High-disturbance spray rod structure based on plasma excitation coupling pneumatic auxiliary atomization

Abstract

The invention discloses a high-disturbance spray rod structure based on plasma excitation coupling pneumatic auxiliary atomization, and relates to the technical field of aero-engine afterburners. Comprising a shell which is provided with an air inlet; the fuel oil pipeline is provided with an oil conveying channel; the fuel oil pipeline extends into the shell, and an air channel is formed between the fuel oil pipeline and the shell; the first insulating table is provided with a collision atomization area and an atomization development area; the first insulating table is connected to the output end of the fuel pipeline, and a plurality of oil-gas atomizing channels are arranged at the neck; a second insulating stage having a plasma discharge region; the second insulating table is clamped with the first insulating table; the high-voltage electrode is positioned between the first insulating table and the second insulating table; and the grounding electrode is positioned between the second insulating table and the shell. According to the high-disturbance spray rod, plasma excitation, pneumatic auxiliary atomization and cross collision are mutually coupled, three-time continuous action is carried out on fuel oil spray, and the fuel oil atomization performance of the high-disturbance spray rod is improved.

Description

Technical Field

[0001] The invention relates to the technical field of afterburner combustion chambers of aviation engines, and in particular to a high-disturbance spray bar structure based on plasma excitation coupled pneumatic assisted atomization. Background Art

[0002] When the afterburner technology is used in the afterburner, the distribution of fuel in the combustion chamber becomes a key factor affecting the combustion performance. The atomization quality of the fuel is directly related to the stable combustion characteristics and ignition performance of the afterburner. Therefore, the nozzle, as the core component of the afterburner, is of great importance. Compared with the nozzle design in the main combustion chamber, the nozzle structure in the afterburner is simpler. The direct-injection nozzle has been widely used due to its simple structure and easy processing.

[0003] However, with the continuous improvement of aircraft engine performance requirements, the inlet temperature of the afterburner continues to rise, while the oxygen content gradually decreases, which undoubtedly brings new challenges to the design of the afterburner. Although the direct-injection nozzle has the advantages of simple structure and convenient processing, its jet angle is small and the fuel distribution range is limited, making it difficult to achieve uniform atomization of the fuel within a short distance. This leads to large differences in combustion performance between the nozzles arranged in an annular manner in the afterburner, poor cross-flame effect, and easy carbon deposition and ablation in the combustion chamber, which cannot meet the high performance requirements of the new generation of integrated afterburner.

[0004] In view of the complex structure and harsh working conditions of aircraft engine combustion chambers, the research on plasma technology in the field of combustion has gradually attracted widespread attention from scholars at home and abroad in recent years. The development of this technology provides new ideas and directions for further improvement and optimization of aircraft engine nozzles.

[0005] The Chinese invention patent application with application number CN202211507704.9, titled A fuel spray rod and a fuel injection device, can achieve multiple embedded self-excited swept fuel nozzle flow channels under the size limit of the original straight hole fuel spray rod, while ensuring that its flow resistance is equivalent to that of the original spray rod. However, its disadvantage is that the oil circuit is complicated, and the inside of the spray rod is prone to coking and forming carbon deposits, which in turn blocks the oil circuit.

[0006] The Chinese invention patent application with application number 202211638301.8, entitled "An integrated air-cooled direct-injection spray bar", designs a cooling cavity between the spray bar body and the heat shield, and introduces cooling gas into the cooling cavity to isolate the spray bar body from the high-temperature combustion gas in the inner part, thereby effectively reducing the temperature of the spray bar body. However, its disadvantage is that the structural design does not improve the atomization performance of the spray bar, and the atomization effect is still poor. Summary of the invention

[0007] The purpose of the present invention is to provide a high-disturbance spray rod structure based on plasma excitation coupled pneumatic assisted atomization, so as to improve the fuel atomization performance and prevent the fuel in the oil delivery channel from coking at high temperature.

[0008] To achieve the above objectives, the technical solution of the present application is: a high disturbance spray bar structure based on plasma excitation coupled pneumatic assisted atomization, comprising:

[0009] A housing having an air inlet opening thereon;

[0010] A fuel pipeline having an oil delivery channel; the fuel pipeline extends into the housing and forms an air channel with the housing, the air channel being connected to the air inlet;

[0011] The first insulating platform has a collision atomization zone and an atomization development zone; the first insulating platform is connected to the output end of the fuel pipeline, and a plurality of oil and gas atomization channels are arranged at its neck;

[0012] The second insulating platform has a plasma discharge area, and the plasma discharge area is respectively connected with the atomization development area and the spray rod nozzle of the shell; the second insulating platform is clamped with the first insulating platform;

[0013] A high voltage electrode is located between the first insulating platform and the second insulating platform;

[0014] The grounding electrode is located between the second insulating platform and the shell.

