A fuel supply device for widening the boundary of a combustion chamber

Abstract

The present application provides a fuel supply device for widening the combustion chamber boundary, belonging to the field of aviation engine technology, specifically including a fuel main pipe, a plurality of first nozzles and a plurality of second nozzles, the number of first nozzles being greater than the number of second nozzles, the first nozzle and the second nozzle both including a main-stage fuel injection assembly and a secondary-stage fuel injection assembly, the flow rate of the secondary-stage fuel injection assembly of the second nozzle being greater than the flow rate of the secondary-stage fuel injection assembly of the first nozzle, when the engine is ignited or operating at low speed, the main-stage fuel injection assembly of the first nozzle and the second nozzle stops supplying fuel, and the secondary-stage fuel injection assembly of the first nozzle and the second nozzle supplies fuel, and when the engine is operating at high speed, the main-stage fuel injection assembly and the secondary-stage fuel injection assembly of the first nozzle and the second nozzle supply fuel at the same time. Through the processing scheme of the present application, the ignition-extinguishing boundary is widened under low operating conditions, and the flow rate ratio of the main and secondary nozzles is balanced under high operating conditions, ensuring higher combustion efficiency and outlet temperature field.

Description

Technical Field

[0001] The present application relates to the field of aircraft engines, and in particular to a fuel supply device for widening the boundary of a combustion chamber. Background Art

[0002] Fuel nozzles are critical components in aircraft engine combustion chambers. Their primary function is to atomize fuel and inject it into the combustion chamber for mixing with air for combustion. As aircraft engine flight envelopes expand, the fuel flow rate range is also increasing. Therefore, modern aircraft engine combustion chamber fuel nozzles are generally designed with dual oil paths to accommodate this wide range. However, with increasing engine requirements for combustor temperature increases and higher pollutant emissions, current fuel supply methods often struggle to balance combustion chamber performance across various operating conditions. To address this issue, a zoned fuel supply method has been proposed. The patent filed by the applicant proposes a fuel-rich direct-mix zoned combustor that balances high fuel-to-air ratio combustion chamber ignition and low-operating-condition stability with high-efficiency, low-smoke combustion performance under high-operating conditions. This zoned fuel supply method utilizes a centrifugal nozzle in the secondary stage to ensure excellent ignition capability and low-operating-condition stability. The main stage utilizes multi-point injection direct-mix combustion technology to better adapt to drastic changes in engine combustion chamber operating conditions, resulting in improved responsiveness and tracking. However, for some engines, further expanding the low-operating-state margin requires further reducing the secondary nozzle flow rate. This results in lower secondary nozzle flow rates under high-power operating conditions, impacting combustion efficiency. Existing technologies, both domestically and internationally, employ a three-way design to balance combustion efficiency across all operating conditions, but this complicates the fuel system. Summary of the Invention

[0003] In view of this, the present application provides a fuel supply device that widens the combustion chamber boundary, solves the problems in the prior art, and widens the ignition-extinguishing boundary under low operating conditions.

[0004] The present application provides a fuel supply device for widening the combustion chamber boundary, which adopts the following technical solutions:

[0005] A fuel supply device for widening the boundary of a combustion chamber comprises a fuel main pipe, a plurality of first nozzles and a plurality of second nozzles, the fuel main pipe is annular, the plurality of first nozzles and second nozzles are evenly distributed along the circumference of the fuel main pipe, the number of first nozzles is greater than the number of second nozzles, the first nozzle and the second nozzle both comprise a main-stage fuel injection assembly and a secondary-stage fuel injection assembly, the flow rate of the secondary-stage fuel injection assembly of the second nozzle is greater than the flow rate of the secondary-stage fuel injection assembly of the first nozzle, when the engine is ignited or operating at a low speed, the main-stage fuel injection assemblies of the first and second nozzles stop supplying fuel, and the secondary-stage fuel injection assemblies of the first and second nozzles supply fuel, and when the engine is operating at a high speed, the main-stage fuel injection assemblies and the secondary-stage fuel injection assemblies of the first and second nozzles supply fuel at the same time.

