Gas turbine and nozzle thereof

Abstract

The utility model discloses a gas turbine and a nozzle thereof, and relates to the technical field of gas turbines. The nozzle comprises a first premixing spray pipe and a second premixing spray pipe, the first air flow channel and the first premixing flow channel are sequentially arranged in the first premixing spray pipe; the first air flow channel is used for guiding air to the first premixing flow channel; the first premixing flow channel is used for mixing air and fuel to form mixed gas and guiding the mixed gas to the combustion chamber. The inner diameter of the first premixing runner in the first direction is gradually reduced; and the fuel spray rod is used for guiding fuel to the first premixing flow channel. According to the nozzle, the inner diameter of the first premixing flow channel in the first direction (namely the flowing direction of mixed gas) is gradually decreased, and therefore the flowing speed of the mixed gas is increased after the mixed gas passes through the first premixing flow channel. That is to say, the nozzle can increase the flowing speed of the mixed gas so as to reduce the tempering probability of the combustion chamber.

Description

Technical Field

[0001] The present application relates to the technical field of gas turbines, and in particular to a gas turbine and a nozzle thereof. Background Art

[0002] With the increase of environmental awareness, the demand for low-emission gas turbines is also increasing. In the prior art, lean premixed combustion technology is often used to reduce the emission of pollutants when the gas turbine is working. Lean premixed combustion technology refers to the technology of pre-mixing the fuel and air relatively evenly to form a mixture, and then injecting the mixture into the main combustion zone for combustion. Generally, the nozzles based on lean premixed combustion technology are tubular structures, and the nozzles with tubular structures are prone to combustion chamber flashback in their terminal wake or low-speed area. If the combustion chamber flashes back, the various components in the combustion chamber or the parts in the nozzle will suffer high-temperature corrosion, potentially causing serious damage to the entire combustion chamber, causing systemic failures, and causing large economic losses. With the development of fuel diversification, the scenarios for the use of medium and low calorific value fuels are gradually increasing, and the combustion speed of medium and low calorific value fuels is relatively fast, which further aggravates the phenomenon of flashback in the combustion chamber. Utility Model Content

[0003] The purpose of the present application is to provide a gas turbine and a nozzle thereof, so as to solve the technical problem in the prior art that the nozzle is prone to combustion chamber flashback.

[0004] To achieve the above objectives, this application provides the following technical solutions:

[0005] In a first aspect, the present application provides a nozzle for use in a gas turbine, wherein the gas turbine comprises a combustion chamber, and the nozzle comprises:

[0006] A first premixing nozzle;

[0007] A first air flow channel and a first premixing flow channel are sequentially arranged inside the first premixing nozzle; the first air flow channel is used to guide air to the first premixing flow channel; the first premixing flow channel is used to mix air and fuel to form a mixed gas, and is used to guide the mixed gas to the combustion chamber; the inner diameter of the first premixing flow channel decreases along a first direction, the first direction is parallel to the axis of the first premixing nozzle, and points from the head end to the end of the first premixing nozzle;

[0008] A fuel spray rod is used to guide the fuel to the first premixing flow channel.

[0009] As a specific solution in the technical solution of the present application, the fuel nozzle rod is located inside the first premixing nozzle, and the axis center lines of the fuel nozzle rod and the first premixing nozzle coincide with each other, the end of the fuel nozzle rod extends to the inside of the first premixing flow channel, and the end wall of the fuel nozzle rod is provided with a plurality of first spray holes.

[0010] As a specific solution in the technical solution of the present application, the end wall is in the shape of a hollow sphere, and the first spray holes are evenly distributed on the end wall.

[0011] As a specific solution in the technical solution of the present application, the side wall of the first premixing nozzle is provided with a plurality of air through holes, and each of the air through holes is in a long strip shape.

[0012] As a specific solution in the technical solution of the present application, a first swirler is arranged in the first air flow channel.

