claim 6, wherein, The first orifice (90) and the second orifice (92) span the tube (80) and are directly opposite and aligned with each other.

8. The burner (36) according to any one of claims 1 to 3, wherein, The first orifice (90) and the second orifice (92) have different areas.

9. The burner (36) according to any one of claims 1 to 3, wherein, At least one tube (80A) does not have a first orifice (90) or a second orifice (92).

10. The burner (36) according to claim 9, wherein, The at least one pipe (80A) has a third fuel supply device (98) for supplying third fuel (97).

11. The burner (36) according to any one of claims 1 to 3, wherein, The first fuel (83) and / or the second fuel (85) is any one or a combination of natural gas, hydrogen, and liquefied petroleum gas.

12. The burner (36) according to any one of claims 1 to 3, wherein, The combustion chamber (38) includes an array of premixer nozzles (70) having between 4 and 8 nozzles, and including both 4 and 8 premixer nozzles (70).

13. The burner (36) according to claim 12, wherein, The premixer nozzles (70) are evenly spaced around the circumference of the combustion chamber (38).

14. The burner (36) according to claim 12, wherein, The premixer nozzles (70) are arranged such that some of the premixer nozzles (70) are axially offset relative to the other premixer nozzles (70).

15. The burner (36) according to claim 10, wherein, Any or more of the main fuel, the ignition fuel, the first fuel, the second fuel, and the third fuel are each supplied via fuel supply lines (72, 74, 98) and valves (73, 75, 99). The valves (73, 75, 99) are controllable and connected to the controller (76). The controller (76) is configured to change the amount of any one or more of the main fuel, the ignition fuel, the first fuel, the second fuel, and the third fuel individually, jointly, or simultaneously.

16. The burner (36) according to claim 2, wherein, The converging portion (102) terminates at the outlet (88).

17. The burner (36) according to claim 9, wherein, The central tube (80A) does not have a first orifice (90) or a second orifice (92).

18. The burner (36) according to claim 10, wherein, The third fuel (97) is a liquid fuel.

19. A method of injecting fuel into a burner (36) according to any one of claims 1 to 18, wherein, The method includes at least one of the following steps: Fuel is injected from at least one of the first orifice (90) and the second orifice (92) at a speed between 50 m / s and 80 m / s, and including 50 m / s and 80 m / s, into at least one of the pipes (80). A fuel and air mixture is injected from the outlet (88) of at least one of the pipes (80) at a speed between 60 m / s and 100 m / s, and including 60 m / s and 100 m / s.

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