Bundling branch pipe structure

Abstract

The invention relates to the technical field of aero-engines, and discloses a bundling branch pipe structure which is characterized in that multiple branch pipe inlets are communicated with a fuel header pipe, and multiple branch pipe outlets are located at different heads of a combustion chamber respectively; the plurality of branch pipes are bundled in the same bundling header pipe; the bundling branch pipe structure distributes fuel to all the branch pipes through the fuel main pipe, and then all the branch pipes directly convey the fuel to different heads. Based on the local mass principle, fuel flow paths entering all the branch pipes are bundled together in a bundling mode, fuel of all the branch pipes is independently distributed at the branch positions, the high independence of work of all the branch pipes can be kept by actively controlling the flow capacity of the front ends of all the branch pipes and separating the work environment of all the branch pipes, and the reliability of fuel distribution is improved. And the branch pipe flow is strictly proportionally distributed according to the preset value, so that the high uniformity of fuel distribution of the fuel header pipe is ensured, and the fuel supply uniformity is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of aeroengines, and particularly relates to a cluster manifold structure. Background Art

[0002] In order to eliminate about 70% of carbon emissions from the fuel end in the aviation industry, various countries and major aeroengine manufacturers have mainly focused on zero-carbon fuels such as hydrogen fuel.

[0003] Currently, when designing the combustion chamber of a hydrogen fuel aeroengine or making adaptive improvements to the combustion chamber of a traditional aviation kerosene fuel engine for hydrogen fuel application, generally, the fuel storage tank is connected through a fuel main pipe, and the fuel main pipe is then connected to the combustion chamber of the aeroengine through branch pipes. As a non-compressible liquid fuel, traditional aviation kerosene fuel can ensure good uniformity of the distribution of the fuel main pipe by keeping the flow areas of the branch pipes consistent.

[0004] Due to the large differences in physical properties such as the physical state, density, and viscosity between hydrogen fuel and traditional aviation kerosene fuel, hydrogen fuel is used in the state of hydrogen gas, while traditional aviation kerosene fuel is used in the liquid state. Hydrogen fuel belongs to a small molecule gaseous fuel and has compressibility and easy diffusibility. The compressibility of gaseous hydrogen fuel makes the traditional design method of only keeping the flow areas of the branch pipes consistent no longer applicable. The density of hydrogen gas is no longer uniform everywhere inside the fuel main pipe. During the process of hydrogen gas flowing from the fuel main pipe into the branch pipes, it is very easy to be compressed and diffused, and hydrogen gas is sensitive to slight differences in the flow area, resulting in uneven flow distribution of the fuel main pipe to each branch pipe, significantly increasing the difficulty of uniformly supplying hydrogen fuel to each head of the combustion chamber. Furthermore, when each branch pipe supplies fuel to the combustion chamber, it deviates from the design, easily leading to a series of problems such as flashback, unstable combustion, decreased combustion efficiency, deterioration of the outlet temperature field quality, and high NO x emissions. Summary of the Invention

[0005] In view of this, the present invention provides a cluster manifold structure to solve the problems that the density of hydrogen gas is uneven everywhere inside the fuel main pipe, it is very easy to be compressed and diffused during the process of hydrogen gas flowing from the fuel main pipe into the branch pipes, hydrogen gas is sensitive to slight differences in the flow area, resulting in uneven flow distribution of the fuel main pipe to each branch pipe, significantly increasing the difficulty of uniformly supplying hydrogen fuel to each head of the combustion chamber, and further causing each branch pipe to deviate from the design when supplying fuel to the combustion chamber, easily leading to flashback, unstable combustion, decreased combustion efficiency, deterioration of the outlet temperature field quality, and high NO x emissions.