[0013] As a specific solution in the technical solution of this application, it also includes:

[0014] A second premixing nozzle is sleeved on the outside of the first premixing nozzle, and a second premixing flow channel is provided between the second premixing nozzle and the first premixing nozzle;

[0015] A plurality of support rods are evenly distributed around the circumference of the first premixing nozzle, and one end of each support rod is connected to the inner wall of the second premixing nozzle; the other end of each support rod is connected to the outer wall of the first premixing nozzle.

[0016] As a specific solution in the technical solution of the present application, the interior of the first premixing nozzle is provided with fuel flow channels corresponding to multiple support rods one by one, and each fuel flow channel extends into the corresponding support rod; each support rod is provided with multiple second spray holes, and the second spray holes are used to connect the fuel flow channel and the second premixing flow channel.

[0017] As a specific solution in the technical solution of the present application, the inner diameter of each second nozzle increases gradually along the second direction, the second direction is parallel to the radial direction of the first premixing nozzle, and points from the inside to the outside of the first premixing nozzle.

[0018] As a specific solution in the technical solution of the present application, the interior of the first premixing nozzle is provided with second air flow channels corresponding to multiple support rods one by one; each second air flow channel extends to the interior of the corresponding support rod and passes through the second premixing nozzle.

[0019] In a second aspect, the present application proposes a gas turbine, comprising a nozzle as described in any one of the first aspects.

[0020] Compared with the prior art, the beneficial effects of this application are:

[0021] The inner diameter of the first premixing flow channel in the nozzle decreases along the first direction (i.e., the flow direction of the mixed gas), so the flow velocity of the mixed gas increases after passing through the first premixing flow channel. In other words, the nozzle can increase the flow velocity of the mixed gas to reduce the probability of backfire in the combustion chamber. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 A cross-sectional view of a nozzle proposed in an embodiment of the present application;

[0023] Figure 2 A three-dimensional diagram of another nozzle proposed in an embodiment of the present application;

[0024] Figure 3 for Figure 2 A perspective view without the second premixing nozzle;

[0025] Figure 4 for Figure 2 A cross-sectional view of

[0026] Figure 5 A schematic diagram of the fluid flow route proposed in the embodiment of the present application;

[0027] Figure 6 A cross-sectional view of a fuel spray bar proposed in an embodiment of the present application;

[0028] Figure 7 A cross-sectional view of another fuel spray bar proposed in an embodiment of the present application;

[0029] Figure 8 for Figure 7 Cross-sectional view of the fuel spray boom along line aa.

[0030] In the figure: 1, second premixing nozzle; 11, second air flow channel; 2, first premixing nozzle; 21, air through hole; 22, fuel flow channel; 23, fourth nozzle hole; 24, third nozzle hole; 3, fuel nozzle rod; 36, end wall; 37, first nozzle hole; 38, hole axis; 4, first air flow channel; 5, first swirler; 6, first premixing flow channel; 7, second premixing flow channel; 8, support rod; 81, second nozzle hole; 9, second swirler. DETAILED DESCRIPTION

[0031] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0032] It should be noted that, in the description of the present application, the terms "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description. They do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore should not be understood as a limitation on the present application.

[0033] Furthermore, it should be understood that for the sake of ease of description, the sizes of the various components shown in the drawings are not drawn according to actual proportions. For example, the thickness or width of certain layers may be exaggerated relative to other layers.

[0034] It should be noted that like reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined or described in one drawing, it will not require further detailed discussion and description in the description of the subsequent drawings.

[0035] The embodiment of the present application provides a nozzle, which is applied to a gas turbine, and the gas turbine includes a combustion chamber. Since the gas turbine with a combustion chamber belongs to the mature prior art, the gas turbine and the combustion chamber are not described in detail in the embodiment of the present application. Specifically, Figure 1 and Figure 4 As shown, the nozzle includes a first premixing nozzle 2 and a fuel nozzle rod 3. The first air flow channel 4 and the first premixing flow channel 6 are sequentially arranged inside the first premixing nozzle 2 according to the flow direction of the fluid. Specifically, the first air flow channel 4 is used to guide air to the first premixing flow channel 6; the fuel nozzle rod 3 is used to guide fuel to the first premixing flow channel 6; and the first premixing flow channel 6 is used to mix the air from the first premixing flow channel 6 and the fuel from the fuel nozzle rod 3 to form a mixed gas, and is used to guide the mixed gas to the combustion chamber for combustion.