[0006] Optionally, the first nozzle includes a first oil inlet circuit, a first valve, a first secondary oil circuit, a first main oil circuit, a first main nozzle, an oil supply circuit, a main additional nozzle, and a first secondary nozzle, wherein the first secondary nozzle is connected to the first oil inlet circuit via the first secondary oil circuit, the main additional nozzle is connected to the first main nozzle via the oil supply circuit, the first main nozzle is connected to the first valve via the first main oil circuit, and the first valve is connected to the first oil inlet circuit;

[0007] The first main-stage nozzle and the main-stage additional nozzle serve as the oil outlet mechanism of the main-stage injection assembly of the first nozzle, the first secondary-stage nozzle serves as the secondary-stage injection assembly of the first nozzle, the first valve is closed when the engine is ignited or at a low speed, and the first valve is opened when the engine is at a high speed.

[0008] Optionally, the second nozzle includes a second oil inlet circuit, a second valve, a second secondary oil circuit, a second main oil circuit, a second secondary nozzle and a second main nozzle, the second secondary nozzle is connected to the second oil inlet circuit through the second secondary oil circuit, the second main nozzle is connected to the second valve through the second main oil circuit, the second valve is connected to the second oil inlet circuit, the second valve is closed when the engine is ignited or at a low speed, and the second valve is opened when the engine is at a high speed.

[0009] Optionally, the fuel injection flow rate of the secondary fuel injection assembly of the second nozzle is 1.4-2 times the fuel injection flow rate of the secondary fuel injection assembly of the first nozzle.

[0010] Optionally, the fuel injection flow rate of the secondary fuel injection assembly of the first nozzle is 3-8 (g / s / MPa).

[0011] Optionally, the sum of the flow rates of the first secondary-stage nozzle and the primary-stage additional nozzle is equal to the injection flow rate of the secondary-stage injection assembly of the second nozzle.

[0012] Optionally, the number of the second nozzles is 2-4.

[0013] Optionally, a plurality of the second nozzles are adjacently arranged on the fuel main pipe.

[0014] Optionally, a plurality of the second nozzles are located at circumferential positions on the fuel manifold corresponding to the ignition nozzles.

[0015] In summary, this application has the following beneficial technical effects:

[0016] When the engine is ignited or operating at a low speed, the main-stage fuel injection assemblies of the first nozzle and the second nozzle stop supplying fuel, and the secondary-stage fuel injection assemblies of the first nozzle and the second nozzle supply fuel. The flow rate of the secondary-stage fuel injection assembly of the second nozzle is greater than the flow rate of the secondary-stage fuel injection assembly of the first nozzle. When the fuel flow rate in the combustion chamber is small, the second nozzle is locally rich in fuel, thereby improving the ignition and extinction boundary of the combustion chamber.

[0017] During high-pressure operation, the first and second valves are open, and the combined flow rates of the first secondary nozzle and the main-stage additional nozzle equal the injection flow rate of the secondary injection assembly of the second nozzle. The main-stage additional nozzle compensates for the low fuel flow rate of the first secondary nozzle. The supplementary first-stage fuel flow balances the flow rate ratio of the main and secondary nozzles, improving combustion efficiency.

[0018] When the first valve and the second valve are opened, the flow rate of the first main stage nozzle is equal to the flow rate of the second main stage nozzle, and the flow rate of the second sub-stage nozzle is equal to the flow rate of the main stage additional nozzle and the first sub-stage nozzle. The fuel injection amount of different nozzles is the same, ensuring a good outlet temperature field. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0020] Figure 1 It is a structural diagram of the combustion chamber;

[0021] Figure 2 Schematic diagram of the oil supply system;

[0022] Figure 3 Schematic diagram of the oil supply scheme for the first nozzle;

[0023] Figure 4 Schematic diagram of the oil supply scheme for the second nozzle.

[0024] Explanation of the accompanying symbols: 1. Fuel supply system; 2. Ignition nozzle; 3. Flame tube; 4. Swirl; 5. Casing; 6. Second nozzle; 7. First nozzle; 8. First oil inlet circuit; 9. First valve; 10. First secondary oil circuit; 11. First main oil circuit; 12. First main nozzle; 13. Oil supply circuit; 14. First secondary nozzle; 15. Main additional nozzle; 16. Second secondary nozzle; 68. Second oil inlet circuit; 69. Second valve; 610. Second secondary oil circuit; 611. Second main oil circuit; 612. Second main nozzle; 17. Fuel nozzle; 18. Fuel main pipe. DETAILED DESCRIPTION

[0025] The embodiments of the present application are described in detail below with reference to the accompanying drawings.