[0006] The present invention provides a cluster manifold structure, including:

[0007] Multiple independent branch pipes, with their inlets all connected to the fuel main pipe, and the outlets of the multiple branch pipes are respectively located at the heads of different positions in the combustion chamber of the aeroengine;

[0008] A bundled main pipe, with multiple independent branch pipes bundled in the same bundled main pipe;

[0009] The described bundled branch pipe structure is suitable for distributing fuel from the fuel main pipe to each branch pipe, and then directly delivering fuel to different heads in the combustion chamber of the aeroengine by each branch pipe. Beneficial effects: By adopting the above technical solution, based on the local mass principle, the fuel flow paths entering each branch pipe are bundled together in a bundled manner, and the fuel of each branch pipe is separately distributed at the divergence point. Moreover, by actively controlling the flow capacity at the front end of each branch pipe and separating the working environments of each branch pipe, the strong independence of each branch pipe's work can be maintained, enabling the flow rate of each branch pipe to be strictly proportionally distributed according to the preset value, thereby ensuring a high degree of uniformity in the fuel distribution by the fuel main pipe and improving the fuel supply uniformity; when each branch pipe supplies fuel to the combustion chamber, it meets the design requirements, prevents flashback, ensures stable combustion and improves combustion efficiency, improves the quality of the outlet temperature field, and reduces the emission of NO x emissions. This application has the characteristics of high uniformity and high controllability in the separate distribution of fuel for each branch pipe, provides a suitable solution for breaking through the technical bottleneck of the reliable supply design of aeroengine fuel, promotes the development of the aviation industry; and ensures the stable and efficient operation of the aeroengine.

[0010] Optionally, the voids in the bundled main pipe are filled with solid fillers. Beneficial effects: By adopting the above technical solution, it ensures that the fixation of each branch pipe is more stable and guarantees the flow rate stability.

[0011] Optionally, the branch pipe and the bundled main pipe are integrally manufactured. Beneficial effects: By adopting the above technical solution, the cost is reduced.

[0012] Optionally, a pressure stabilizing distribution cavity is provided at the end where the fuel main pipe is connected to the branch pipe. Beneficial effects: By adopting the above technical solution, it ensures the uniformity at the source of fuel distribution and further guarantees the degree of uniformity of fuel distribution.

[0013] Optionally, the fuel is a gaseous fuel or a liquid fuel. Beneficial effects: By adopting the above technical solution, the described bundled branch pipe structure of this application is compatible with various gaseous fuels and liquid fuels, and can maintain a high degree of fuel distribution uniformity by making fine adjustments according to the fuel characteristics.

[0014] Optionally, the gaseous fuel is hydrogen. Beneficial effects: By adopting the above technical solution in this application, when the fuel is hydrogen, the difficulty of uniformly supplying hydrogen fuel to each head of the combustion chamber is significantly reduced. As a result, when each manifold supplies fuel to the combustion chamber, it can ensure the design requirements, prevent flashback, ensure stable combustion, improve the combustion efficiency, improve the quality of the outlet temperature field, and reduce the emission of NO x ; It provides a suitable solution to break through the technical bottleneck of the reliable supply design of hydrogen fuel for aeroengines, promotes the engineering application of hydrogen fuel in the aviation industry, and ensures the stable and efficient operation of hydrogen fuel aeroengines.

[0015] Optionally, according to the number of heads of the aeroengine combustion chamber, a partial length cluster manifold structure with a corresponding length and corresponding head positions is intercepted. Beneficial effects: By adopting the above technical solution in this application, the cluster manifold structure can be flexibly adjusted according to the specific number of heads of the combustion chamber, and the adaptability of the cluster manifold structure is wider.

[0016] Optionally, the cluster main pipe is connected end to end to form a closed loop; the heads of the aeroengine combustion chamber are arranged staggeredly along the closed loop, and the outlets of multiple manifolds corresponding to the heads are arranged staggeredly along the closed loop. Beneficial effects: By adopting the above technical solution in this application, while having a good assembly anti-misalignment function, it further achieves the effect of breaking the circumferential symmetry, enhancing the combustion stability of the combustion chamber.

[0017] Optionally, the number of heads of the aeroengine combustion chamber is twelve, and the number of manifolds is twelve.