[0036] Specifically, in the embodiment of the present application, the first air flow channel 4 is used to guide air to the first premixing flow channel 6; the fuel nozzle 3 is used to guide fuel to the first premixing flow channel 6. That is to say, in the embodiment of the present application, it is only necessary for the first air flow channel 4 and the fuel nozzle 3 to have a fluid guiding function, and there is no restriction on the shape and structure of the first air flow channel 4 and the fuel nozzle 3. Figure 1 and Figure 4 As shown, the first air flow channel 4 may be a fluid channel disposed inside the first premixing nozzle 2; Figure 1 , Figure 4 and Figure 6As shown, the fuel spray rod 3 may be a tubular rod. It is easy to understand that in other embodiments of the present application, the fuel spray rod 3 may be integrally formed with the first premixing nozzle 2, and a fuel flow channel is formed inside the fuel spray rod 3; the first air flow channel 4 may also be formed inside the tubular rod.

[0037] In order to solve the technical problems in the background technology, in the embodiment of the present application, the inner diameter of the first premixing channel 6 decreases along the first direction, the first direction is parallel to the axis of the first premixing nozzle 2, and is pointed from the head end of the first premixing nozzle 2 to the end. Specifically, in the present application, the components or structures used to guide the fluid in the nozzle (for example: the first premixing nozzle 2, the second premixing nozzle 1 or the first premixing channel 6, etc.) are defined as the head end and the end end, wherein the head end refers to the end where the fluid flows into the component or structure, and the end end refers to the end where the fluid flows out of the component or structure. That is to say, in the nozzle proposed in the embodiment of the present application, the flow direction of the fluid is always from the head end of a certain component or structure to the end. In the embodiment of the present application, the fluid refers to air, fuel, or a mixture formed by a mixture of air and fuel.

[0038] Specifically, Figure 1 and Figure 4 As shown, since the inner diameter of the first premixing flow channel 6 proposed in the embodiment of the present application decreases along the first direction (that is, the flow direction of the mixed gas), the flow channel area of ​​the first premixing flow channel 6 gradually decreases along the flow direction of the mixed gas. It is easy to understand that during the flow of the fluid, if the flow channel area decreases, the flow velocity of the fluid increases. In other words, if the inner diameter of the first premixing flow channel 6 decreases along the first direction, the flow velocity of the mixed gas ejected from the end of the first premixing flow channel 6 increases (that is, the mixed gas ejected into the combustion chamber); if the flow velocity of the mixed gas ejected into the combustion chamber increases, the probability of backfire in the combustion chamber can be reduced, or the severity of backfire in the combustion chamber can be reduced.

[0039] It should be clear that in lean premixed combustion technology, the uniformity of air and fuel mixing can have a direct impact on the pollutants produced after combustion. If the air and fuel are mixed evenly, the pollutants produced after the mixture is burned can be reduced. If the air and fuel are mixed evenly, the pollutants produced after the mixture is burned can be increased.

[0040] In the embodiment of the present application, in order to improve the uniformity of mixing of air and fuel. Figure 1 and Figure 4 As shown, the fuel nozzle rod 3 is located inside the first premixing nozzle 2, and the axis of the fuel nozzle rod 3 coincides with the axis of the first premixing nozzle 2, and the end of the fuel nozzle rod 3 extends to the inside of the first premixing channel 6. Figure 1 and Figure 4It can be seen that, since the fuel nozzle rod 3 is sleeved inside the first air flow channel 4 , the air sprayed from the first air flow channel 4 and the fuel sprayed from the fuel nozzle rod 3 can be uniformly mixed along the circumferential direction of the first premixing flow channel 6 .

