Afterburner cyclone nozzle

Abstract

The invention belongs to the field of afterburners of aero-engines, and particularly relates to a cyclone nozzle of an afterburner. The cyclone nozzle comprises a nozzle body, a fuel oil channel and a gas channel are formed in the nozzle body, the fuel oil channel is provided with a fuel oil channel outlet, and a containing cavity located at the fuel oil channel outlet is formed in the nozzle body; the pressure difference floating seat is accommodated in the accommodating cavity; the fuel quantity control valve is fixedly installed on the nozzle body, located in the containing cavity and used for fuel flow control. The nozzle opening is formed in the nozzle main body, and the nozzle opening is communicated with the containing cavity through a nozzle opening channel; the cyclone channel is formed in the nozzle body, an air inlet of the cyclone channel is communicated with the air channel, and an air outlet of the cyclone channel is communicated with the nozzle channel.

Description

Technical Field

[0001] This application belongs to the field of afterburners for aero engines, and specifically relates to an afterburner cyclone nozzle. Background Technology

[0002] To meet the ever-increasing thrust requirements of aero-engines, afterburners need to inject more fuel for combustion at higher background temperatures, which easily leads to coking and clogging of the afterburner nozzles. At the same time, the increasingly larger flight envelope of aero-engine afterburners also results in greater variations in background airflow velocity during operation, posing significant challenges to fuel atomization and combustion organization.

[0003] As aero-engines expand their flight envelopes and demand higher aero-thermal performance, the direct-injection nozzles used in afterburners currently face two main challenges. First, the increasing gas temperature within the afterburner leads to a higher risk of coking in the fuel within the injection pipe, and fuel dripping after afterburner shutdown poses a risk of spontaneous combustion. Second, the operating environment of the afterburner becomes more severe with the expanding flight envelope of aero-engines, making it crucial to effectively manage fuel atomization and achieve optimal air-fuel mixing and combustion under low back pressure and high flow velocity conditions.

[0004] Therefore, there is an urgent need for a technical solution to overcome or mitigate at least one of the aforementioned defects in the existing technology. Summary of the Invention

[0005] The purpose of this application is to provide an afterburner cyclone nozzle to solve the problems of coking and poor atomization in existing aero-engine afterburner nozzles.

[0006] The technical solution of this application is: An afterburner cyclone nozzle, comprising: The nozzle body has a fuel passage and a gas passage inside, the fuel passage has a fuel passage outlet, and the nozzle body has a receiving cavity located at the fuel passage outlet; A differential pressure floating seat, which is housed inside the receiving cavity; A fuel flow control valve is fixedly mounted on the nozzle body and located inside the receiving cavity, and is used for fuel flow control. The nozzle is formed on the nozzle body and communicates with the receiving cavity through a nozzle channel; A cyclone channel is provided on the nozzle body. The air inlet of the cyclone channel is connected to the gas channel, and the air outlet is connected to the nozzle channel.

[0007] In at least one embodiment of this application, the cross-sections of both the receiving cavity and the differential pressure floating seat are trapezoidal.

[0008] In at least one embodiment of this application, multiple oil quantity control valves are evenly distributed circumferentially along the central axis of the nozzle channel.

[0009] In at least one embodiment of this application, a plurality of cyclone channels are evenly distributed circumferentially along the central axis of the nozzle channel.

[0010] In at least one embodiment of this application, the outlet of the cyclone channel is tangent to the wall of the nozzle channel.

[0011] In at least one embodiment of this application, the nozzle channel adopts a scaling structure.

[0012] In at least one embodiment of this application, the cyclone channel adopts a straight-mouth structure.

[0013] In at least one embodiment of this application, the outlet of the cyclone channel is located upstream of the critical cross section of the nozzle channel.