[0018] Optionally, the fuel main pipe is provided with a main pipe inlet, and fuel is introduced through the main pipe inlet. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required for use in the description of the specific embodiments or the prior art. Obviously, the following drawings are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0020] Figure 1 Structural schematic of the cluster manifold structure provided in the embodiment of the present invention Figure 1 ;

[0021] Figure 2 Structural schematic of the cluster manifold structure provided in the embodiment of the present invention Figure 2 ;

[0022] Figure 3 Fuel distribution schematic of the cluster manifold structure provided in the embodiment of the present inventionFigure 2 ;

[0023] Figure 4 This is a perspective structural schematic diagram of the cluster branch pipe structure provided in the embodiment of the present invention;

[0024] Figure 5 This is a schematic diagram of fuel flow at the branch pipe outlet closest to the main pipe inlet of the cluster branch pipe structure provided in the embodiment of the present invention;

[0025] Figure 6 This is a schematic diagram of fuel flow at the branch pipe outlet farthest from the main pipe inlet of the cluster branch pipe structure provided in the embodiment of the present invention.

[0026] Explanation of reference numerals:

[0027] 1. Branch pipe; 2. Fuel main pipe; 3. Cluster main pipe; 4. Pressure stabilizing and distributing cavity; 5. Main pipe inlet. Specific embodiments

[0028] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative efforts fall within the scope of protection of the present invention.

[0029] Currently, there is a lack of mature reference experience for the design of fuel main pipes for hydrogen fuel aeroengines. The traditional solutions for fuel main pipes of aviation kerosene are mainly followed, and the problem of uneven hydrogen fuel distribution is overcome by increasing or decreasing the size of the fuel main pipe or branch pipes; the effects achieved by the above methods of increasing or decreasing the size of the fuel main pipe or branch pipes are very limited; there are limits to the increase and decrease of the size of the fuel main pipe or branch pipes, which easily lead to problems such as excessive volume, excessive weight, or too fast air flow velocity. By the method of increasing or decreasing the size, even for a certain combustion chamber, the uniformity of the fuel main pipe and branch pipes is relatively good. However, when changing the combustion chamber or for hydrogen fuel combustion chambers in more application scenarios, the uniformity of the fuel main pipe and branch pipes will be difficult to guarantee. In addition, the controllability of the method of adjusting the size of the branch pipes is poor; this is because when adjusting the throttling part of a certain branch pipe, the flow rates of the various branch pipes restrict and affect each other; adjusting a single branch pipe induces a flow imbalance in other branch pipes, which easily leads to a dilemma where the fuel main pipe cannot take all aspects into account when adjusting the hydrogen fuel flow rate, and the overall controllability is poor. For the above reasons, the present application proposes a cluster branch pipe structure.

[0030] Such as Figures 1 to 6 A specific embodiment of the cluster branch pipe structure shown includes: a plurality of independent branch pipes 1 and a cluster main pipe 3.

[0031] As Figure 4 shown, the inlets of multiple independent branch pipes 1 are all connected to the fuel main pipe 2, and the outlets of the multiple branch pipes 1 are respectively located at the heads of different positions in the combustion chamber of the aero-engine. The multiple independent branch pipes 1 are bundled in the same bundling main pipe 3. The bundling branch pipe structure is adapted to distribute fuel from the fuel main pipe 2 to each branch pipe 1, and then each branch pipe 1 directly conveys fuel to different heads in the combustion chamber of the aero-engine. Specifically, the fuel is gaseous fuel or liquid fuel. More specifically, the gaseous fuel is hydrogen, also known as hydrogen fuel.

[0032] Furthermore, as Figure 1 shown, the void in the bundling main pipe 3 is filled with solid filler, Figure 1 and the solid filler in

[0033] is not shown. Figure 2 Furthermore, as

[0034] shown, the branch pipe 1 and the bundling main pipe 3 are integrally manufactured. Figure 4 Furthermore, as

[0035] shown, a pressure stabilizing distribution cavity 4 is provided at the end where the fuel main pipe 2 is connected to the branch pipe 1. The fuel main pipe 2 is provided with a main pipe inlet 5, and fuel is introduced through the main pipe inlet 5.

[0036] Furthermore, according to the number of heads in the combustion chamber of the aero-engine, a partial length bundling branch pipe structure with corresponding length and corresponding head positions is intercepted.

[0037] Specifically, as Figure 4 shown, the bundling main pipe 3 is connected end to end to form a closed loop; the heads of the combustion chamber of the aero-engine are arranged staggeredly along the closed loop, and the outlets of the multiple branch pipes 1 corresponding to the heads are arranged staggeredly along the closed loop. More specifically, the number of heads in the combustion chamber of the aero-engine is twelve, and the number of branch pipes 1 is twelve.