[0015] As a preferred solution of the present invention, the output end of the fuel pipeline has an end fuel spray hole and a side fuel spray hole, wherein the end fuel spray hole is connected to the collision atomization area, and the side fuel spray hole is connected to the air channel.

[0016] As a preferred solution of the present invention, the fuel enters the fuel delivery channel from the fuel inlet, and then flows through the end face fuel spray holes and the side fuel spray holes respectively, and enters the combustion chamber in the form of oil mist.

[0017] As a preferred embodiment of the present invention, when the fuel is sprayed into the air channel from the side fuel spray hole, the fuel is mixed with the external air in the form of oil mist; the mixed oil-gas mixture is sprayed out through the oil-gas atomization channel of the upper insulating platform, and collides with the fuel liquid column sprayed from the fuel end face spray hole in the collision atomization zone, at which time the fuel is subjected to the aerodynamic force and collision effect of the oil-gas mixture.

[0018] As a preferred solution of the present invention, external air flows from the air inlet through the air channel into the oil-gas atomization channel, and is mixed with the fuel sprayed from the end face fuel spray hole in the collision atomization zone.

[0019] As a preferred solution of the present invention, the oil-gas mixture further formed in the collision atomization zone continuously develops along the flow direction of the airflow, and the fuel droplets and the oil-gas mixture pass through the atomization development zone to form a homogeneous mixture.

[0020] As a preferred embodiment of the present invention, when the homogeneous mixed gas flows through the plasma discharge area, the plasma power supply is turned on, and a dielectric barrier discharge is formed between the high-voltage electrode and the ground electrode. The plasma generated by the discharge contains a large number of active particles and high-energy electrons. The chemical effects of the active particles and high-energy electrons cause the fuel droplets to further break into smaller droplets, thereby forming a plasma-excited homogeneous mixed gas that is ejected from the nozzle of the spray rod.

[0021] As a preferred solution of the present invention, a plasma-excited mixed gas carrying a large amount of active particles and high-energy electrons enters the combustion chamber in the form of a spray.

[0022] As a preferred solution of the present invention, the clamping platform at the output end of the fuel pipeline extends into the groove of the first insulating platform.

[0023] As a preferred solution of the present invention, the fuel pipeline is installed on the housing through a fixing seat, and a through hole is opened on the fixing seat for the fuel pipeline to pass through.

[0024] The present invention adopts the above technical solution, and can achieve the following technical effects:

[0025] (1) By coupling plasma excitation with pneumatically assisted atomization and cross-collision, the fuel spray is subjected to three consecutive actions, thereby improving the fuel atomization performance of the high-turbation spray boom.

[0026] (2) In order to prevent the fuel in the oil delivery channel from coking at high temperatures, outside air is introduced so that the entire spray boom is cooled by the airflow.

[0027] (3) The air plasma discharge method can generate a large number of active particles. These active particles are sprayed into the combustion chamber together with the fuel spray, which can not only improve the ignition performance and combustion efficiency of the fuel spray, but also enhance its combustion stability. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. 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 paying any creative work.

[0029] Figure 1 A cross-sectional view of a high-disturbance boom structure based on plasma excitation coupled with pneumatically assisted atomization;

[0030] Figure 2 This is a partial enlarged view of the atomization process of a high-disturbance boom structure based on plasma excitation coupled pneumatic assisted atomization;

[0031] Figure 3 It is a schematic diagram of the circuit connection of the high disturbance boom structure based on plasma excitation coupled pneumatic assisted atomization;

[0032] Figure 4 A three-dimensional schematic diagram of the high-turbation spray boom structure based on plasma excitation coupled pneumatic assisted atomization.

[0033] Explanation of the serial numbers in the figure: 1 fuel inlet, 2 end cover, 3 outer shell, 4 first insulating platform, 5 high-voltage electrode, 6 grounding electrode, 7 second insulating platform, 8 air inlet, 9 fixing seat, 10 fuel pipeline, 11 oil delivery channel, 12 end face fuel spray hole, 13 collision atomization zone, 13 collision atomization zone, 14 atomization development zone, 15 active particles, 16 spray rod nozzle, 17 plasma discharge area, 18 oil and gas atomization channel, 19 air channel, 20 side fuel spray hole. DETAILED DESCRIPTION

[0034] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0035] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it can be directly on the other element or indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or indirectly connected to the other element.

[0036] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, "multiple" means two or more, unless otherwise clearly and specifically defined. "Several" means one or more, unless otherwise clearly and specifically defined.