[0014] In at least one embodiment of this application, the cyclone nozzle has a first operating state and a second operating state; First working state: When the afterburner is not working, no fuel enters the fuel passage, but bypass gas enters the gas passage. The bypass gas in the gas passage enters the nozzle passage through the cyclone passage. The gas pressure is greater than the fuel pressure. Under the action of the gas pressure, the differential pressure float disengages from the fuel quantity control valve and closes the fuel passage outlet of the fuel passage. Second working state: When the afterburner is in operation, fuel enters the fuel passage and bypass gas enters the gas passage. The bypass gas in the gas passage enters the nozzle passage through the cyclone passage. When the fuel pressure is greater than the gas pressure, the differential pressure float is pushed open by the fuel pressure until the differential pressure float abuts the fuel quantity control valve. After the fuel in the fuel passage is injected into the nozzle passage through the receiving cavity, it is affected by the bypass gas from the cyclone passage and obtains a tangential velocity component that rotates around the central axis of the nozzle passage.

[0015] The invention has at least the following beneficial technical effects: The afterburner cyclone nozzle of this application can effectively cut off the contact between fuel and air in the fuel injection pipe when the afterburner is not working, and can prevent fuel from remaining in the nozzle and causing coking or dripping onto the surface of the afterburner flow channel components and spontaneously combusting. When the afterburner is working, the fuel in the cyclone nozzle can obtain higher turbulent kinetic energy under the action of swirling gas and break into smaller droplets, which promotes the entrainment of gas by fuel and improves the atomization effect. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the afterburner cyclone nozzle in the first working state of one embodiment of this application; Figure 2 This is a schematic diagram of the afterburner cyclone nozzle in the second working state of one embodiment of this application.

[0017] in: 1-Fuel passage; 2-Gas passage; 3-Differential pressure float seat; 4-Fuel quantity control valve; 5-Swirl passage; 6-Injector. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions in the embodiments of this application will be described in more detail below with reference to the accompanying drawings. In the drawings, the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The described embodiments are some, but not all, embodiments of this application. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this application, and should not be construed as limiting this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application. The embodiments of this application will be described in detail below with reference to the accompanying drawings.

[0019] In the description of this application, it should be understood that the terms "center", "longitudinal", "lateral", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting the scope of protection of this application.

[0020] The following is in conjunction with the appendix Figures 1 to 2 This application will be described in further detail.

[0021] This application provides an afterburner cyclone nozzle, including: a fuel passage 1, a gas passage 2, a cyclone passage 5, and an nozzle 6 on the nozzle body, as well as a differential pressure floating seat 3 and a fuel quantity control valve 4.

[0022] The nozzle body contains a fuel passage 1 and a gas passage 2. Fuel in fuel passage 1 originates from the fuel mains, while gas in gas passage 2 originates from the bypass gas. Fuel passage 1 and gas passage 2 are not directly connected. Fuel passage 1 has a fuel passage outlet, and a receiving cavity is located at the fuel passage outlet on the nozzle body. A differential pressure float 3 is housed within this cavity and positioned between fuel passage 1 and the nozzle channel to control the flow of fuel between them. A fuel flow control valve 4 is fixedly mounted on the nozzle body and located within the receiving cavity. This valve controls fuel flow and prevents the differential pressure float 3 from blocking the nozzle channel during afterburner operation. A nozzle 6 is located on the nozzle body and connects to the receiving cavity via a nozzle channel. A cyclone channel 5 is also located on the nozzle body. The inlet of the cyclone channel 5 connects to gas passage 2, and the outlet connects to the nozzle channel.

[0023] In a preferred embodiment of this application, both the receiving cavity and the differential pressure floating seat 3 have trapezoidal cross-sections. Preferably, multiple oil quantity control valves 4 are evenly distributed circumferentially along the central axis of the nozzle channel on the nozzle body at the bottom of the receiving cavity.

[0024] In a preferred embodiment of this application, multiple cyclone channels 5 are evenly distributed circumferentially along the central axis of the nozzle channel on the nozzle body, and 2 to 8 channels can be provided. In this embodiment, 6 cyclone channels 5 are provided. The central axis of the cyclone channel 5 can be coplanar with the central axis of the nozzle channel, or it can be not in the same plane as the central axis of the nozzle channel, forming an eccentric structure. The cyclone channel 5 can be tangentially connected to the wall of the nozzle channel, or it can be perpendicularly connected to the wall of the nozzle channel. In this embodiment, the air outlet of the cyclone channel 5 is tangential to the wall of the nozzle channel.