[0041] It should be understood that, in the embodiment of the present application, an opening (not shown) may be provided at the end of the fuel spray bar 3, and the fuel inside the fuel spray bar 3 may enter the first premixing channel 6 through the opening. In order to further evenly mix the air and fuel in the first premixing channel 6, as shown in FIG. Figure 6 As shown, the end of the fuel spray rod 3 is formed with an end wall 36, and a plurality of first spray holes 37 are provided on the end wall 36. That is, the fuel inside the fuel spray rod 3 can be sprayed out in the form of a plurality of fuel beams through the plurality of first spray holes 37. Compared with the fuel sprayed from a single opening, the plurality of fuel beams sprayed from the plurality of first spray holes 37 can be mixed with the air more evenly.

[0042] In one embodiment of the present application, in order to further uniformly mix the air and fuel in the first premixing flow channel 6, as shown in FIG. Figure 7 As shown, the end wall 36 of the fuel spray rod 3 can be designed to be a hollow sphere, and each first spray hole 37 is evenly distributed on the end wall 36. Since the end wall 36 is spherical, each first spray hole 37 evenly distributed on the end wall 36 can spray fuel beams from various directions. Compared with being able to spray multiple fuel beams from only one direction, the fuel beams sprayed from various directions are more conducive to being evenly mixed with air to form a mixed gas.

[0043] In one embodiment of the present application, in order to further uniformly mix the air and fuel in the first premixing flow channel 6, as shown in FIG. Figure 8 As shown, along the axis direction of the fuel spray rod 3, the first spray holes 37 at the same height are arranged in an array around the axis of the fuel spray rod 3, and the axis of each first spray hole 37 (i.e. Figure 8 The hole axis 38 in the nozzle 3 is a non-planar straight line with the axis of the fuel nozzle rod 3. It should be clear that after the fluid is ejected from the hole, the flow direction of the fluid is parallel to the axis of the hole. That is to say, in this embodiment, since the axis of each first nozzle hole 37 is a non-planar straight line with the axis of the fuel nozzle rod 3, the fuel ejected from each first nozzle hole 37 can form a swirl around the axis of the fuel nozzle rod 3, and the swirl fuel can be evenly mixed with the air.

[0044] In an embodiment of the present application, a hole (not shown in the figure) can be directly opened at the head end of the first premixing nozzle 2, so that the air outside the first premixing nozzle 2 can enter the first air flow channel 4 based on the hole to participate in subsequent combustion. It should be understood that in the process of uniformly mixing the fuel and the air to form a mixed gas, if the air flow rate along the axial direction of the first premixing nozzle 2 is too fast, the air will continue to flow forward along the radial direction of the first premixing nozzle 2 before being mixed with the fuel, which is likely to cause uneven mixing of the air and the fuel in the first premixing flow channel 6. In order to avoid the air speed entering the first air flow channel 4 being too fast, such as Figure 1 and Figure 4 As shown in FIG. 1 , the side wall of the first premixing nozzle 2 is provided with a plurality of air through holes 21. The air flow path outside the first premixing nozzle 2 is as follows: Figure 5 As shown in the route A in FIG. 1 , the flow path of the air outside the first premixing nozzle 2 entering the first air flow channel 4 is as shown in FIG. Figure 5 As shown in the route C in FIG. Compared with the opening at the head end of the first premixing nozzle 2, the air through hole 21 is provided on the side wall of the first premixing nozzle 2, so that the air outside the first premixing nozzle 2 can enter the first air flow channel 4 after being turned. It is easy to understand that if the air is turned, the flow rate of the air is slowed down, that is, the air with a lower flow rate can be mixed with the fuel in the first premixing flow channel 6 more evenly.

[0045] Specifically, in the embodiments of the present application, in order to more clearly show the flow paths of each fluid, Figure 5 The light blue lines in the figure represent the flow paths of the various fluids.