[0038] Based on the invention principle of local quality, this application divides the whole into multiple parts, enabling each part to be fully in an ideal state, so that the whole is also in an ideal state, and proposes a clustered branch pipe structure. Since the intake air volume at the head of each combustion chamber of a hydrogen fuel aviation engine is certain, and the hydrogen fuel entering the head of a single combustion chamber only burns out in this head and does not enter other heads; therefore, it can be considered that only the hydrogen fuel entering the head of a certain combustion chamber completes the process from flowing into the fuel manifold 2 to entering this combustion chamber head through the branch pipe 1 until it burns out. After the above hydrogen fuel flows into the fuel manifold 2, it will directly go to the combustion chamber head it is going to, without any flow loss along the way. Tracing back its flow path is a single beam flow path from the hydrogen fuel manifold inlet 5 to the combustion chamber head. Thus, extending to each combustion chamber head, the conclusion can be drawn that actually, the hydrogen fuel flowing through the fuel manifold 2 into the combustion chamber has been distributed in several mutually isolated flow pipes corresponding to the number of heads, and the clustered manifold 3 is equivalent to the clustering of each beam of flow pipes. However, in previous designs, the principle of local quality was not used to materialize each beam of hydrogen fuel flow pipes, so there is no obvious demarcation between each beam of hydrogen fuel, which affects the flow process mutually, and finally causes some hydrogen fuel to be unable to flow into the combustion chamber stably and smoothly according to the established track, significantly increasing the unevenness of hydrogen fuel distribution.

[0039] Since the inlet flow rate and outlet flow rate of each branch pipe 1 being clustered are the same, therefore, each hydrogen fuel flow pipe can be regarded as from the main inlet 5 of the fuel manifold until the branch pipe 1 before entering the combustion chamber head. Due to the easy diffusibility of hydrogen fuel, in order to avoid the instability of the flow area between each branch pipe 1, the space between the branch pipes 1 is filled with solid fillers.

[0040] The hydrogen fuel in each branch pipe 1 enters the combustion chamber head, as Figure 3 and Figure 4 shown, Figure 3 the dotted arrows in

[0041] schematically indicate the flow direction of the fuel. In order to avoid interference between the branch pipes 1 entering the head of the engine combustion chamber and affecting the stable supply of hydrogen fuel, the outlets of the branch pipes 1 extending out are arranged in sequence along the circumferential position, and there is no throttling, air flow intersection or dispersion in the flow path, ensuring the independence of the work of each hydrogen fuel branch pipe 1, which is conducive to regulating the hydrogen fuel flow distribution of each branch pipe 1 by controlling the flow area and internal structure of the branch pipes 1 at different positions. Figure 4 shown. Its working principle is briefly described as follows: All the hydrogen fuel of the hydrogen fuel full-ring combustion chamber enters the pressure-stabilizing distribution chamber 4 from the main inlet 5 of the fuel manifold 2. In the pressure-stabilizing distribution chamber 4, the hydrogen fuel flows evenly, and is divided into N hydrogen fuel airflows at the independent branch total manifold of the branch pipes 1, and respectively enters the independent branches of the N branch pipes 1, flows through to the outlet of the branch pipe 1, and is supplied into the combustion chamber.Figure 5 Further provide the limiting state flow path for the hydrogen fuel to reach the outlet of the branch pipe 1 closest to the inlet of the main pipe 5; Figure 6 Further provide the limiting state flow path for the hydrogen fuel to reach the outlet of the branch pipe 1 farthest from the inlet of the main pipe 5. Figure 5 And Figure 6 The dashed arrows in indicate the flow direction of the fuel.

[0042] This application can provide a fuel supply scheme for a combustion chamber with circumferential hierarchical partition combustion organization characteristics. For example, a hierarchical fuel supply strategy of less rich oil - more lean oil is adopted in the circumferential direction. While ensuring the ignition performance, it reduces the emission of NO x etc. While breaking the circumferential symmetry of the combustion chamber, it can also eliminate the circumferential oscillation mode, improve the combustion stability of the combustion chamber, and have a good function of preventing assembly errors. The above effect analysis is briefly described as follows.