[0026] The following describes the embodiments of the present application through specific examples, and those skilled in the art can easily understand other advantages and effects of the present application from the contents disclosed in this specification. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. The present application can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present application. It should be noted that, in the absence of conflict, the features in the following embodiments and embodiments can be combined with each other. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without making creative work are within the scope of protection of this application.

[0027] It should be noted that various aspects of the embodiments within the scope of the appended claims are described below. It should be apparent that the aspects described herein can be embodied in a wide variety of forms, and any specific structure and / or function described herein is merely illustrative. Based on this application, it should be understood by those skilled in the art that an aspect described herein can be implemented independently of any other aspect, and two or more of these aspects can be combined in various ways. For example, any number of aspects described herein can be used to implement an apparatus and / or practice a method. In addition, other structures and / or functionalities other than one or more of the aspects described herein can be used to implement this apparatus and / or practice this method.

[0028] It should also be noted that the illustrations provided in the following embodiments are only schematic illustrations of the basic concept of the present application. The illustrations only show components related to the present application and are not drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component can be changed at will, and the component layout type may also be more complicated.

[0029] Additionally, in the following description, specific details are provided to provide a thorough understanding of the examples. However, one skilled in the art will appreciate that the aspects described can be practiced without these specific details.

[0030] like Figure 1 As shown, the combustion chamber includes a fuel supply system 1, an ignition nozzle 2, a flame tube 3, a swirler 4, and a casing 5. The fuel supply system 1 includes multiple fuel nozzles 17. The fuel is atomized by the fuel nozzles 17 and then sprayed into the flame tube 3. There, it mixes with the air flowing out of the swirler 4 and is ignited and burned by the ignition nozzle 2.

[0031] An embodiment of the present application provides a fuel supply device that widens the boundary of a combustion chamber.

[0032] like Figure 2-4 As shown, a fuel supply device for widening the boundary of a combustion chamber includes a fuel manifold 18, a plurality of first nozzles 7, and a plurality of second nozzles 6. The fuel manifold 18 is annular and has an odd number of fuel manifolds 18. The plurality of first nozzles 7 and second nozzles 6 are evenly distributed along the circumference of the fuel manifold 18. The number of first nozzles 7 is greater than the number of second nozzles 6. The first nozzles 7 and second nozzles 6 each include a primary injection assembly and a secondary injection assembly. The flow rate of the secondary injection assembly of the second nozzle 6 is greater than the flow rate of the secondary injection assembly of the first nozzle 7. During engine ignition or low-speed operation, which is when the engine speed is less than or equal to 70% of the maximum speed, the primary injection assemblies of the first nozzle 7 and the second nozzle 6 stop supplying fuel, while the secondary injection assemblies of the first nozzle 7 and the second nozzle 6 supply fuel. When the fuel flow rate in the combustion chamber is small, the second nozzle 6 is locally rich in fuel, thereby improving the ignition and flameout boundaries of the combustion chamber. During high-speed operation, which is when the engine speed reaches more than 70% of the maximum speed, the primary injection assemblies and secondary injection assemblies of the first nozzle 7 and the second nozzle 6 supply fuel simultaneously.

[0033] The first nozzle 7 includes a first oil inlet circuit 8, a first valve 9, a first secondary oil circuit 10, a first main oil circuit 11, a first main nozzle 12, an oil supply circuit 13, a main additional nozzle 15 and a first secondary nozzle 14. The first secondary nozzle 14 is connected to the first oil inlet circuit 8 through the first secondary oil circuit 10, the main additional nozzle 15 is connected to the first main nozzle 12 through the oil supply circuit 13, the first main nozzle 12 is connected to the first valve 9 through the first main oil circuit 11, the first valve 9 is connected to the first oil inlet circuit 8, and the first oil inlet circuit 8 is connected to the fuel manifold 18. Among them, the first main-stage nozzle 12 and the main-stage additional nozzle 15 serve as the oil outlet mechanism of the main-stage injection assembly of the first nozzle 7, and the first secondary-stage nozzle 14 serves as the oil outlet mechanism of the secondary-stage injection assembly of the first nozzle 7. The main-stage additional nozzle 15 and the first secondary-stage nozzle 14 of the first nozzle 7 form a dual-path centrifugal nozzle, the first secondary-stage nozzle 14 is a small-flow nozzle, and the main-stage additional nozzle 15 is connected to the first main-stage nozzle 12; the first valve 9 is closed when the engine is ignited or at a low speed, and the first valve 9 is opened when the engine is at a high speed.