[0046] It should be clear that in the embodiment of the present application, there is no restriction on the shape and structure of the air hole 21. For example, the air hole 21 can be circular, triangular or square. It is easy to understand that since the space on the first premixing nozzle 2 is limited, the amount of air entering the first air flow channel 4 from the first premixing nozzle 2 is positively correlated with the cross-sectional area of ​​the air hole 21. In order to ensure that the amount of air entering the first air flow channel 4 can meet the design requirements, in one embodiment of the present application, Figures 1 to 3 As shown, each air through hole 21 is in the shape of an elongated strip. The elongated air through hole 21 can form a sufficiently large cross-sectional area in a limited space so that the amount of air entering the first air flow channel 4 can meet the design requirements. Specifically, in the embodiment of the present application, each air through hole 21 can be evenly distributed around the circumference of the first premixing nozzle 2, and each air through hole 21 can extend in a direction parallel to the axis of the first premixing nozzle 2.

[0047] It should be clear that in order to make the air ejected from the first air flow channel 4 and the fuel in the first premixing flow channel 6 more evenly mixed. Figure 1 and Figure 4 As shown, a first swirler 5 is provided in the first air flow channel 4. Specifically, firstly, the first swirler 5 can reduce the flow velocity of the air in the first air flow channel 4, that is, the reduced-speed air can be mixed with the fuel more evenly, and secondly, the first swirler 5 can form a swirl of the air in the first air flow channel 4, and the axial velocity of the swirl air is reduced and the tangential velocity is increased; the air with increased tangential velocity is more conducive to mixing with the fuel.

[0048] It should be clear that the amount of the generated mixed gas needs to be changed accordingly during the power change process of the gas turbine. For example: if the power of the gas turbine is reduced, the amount of the generated mixed gas needs to be reduced; if the power of the gas turbine is increased, the amount of the generated mixed gas needs to be increased. It is easy to understand that in the embodiment of the present application, the mixed gas is mainly formed by mixing the air and fuel in the first premixing flow channel 6. Since the flow channel area of ​​the first premixing flow channel 6 is fixed, if the amount of the mixed gas is to be increased, the flow rate of the mixed gas needs to be increased, that is, the supply pressure of the air and fuel needs to be increased; if the amount of the mixed gas is to be reduced, the flow rate of the mixed gas needs to be reduced, that is, the supply pressure of the air and fuel needs to be reduced. It should be clear that if the flow rate of the mixture is reduced during the stable operation of the gas turbine, combustion chamber backfire is likely to occur; if only the fuel supply pressure is reduced, and the air supply pressure is not reduced to maintain the flow rate of the mixture, it is likely to cause the proportion of fuel in the mixture to be smaller and cause the gas turbine to stall; if only the air supply pressure is reduced, and the fuel supply pressure is not reduced to maintain the flow rate of the mixture, it is likely to cause the proportion of fuel in the mixture to be larger and cause an increase in pollutants generated by combustion.

[0049] In order to reduce the occurrence of combustion chamber flashback during the power change of the gas turbine and maintain the low pollutant emission performance of the gas turbine. In one embodiment of the present application, Figure 4 As shown, the nozzle may also include a second premixing nozzle 1 and a plurality of support rods 8. Among them, the second premixing nozzle 1 is sleeved on the outside of the first premixing nozzle 2, and a second premixing flow channel 7 is arranged between the second premixing nozzle 1 and the first premixing nozzle 2. It is easy to understand that the second premixing flow channel 7 has a similar function to the first premixing flow channel 6 mentioned above, which is mainly used for air and fuel to form a mixed gas inside it, and guide the mixed gas to the combustion chamber to participate in combustion. One end of each support rod 8 is connected to the inner wall of the second premixing nozzle 1; the other end of each support rod 8 is connected to the outer wall of the first premixing nozzle 2. The function of the support rod 8 is to form a stable connection between the first premixing nozzle 2 and the second premixing nozzle 1, that is, to make the second premixing flow channel 7 stable. In the embodiment of the present application, there is no limitation on the position of each support rod 8. In order to facilitate the use of the support rod 8 in conjunction with the second air flow channel 11 and the fuel flow channel 22 described below, each support rod 8 can be evenly distributed around the circumference of the first premixing nozzle 2.