[0043] Since the present invention greatly enhances the independent controllability of the hydrogen fuel in each hydrogen fuel branch pipe 1, the bundled branch pipe structure of this application is different from the traditional hydrogen fuel main pipe; the flow distribution of the traditional hydrogen fuel main pipe is uneven, which is passively generated by the design result, the flow rate of the hydrogen fuel is uncontrollable, and it is harmful to the combustion chamber. This application accurately distributes the hydrogen fuel to each hydrogen fuel branch pipe 1, and then accurately distributes the hydrogen fuel flow rate corresponding to each head of the combustion chamber; if a small number of combustion chamber heads with a relatively high equivalence ratio are matched with the remaining majority of combustion chamber heads with a relatively low equivalence ratio, while ensuring the ignition performance and circumferential flame connection reliability of the combustion chamber through the combustion chamber heads with a relatively high equivalence ratio, the overall equivalence ratio is still at a relatively low level, thereby reducing the emission of NO x emissions. The small number of combustion chamber heads with a relatively high equivalence ratio means less rich oil, and the majority of combustion chamber heads with a relatively low equivalence ratio means more lean oil. The above design of this application is also beneficial to breaking the circumferential symmetry of the combustion chamber, blocking the continuous propagation path of the circumferential combustion wave of the combustion chamber, thereby eliminating the circumferential oscillation combustion mode and improving the combustion stability of the combustion chamber. In addition, since the positions of the outlets of each hydrogen fuel branch pipe 1 are staggered with each other in the circumferential direction, when the hydrogen fuel branch pipe 1 is connected to the combustion chamber, the one-to-one correspondence between each branch pipe 1 and each head of the combustion chamber can also be clarified. While having a good function of preventing assembly errors, it further achieves the effect of breaking the circumferential symmetry and enhancing the combustion stability of the combustion chamber.

[0044] Through numerical simulation and comparative calculation, the bundled branch pipe structure of this application can reduce the unevenness level of the existing fuel distribution from 5% to less than 1%.

[0045] Although the embodiments of the present invention have been described with reference to the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations all fall within the scope defined by the appended claims.

Claims

1. A cluster branch pipe structure, characterized in that, Comprising: Multiple independent branch pipes (1) with their inlets all communicating with a fuel main pipe (2), and the outlets of the multiple branch pipes (1) are respectively located at the heads of different positions in an aeroengine combustion chamber; A bundled main pipe (3), with the multiple independent branch pipes (1) bundled in the same bundled main pipe (3); The bundled branch pipe structure is adapted to distribute fuel from the fuel main pipe (2) to each branch pipe (1), and then each branch pipe (1) directly supplies fuel to different heads in the aeroengine combustion chamber.

2. The cluster header structure according to claim 1, wherein, The void in the bundled main pipe (3) is filled with a solid filler.

3. The cluster header structure according to claim 2, wherein, The branch pipe (1) and the bundled main pipe (3) are integrally manufactured.

4. The cluster branch pipe structure according to any one of claims 1-3, characterized in that A pressure stabilizing distribution chamber (4) is provided at the end where the fuel main pipe (2) communicates with the branch pipe (1).

5. The cluster branch pipe structure according to any one of claims 1-3, characterized in that, The fuel is a gaseous fuel or a liquid fuel.

6. The cluster branch pipe structure according to claim 5, characterized in that, The gaseous fuel is hydrogen.

7. The cluster branch pipe structure according to any one of claims 1-3, characterized in that, According to the number of heads of the aeroengine combustion chamber, a partial length of the bundled branch pipe structure with a corresponding length and corresponding head positions is intercepted.

8. The cluster branch pipe structure according to any one of claims 1-3, characterized in that, The bundled main pipe (3) is connected end to end to form a closed loop; the heads of the aeroengine combustion chamber are arranged staggeredly along the closed loop, and the outlets of the multiple branch pipes (1) corresponding to the heads are arranged staggeredly along the closed loop.

9. The cluster header structure according to claim 8, wherein, The number of heads of the aeroengine combustion chamber is twelve, and the number of branch pipes (1) is twelve.

10. The cluster header structure according to any one of claims 1-3, characterized in that, The fuel main pipe is provided with a main pipe inlet (5), and fuel is introduced through the main pipe inlet (5).

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