[0034] The second nozzle 6 includes a second oil inlet circuit 68, a second valve 69, a second secondary oil circuit 610, a second main oil circuit 611, a second secondary nozzle 16 and a second main nozzle 612. The second secondary nozzle 16 is connected to the second oil inlet circuit 68 through the second secondary oil circuit 610. The second secondary nozzle 16 serves as the injection mechanism of the secondary injection assembly of the second nozzle 6. The second main oil circuit 611 serves as the injection mechanism of the main injection assembly of the second nozzle 6. The secondary injection assembly of the second nozzle 6 is a single-channel centrifugal nozzle. The second main nozzle 612 is connected to the second valve 69 through the second main oil circuit 611. The second valve 69 is connected to the second oil inlet circuit 68. The second oil inlet circuit 68 is connected to the fuel main pipe 18. The second valve 69 is closed when the engine is ignited or at a low speed. The second valve 69 is opened when the engine is at a high speed.

[0035] During high-pressure operation, the first valve 9 and the second valve 69 are open. The sum of the flow rates of the first secondary nozzle 14 and the main-stage additional nozzle 15 equals the injection flow rate of the secondary injection assembly of the second nozzle 6. The main-stage additional nozzle 15 compensates for the low fuel flow rate of the first nozzle 7, supplementing the first secondary fuel flow rate and increasing the fuel flow rate. The flow rate of the first main-stage nozzle 12 equals the flow rate of the second main-stage nozzle 612.

[0036] The fuel injection flow rate of the secondary injection assembly of the second nozzle 6 is 1.4-2 times the fuel injection flow rate of the secondary injection assembly of the first nozzle 7. In the embodiment of the present application, the flow rate of the second secondary nozzle 16 is 1.4-2 times the flow rate of the first secondary nozzle 14.

[0037] The fuel injection flow rate of the secondary fuel injection assembly of the first nozzle 7 is 3-8 (g / s / MPa). In the embodiment of the present application, the flow rate of the first secondary nozzle 14 is 3-8 (g / s / MPa).

[0038] The number of the second nozzles 6 is 2-4. A plurality of the second nozzles 6 are adjacently arranged on the fuel main pipe 18.

[0039] In one embodiment, during engine ignition, the first valve 9 and the second valve 69 are closed. Fuel is supplied by the first sub-stage nozzle 14 of the first nozzle 7 and the second sub-stage nozzle 16 of the second nozzle 6. At this time, the combustion chamber fuel flow is low, while the second nozzle 6 has a higher flow rate, receiving more fuel than the first nozzle 7. The second nozzle 6, located near the ignition nozzle 2, is able to successfully ignite first, thus improving the combustion chamber ignition margin. During engine lean burnout, the combustion chamber fuel flow is also low. At this time, the first valve 9 and the second valve 69 are closed, and the first sub-stage nozzle 14 of the first nozzle 7 and the second sub-stage nozzle 16 of the second nozzle 6 are supplied with fuel. The second nozzle 6 has a higher flow rate, receiving more fuel than the first nozzle 7, thus stabilizing the flame and improving the combustion chamber burnout margin. During high-pressure operation, the first valve 9 and the second valve 69 are opened, and all fuel lines begin supplying fuel. The sum of the flow rates of the first sub-stage nozzle 14 and the main-stage additional nozzle 15 of the first nozzle 7 equals the fuel flow of the second sub-stage nozzle 16 of the second nozzle 6. The primary additional nozzle 15 of the first nozzle 7 compensates for the low fuel flow rate of the first secondary nozzle 14, supplementing the fuel flow rate of the secondary injection shaft assembly of the first nozzle 7 and improving combustion efficiency. When the first valve 9 and the second valve 69 are open, the flow rate of the first primary nozzle 12 equals the flow rate of the second primary nozzle 612, and the flow rate of the second secondary nozzle 16 equals the flow rates of the primary additional nozzle 15 and the first secondary nozzle 14. The fuel injection amounts of the different nozzles are the same, ensuring a good outlet temperature field. Through these measures, this solution improves the ignition and flameout boundaries of the combustion chamber, while ensuring combustion efficiency and temperature distribution under a wide range of operating conditions and widening the operating boundaries of the combustion chamber.