[0050] Specifically, in this embodiment, if the power of the gas turbine increases, the second premixing flow channel 7 can be used to mix and form a mixed gas to increase the amount of the mixed gas produced; if the power of the gas turbine decreases, the amount of the mixed gas mixed and formed by the second premixing flow channel 7 can be first reduced. Compared with the method of changing the total amount of the mixed gas by changing the flow rate of the mixed gas in the first premixing flow channel 6 in the prior art, the embodiment of the present application can keep the flow rate and composition of the mixed gas in the first premixing flow channel 6 unchanged, that is, the embodiment of the present application can reduce the occurrence of the flashback phenomenon in the combustion chamber and maintain the low pollutant emission performance of the gas turbine.

[0051] It should be clear that in the embodiment of the present application, the flow path of the air from the outside of the first premixing nozzle 2 into the inside of the second premixing channel 7 is as follows: Figure 5 Specifically, part of the air entering the second premixing channel 7 is directed along the route A. Figure 5 The route C shown in FIG. 1 enters the first premixing channel 6 to form a mixed gas; while the other part follows the route C shown in FIG. Figure 5 The path D shown enters the second half of the second premixing flow channel 7 to form a mixed gas. It is easy to understand that in the embodiment of the present application, the ratio of air entering the first premixing flow channel 6 and the second premixing flow channel 7 can be controlled based on the cross-sectional area of ​​the air through hole 21. If the cross-sectional area of ​​the air through hole 21 is larger, more air will enter the first premixing flow channel 6, and less air will enter the second premixing flow channel 7; if the cross-sectional area of ​​the air through hole 21 is smaller, less air will enter the first premixing flow channel 6, and more air will enter the second premixing flow channel 7.

[0052] It is easy to understand that if you want to form a mixed gas in the second premixing channel 7, you need to introduce fuel into the second premixing channel 7. In the embodiment of the present application, the fuel can be introduced into the second premixing channel 7 through a structure similar to the fuel nozzle 3. In order to ensure that the fuel introduced into the second premixing channel 7 can be evenly mixed with the air in the second premixing channel 7 to form a mixed gas. Figure 4 As shown, the interior of the first premixing nozzle 2 is provided with fuel flow channels 22 corresponding to multiple support rods 8 one by one, and each fuel flow channel 22 extends to the corresponding support rod 8; each support rod 8 is provided with multiple second spray holes 81, and the second spray holes 81 are used to connect the fuel flow channel 22 and the second premixing flow channel 7.

[0053] Specifically, in this embodiment, fuel can be delivered to the second premixing channel 7 through the fuel channel 22 and the second nozzle hole 81. Compared with the use of a spray bar to deliver fuel, this structure can deliver fuel so that the fuel and the air along the circumference of the second premixing channel 7 can be evenly mixed.

[0054] It should be clear that in the embodiment of the present application, there is no limitation on the position and number of the second spray holes 81 on the support rod 8. However, in order to further make the air and fuel in the second premixing flow channel 7 be mixed evenly, as shown in FIG. Figure 3 and Figure 4 As shown, the inner diameter of each second spray hole 81 increases gradually along the second direction, the second direction is parallel to the radial direction of the first premixing nozzle 2, and points from the inside of the first premixing nozzle 2 to the outside (that is, the direction from the head end of the support rod 8 corresponding to each second spray hole 81 to the end).