[0037] In the description of the present application, it should be understood that the terms "center", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0038] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0039] In view of the problems in the prior art, such as low atomization performance of the fuel spray bar, high ambient temperature of the spray bar causing the fuel in the spray bar to coke easily, difficulty in ignition in the afterburner, and low combustion efficiency, this embodiment provides a high-disturbance spray bar structure based on plasma excitation coupled pneumatic assisted atomization, such as Figure 1 As shown, including:

[0040] The housing may be made of metal material, with an air inlet opening thereon and a spray bar nozzle at the output end;

[0041] The fuel pipeline can be made of metal material and has an oil delivery channel; the fuel pipeline extends into the shell and forms an air channel with the shell, and the air channel is connected to the air inlet; the output end of the fuel pipeline has an end face fuel spray hole and a side face fuel spray hole, wherein the end face fuel spray hole is connected to the collision atomization area, and the side face fuel spray hole is connected to the air channel;

[0042] The first insulating platform can be made of high temperature resistant insulating materials such as ceramics, and has a collision atomization zone and an atomization development zone; a clamping platform at the output end of the fuel pipeline is embedded in the groove of the first insulating platform, and a plurality of oil and gas atomization channels are arranged on its neck;

[0043] The second insulating platform can also be made of high temperature resistant insulating materials such as ceramics, and has a plasma discharge area, which is respectively connected to the atomization development area and the spray rod nozzle of the shell; the second insulating platform is clamped with the first insulating platform;

[0044] A high voltage electrode is located between the first insulating platform and the second insulating platform;

[0045] a grounding electrode, located between the second insulating platform and the housing;

[0046] The fixing seat is arranged at the end of the shell, and a through hole is opened on the fixing seat for the fuel pipeline to pass through, so as to impose circumferential and axial constraints on the fuel pipeline 10 to ensure a good fit between the fuel pipeline 10 and the first insulating platform 4.

[0047] The end cover is arranged on one side of the fixing seat, and a through hole is opened on the end cover for the fuel pipeline to pass through. The fastener passes through the end cover and the fixing seat and is connected with the shell.

[0048] like Figure 2 As shown, the fuel enters the fuel delivery channel 11 from the fuel inlet 1, and then flows through the end fuel spray hole 12 and the side fuel spray hole 20, and enters the combustion chamber in the form of oil mist. When the fuel is sprayed into the air channel 19 from the side fuel spray hole 12, the fuel will be mixed with the external air in the form of oil mist; the mixed primary oil-gas mixture is then sprayed out through the oil-gas atomization channel 18 in the first insulating platform 4, and collides with the fuel liquid column sprayed from the fuel end spray hole 12 in the collision atomization area 13, so that the fuel can be stimulated by the dual aerodynamic force of the oil-gas mixture and the collision effect, which can not only ensure a good atomization effect of the fuel, but also further enhance the mixing of the fuel droplets and the air.

[0049] External air flows from the air inlet through the air channel into the oil-gas atomization channel, and mixes with the fuel sprayed from the end fuel spray hole in the collision atomization area. During the entire working process, the external air can not only cool the spray rod to prevent the fuel from coking in the spray rod, but also use the aerodynamic effect of the external air at high speed to achieve the purpose of pneumatic atomization, and also provide carrier gas for plasma discharge.

[0050] The oil-gas mixture sprayed from the oil-gas atomization channel 18 collides with the fuel sprayed from the end fuel injection hole 12, and the oil-gas mixture further formed in the collision atomization area 13 continues to develop along the flow direction of the airflow; the fuel droplets and the oil-gas mixture flow through the atomization development area 14, at which time the two have been fully mixed to form a good homogeneous mixture and further develop downward; when the homogeneous mixture flows through the plasma discharge area 17, the plasma power supply is turned on, such as Figure 3As shown, a dielectric barrier discharge is formed between the high-voltage electrode 5 and the ground electrode 6. There are a large number of active particles 15 and high-energy electrons in the plasma generated by the discharge. The chemical effect of the active particles 15 and the high-energy electrons further breaks the fuel droplets into smaller droplets, thereby forming a plasma-stimulated homogeneous mixed gas; the plasma-stimulated homogeneous mixed gas is ejected from the nozzle 16 of the spray rod. At this time, the particle size of the fuel droplets of the plasma homogeneous mixed gas is very small. Due to the effect of the plasma thermal effect, the evaporation process on the surface of the fuel droplets is accelerated. At the same time, the mixed gas also carries a large number of active particles 15 and high-energy electrons. The problem of poor excitation effect on the insufficiently atomized fuel liquid column when the low-temperature plasma is used alone to excite the fuel atomization is solved. In a limited space, the fuel is broken step by step from the liquid column into small droplets that can be excited by the dielectric barrier discharge plasma, and then through the excitation of the plasma, the plasma-stimulated mixed gas with good atomization performance is finally ejected, thereby achieving the purpose of improving the ignition characteristics and combustion performance.