[0040] The above description is merely a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in the present application should be included in the scope of protection of the present application. Therefore, the scope of protection of the present application should be based on the scope of protection of the claims.

Claims

1. A fuel supply device for widening the combustion chamber boundary, characterized in that: The fuel manifold comprises a fuel manifold, a plurality of first nozzles, and a plurality of second nozzles. The fuel manifold is annular, and the plurality of first nozzles and second nozzles are evenly distributed along the circumference of the fuel manifold. The number of first nozzles is greater than the number of second nozzles. The first nozzles and the second nozzles each comprise a primary fuel injection assembly and a secondary fuel injection assembly. The flow rate of the secondary fuel injection assembly of the second nozzle is greater than the flow rate of the secondary fuel injection assembly of the first nozzle. When the engine is ignited or operating at a low speed, the primary fuel injection assemblies of the first and second nozzles stop supplying fuel, and the secondary fuel injection assemblies of the first and second nozzles supply fuel. When the engine is operating at a high speed, the primary fuel injection assemblies and the secondary fuel injection assemblies of the first and second nozzles supply fuel simultaneously. The first nozzle includes a first oil inlet oil circuit, a first valve, a first auxiliary oil circuit, a first main oil circuit, a first main nozzle, an oil supply circuit, a main additional nozzle, and a first auxiliary nozzle. The first auxiliary nozzle is connected to the first oil inlet oil circuit via the first auxiliary oil circuit, and the main additional nozzle is connected to the first main nozzle via the oil supply circuit. The main additional nozzle and the first auxiliary nozzle of the first nozzle form a dual-path centrifugal nozzle. The first main nozzle is connected to the first valve via the first main oil circuit, and the first valve is connected to the first oil inlet oil circuit. The first primary nozzle and the primary additional nozzle serve as the oil outlet mechanism of the primary injection assembly of the first nozzle, the first secondary nozzle serves as the secondary injection assembly of the first nozzle, the first valve is closed when the engine is ignited or at a low speed, and is opened when the engine is at a high speed; The sum of the flow rates of the first secondary-stage nozzle and the main-stage additional nozzle is equal to the injection flow rate of the secondary-stage injection assembly of the second nozzle.

2. The fuel supply device for widening the combustion chamber boundary according to claim 1, characterized in that: The second nozzle includes a second oil inlet circuit, a second valve, a second auxiliary oil circuit, a second main oil circuit, a second auxiliary nozzle and a second main nozzle. The second auxiliary nozzle is connected to the second oil inlet circuit via the second auxiliary oil circuit. The second main nozzle is connected to the second valve via the second main oil circuit. The second valve is connected to the second oil inlet circuit. The second valve is closed when the engine is ignited or at a low speed, and is opened when the engine is at a high speed.

3. The fuel supply device for widening the combustion chamber boundary according to claim 1, characterized in that: The fuel injection flow rate of the secondary fuel injection assembly of the second nozzle is 1.4-2 times the fuel injection flow rate of the secondary fuel injection assembly of the first nozzle.

4. The fuel supply device for widening the combustion chamber boundary according to claim 1, characterized in that: The fuel injection flow rate of the secondary injection assembly of the first nozzle is 3-8 (g / s / ).

5. The fuel supply device for widening the combustion chamber boundary according to claim 1, characterized in that: The number of the second nozzles is 2-4.

6. The fuel supply device for widening the combustion chamber boundary according to claim 1, characterized in that: A plurality of the second nozzles are adjacently arranged on the fuel main pipe.

7. The fuel supply device for widening the combustion chamber boundary according to claim 1, characterized in that: A plurality of the second nozzles are located on the circumferential side of the fuel manifold and correspond to the ignition nozzles.

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