[0055] It should be understood that, firstly, each second nozzle hole 81 distributed along the second direction can effectively prevent the ejected fuel beam from being too concentrated and unable to be evenly dispersed in the second premixing channel 7. Secondly, the flow rate of the fluid is equal to the flow velocity multiplied by the cross-sectional area. In the "return" type pipeline (that is, the second premixing channel 7), the closer to the outer wall of the pipeline (that is, the side wall of the second premixing nozzle 1), the larger the cross-sectional area of ​​the pipeline is, and the closer to the inner wall of the pipeline (that is, the side wall of the first premixing nozzle 2), the smaller the cross-sectional area of ​​the pipeline is. That is to say, in this embodiment, the closer to the side wall of the second premixing nozzle 1, the larger the air flow rate is, and the closer to the side wall of the first premixing nozzle 2, the smaller the air flow rate is, that is, the air flow rate in the second premixing channel 7 along the second direction increases. Since the inner diameter of each second nozzle hole 81 along the second direction also increases, that is, the fuel flow rate of the fuel ejected based on each second nozzle hole 81 along the second direction increases, the air and fuel at each location in the second premixing channel 7 can be mixed in equal amounts, that is, the fuel and air can be mixed more evenly.

[0056] In the embodiment of the present application, in order to further improve the mixing uniformity of fuel and air in the second premixing flow channel 7. Figure 4 As shown, a second swirler 9 is provided in the second premixing channel 7. The second swirler 9 has a similar function to the first swirler 5 described above, and will not be described in detail.

[0057] As can be seen from the background technology, the reason why the nozzle is damaged by flashback is due to high temperature ablation. In the embodiment of the present application, in order to cool down the first premixing nozzle 2 and avoid high temperature ablation of the first premixing nozzle 2, as shown in FIG. Figure 4 As shown, the first premixing nozzle 2 is provided with second air channels 11 corresponding to the plurality of support rods 8 one by one; each second air channel 11 extends to the inside of the corresponding support rod 8 and passes through the second premixing nozzle 1 .

[0058] Specifically, in the embodiment of the present application, the air outside the second premixing nozzle 1 can be Figure 5The air enters the second air flow channel 11 through the route B in the figure, and is ejected from the third nozzle 24 to the combustion chamber to participate in combustion. Since the air temperature outside the second premixing nozzle 1 is relatively low, it can cool down the first premixing nozzle 2 and prevent high-temperature ablation of the first premixing nozzle 2.

[0059] Specifically, Figure 4 and Figure 5 As shown, when the gas turbine is working, a small part of the air outside the second premixing nozzle 1 flows along Figure 5 After the first premixing nozzle 2 is cooled by the route B shown in the figure, the air enters the combustion chamber through the third nozzle 24 to participate in the combustion; a large part of the air flows along the Figure 5 The route A shown enters the second premixing channel 7 to participate in the subsequent formation of mixed gas. Figure 4 and Figure 5 As shown, part of the air entering the second premixing channel 7 flows along Figure 5 The route C shown in FIG. 1 enters the first premixing channel 6; the other part follows Figure 5 The flow continues along the route D shown in the second premixing flow passage 7. If the gas turbine is in a low power state, the gas turbine will continue to flow along the route D shown in the second premixing flow passage 7. Figure 5 The fuel is injected into the first premixing channel 6 through the fuel spray rod 3 along the route E in the figure. The fuel and air in the first premixing channel 6 can form a mixed gas, and the mixed gas can be injected into the first premixing channel 6 through the fuel spray rod 3. Figure 5 The route G shown in FIG. enters the combustion chamber to participate in combustion. If the gas turbine is in a high power state, it follows Figure 5 The route F in the figure injects fuel into the second premixing channel 7 through the fuel channel 22. The fuel and air in the second premixing channel 7 can be mixed to form a mixed gas, and the mixed gas can Figure 5 The route H shown in FIG. 1 enters the combustion chamber and participates in combustion.