[0051] When the plasma-excited mixed gas carrying a large number of active particles and high-energy electrons enters the combustion chamber in the form of spray, its good atomization state and the presence of active particles can effectively improve the ignition performance of the engine and ensure the combustion performance of the fuel. A large number of active particles are generated by low-temperature plasma discharge, and the generated active particles can be used to assist in fuel atomization. The generated active particles are also sprayed into the combustion chamber together with the fuel spray to improve the ignition performance and combustion efficiency of the fuel spray.

[0052] like Figure 4 As shown, the present invention couples plasma excitation with pneumatic assisted atomization and cross collision to perform three consecutive actions on the fuel spray, thereby improving the fuel atomization performance of the high-disturbance spray rod; the active particles generated by plasma discharge can greatly improve the ignition performance and combustion stability of the fuel spray.

[0053] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A high-disturbance spray boom structure based on plasma excitation coupled pneumatic assisted atomization, characterized in that: include: A housing having an air inlet opening thereon; A fuel pipeline having a fuel delivery passage; The fuel pipeline extends into the housing and forms an air passage between the fuel pipeline and the housing, and the air passage is connected with the air inlet; The first insulating platform has a collision atomization zone and an atomization development zone; the first insulating platform is connected to the output end of the fuel pipeline, and a plurality of oil and gas atomization channels are arranged at its neck; The second insulating platform has a plasma discharge area, and the plasma discharge area is respectively connected with the atomization development area and the spray rod nozzle of the shell; the second insulating platform is clamped with the first insulating platform; A high voltage electrode is located between the first insulating platform and the second insulating platform; The grounding electrode is located between the second insulating platform and the shell.

2. According to claim 1, a high disturbance spray boom structure based on plasma excitation coupled pneumatic assisted atomization is characterized in that: The output end of the fuel pipeline is provided with an end face fuel spray hole and a side face fuel spray hole, wherein the end face fuel spray hole is communicated with the collision atomization zone, and the side face fuel spray hole is communicated with the air channel.

3. According to claim 2, a high disturbance spray bar structure based on plasma excitation coupled pneumatic assisted atomization is characterized in that: The fuel enters the fuel delivery channel from the fuel inlet, and then flows through the end face fuel spray holes and the side fuel spray holes respectively, and enters the combustion chamber in the form of oil mist.

4. According to claim 2, a high disturbance spray boom structure based on plasma excitation coupled pneumatic assisted atomization is characterized in that: When the fuel is sprayed into the air channel from the side fuel spray hole, the fuel is mixed with the external air in the form of oil mist; the mixed oil-gas mixture is sprayed out through the oil-gas atomization channel of the upper insulating platform, and collides with the fuel liquid column sprayed from the fuel end face spray hole in the collision atomization area. At this time, the fuel is affected by the aerodynamic force and collision of the oil-gas mixture.

5. According to claim 1, a high disturbance spray bar structure based on plasma excitation coupled pneumatic assisted atomization is characterized in that: External air flows from the air inlet through the air channel into the oil-gas atomization channel, and mixes with the fuel sprayed from the end face fuel spray hole in the collision atomization area.

6. According to claim 4, a high disturbance spray boom structure based on plasma excitation coupled pneumatic assisted atomization is characterized in that: The oil-gas mixture further formed in the collision atomization zone continues to develop along the flow direction of the airflow, and the fuel droplets and the oil-gas mixture pass through the atomization development zone to form a homogeneous mixture.

7. A high disturbance spray bar structure based on plasma excitation coupled pneumatic assisted atomization according to claim 6, characterized in that: When the homogeneous mixed gas flows through the plasma discharge area, the plasma power is turned on, and a dielectric barrier discharge is formed between the high-voltage electrode and the ground electrode. The plasma generated by the discharge contains a large number of active particles and high-energy electrons. The chemical effects of the active particles and high-energy electrons cause the fuel droplets to further break into smaller droplets, thereby forming a plasma-excited homogeneous mixed gas that is ejected from the nozzle of the spray boom.

8. According to claim 7, a high disturbance spray boom structure based on plasma excitation coupled pneumatic assisted atomization is characterized in that: The plasma-excited mixed gas carrying a large number of active particles and high-energy electrons enters the combustion chamber in the form of a spray.

9. The high disturbance spray boom structure based on plasma excitation coupled pneumatic assisted atomization according to claim 1, characterized in that: The clamping platform at the output end of the fuel pipeline extends into the groove of the first insulating platform.

10. The high disturbance spray boom structure based on plasma excitation coupled pneumatic assisted atomization according to claim 1, characterized in that: The fuel pipeline is installed on the shell through a fixing seat, and a through hole is opened on the fixing seat for the fuel pipeline to pass through.

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