[0060] It should be clear that, since the inner diameter of the first premixing flow channel proposed in the embodiment of the present application decreases along the first direction (i.e., the flow direction of the mixed gas), the flow velocity of the mixed gas increases after passing through the first premixing flow channel. In other words, the nozzle proposed in the embodiment of the present application can reduce the probability of flashback in the combustion chamber, or reduce the severity of flashback in the combustion chamber.

[0061] After introducing the nozzle proposed in the embodiment of the present application, the gas turbine proposed in the embodiment of the present application is introduced below. Specifically, the gas turbine includes the nozzle proposed in any one of the above embodiments.

[0062] Since the embodiment of the gas turbine of the present application has a nozzle similar to the above, the gas turbine in this embodiment also has similar technical effects as mentioned above, which will not be described in detail here.

[0063] Although the embodiments of the present application have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present application, and that the scope of the present application is defined by the appended claims and their equivalents.

Claims

1. A nozzle, applied to a gas turbine, the gas turbine comprising a combustion chamber, characterized in that: The nozzle comprises: A first premixing nozzle (2); A first air flow channel (4) and a first premixing flow channel (6) are sequentially arranged inside the first premixing nozzle (2); the first air flow channel (4) is used to guide air to the first premixing flow channel (6); the first premixing flow channel (6) is used to mix air and fuel to form a mixed gas, and is used to guide the mixed gas to the combustion chamber; the inner diameter of the first premixing flow channel (6) decreases along a first direction, the first direction is parallel to the axis of the first premixing nozzle (2), and points from the head end to the end of the first premixing nozzle (2); A fuel spray rod (3) is used to guide the fuel to the first premixing flow channel (6).

2. The nozzle according to claim 1, characterized in that The fuel nozzle rod (3) is located inside the first premixing nozzle (2), and the axis center lines of the fuel nozzle rod (3) and the first premixing nozzle (2) coincide with each other. The end of the fuel nozzle rod (3) extends to the inside of the first premixing channel (6), and the end wall (36) of the fuel nozzle rod (3) is provided with a plurality of first spray holes (37).

3. The nozzle according to claim 2, characterized in that The end wall (36) is in the shape of a hollow sphere, and each of the first spray holes (37) is evenly distributed on the end wall (36).

4. The nozzle according to claim 1, characterized in that The side wall of the first premixing nozzle (2) is provided with a plurality of air through holes (21), and each air through hole (21) is in the shape of an elongated strip.

5. The nozzle according to claim 4, characterized in that A first swirler (5) is arranged in the first air flow channel (4).

6. The nozzle according to any one of claims 1 to 5, characterized in that Also includes: A second premixing nozzle (1) is sleeved on the outside of the first premixing nozzle (2), and a second premixing flow channel (7) is provided between the second premixing nozzle (1) and the first premixing nozzle (2); A plurality of support rods (8), each support rod (8) being evenly distributed around the circumference of the first premixing nozzle (2), and one end of each support rod (8) being connected to the inner wall of the second premixing nozzle (1); and the other end of each support rod (8) being connected to the outer wall of the first premixing nozzle (2).

7. The nozzle according to claim 6, characterized in that The first premixing nozzle (2) is provided with fuel flow channels (22) corresponding to the plurality of support rods (8) one by one, and each fuel flow channel (22) extends into the corresponding support rod (8); each support rod (8) is provided with a plurality of second spray holes (81), and the second spray holes (81) are used to connect the fuel flow channel (22) and the second premixing flow channel (7).

8. The nozzle according to claim 7, characterized in that The inner diameter of each second spray hole (81) increases gradually along the second direction, the second direction is parallel to the radial direction of the first premixing nozzle (2), and points from the inside to the outside of the first premixing nozzle (2).

9. The nozzle according to claim 6, characterized in that The first premixing nozzle (2) is provided with second air flow channels (11) corresponding one to one with the plurality of support rods (8); each second air flow channel (11) extends to the inside of the corresponding support rod (8) and passes through the second premixing nozzle (1).

10. A gas turbine, characterized in that: Comprising a nozzle as claimed in any one of claims 1 to 9.

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