[0025] The afterburner cyclone nozzle of this application has a cyclone channel 5 that can be a tapered or straight-mouth structure, and an nozzle channel that can be a dipping, expanding, or straight-mouth structure. In a preferred embodiment of this application, the nozzle channel adopts a expanding structure, including a straight section near the receiving cavity and a flared section near the nozzle 6, with a critical cross-section between the straight section and the flared section. The cyclone channel 5 adopts a straight-mouth structure. In this embodiment, the outlet of the cyclone channel 5 is located upstream of the critical cross-section of the nozzle channel.

[0026] The afterburner cyclone nozzle of this application has a first working state and a second working state.

[0027] like Figure 1 As shown, in the first working state: When the afterburner is not working, no fuel enters the fuel passage 1, and external gas enters the gas passage 2. The external gas in the gas passage 2 enters the nozzle passage through the cyclone passage 5. The gas pressure is greater than the fuel pressure. Under the action of the gas pressure, the differential pressure float 3 disengages from the fuel quantity control valve 4 and closes the fuel passage outlet of the fuel passage 1. like Figure 2 As shown, in the second working state: When the afterburner is working, fuel enters the fuel passage 1 and bypass gas enters the gas passage 2. The bypass gas in the gas passage 2 enters the nozzle passage through the cyclone passage 5. When the fuel pressure is greater than the gas pressure, the differential pressure float 3 is pushed open by the fuel pressure until the differential pressure float 3 abuts the fuel quantity control valve 4. After the fuel in the fuel passage 1 is injected into the nozzle passage through the receiving cavity, it is affected by the bypass gas from the cyclone passage 5 and obtains a tangential velocity component that rotates around the central axis of the nozzle passage.

[0028] In this application, when the afterburner is not operating, no fuel enters the fuel passage 1 of the cyclone nozzle from the injection pipe. Instead, external gas flows in the gas passage 2 of the cyclone nozzle and enters the nozzle passage through the cyclone passage 5. At this time, the pressure of this gas is higher than the fuel pressure in the fuel passage 1. Under the action of the gas pressure, the differential pressure float 3 disengages from the fuel quantity control valve 4, completely sealing the fuel passage outlet. The fuel in the fuel passage 1 is isolated from the external gas, which not only prevents coking and spontaneous combustion due to the influence of high-temperature gas, but also prevents it from dripping from the nozzle 6 onto the afterburner flow path components. Furthermore, since gas is constantly being blown out from the cyclone passage 5 in the nozzle passage, it can provide effective gas-cooling protection for the cyclone nozzle and keep the nozzle 6 clean.

[0029] The afterburner cyclone nozzle of this application, when the afterburner starts working, fuel enters the fuel passage 1 from the injection pipe and establishes a certain fuel supply pressure. When the fuel pressure is higher than the gas pressure in the gas passage 2, the differential pressure float 3 is pushed open by the fuel until the differential pressure float 3 reaches the fuel quantity control valve 4 (i.e., the opening reaches its maximum). After the fuel is injected into the nozzle passage, it is affected by the gas from the cyclone passage 5, and obtains a tangential velocity component rotating around the central axis of the nozzle passage, greatly increasing the turbulent kinetic energy. As a result, the fuel can complete one droplet breakup, forming small droplet particles with higher turbulent kinetic energy and tangential velocity. These droplet particles, after being ejected, not only obtain a larger spray cone angle and tangential velocity, but also have a shorter breakup time, and can quickly form smaller droplets. This effectively increases the fuel-gas contact area, enhances the fuel's entrainment of gas, shortens the fuel-gas mixing time, and improves the fuel-gas mixture quality.

[0030] The afterburner cyclone nozzle of this application has been verified by bench tests on an afterburner model: compared with the traditional direct-injection nozzle, this afterburner cyclone nozzle can reduce the SMD (Soder Mean Diameter) of fuel droplets by 35%, improve the combustion efficiency of the afterburner by 6%, and increase the total outlet temperature by 80K, which significantly improves the fuel atomization effect and enhances the combustion performance of the afterburner.

[0031] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A cyclone nozzle for an afterburner, characterized in that, include: The nozzle body has a fuel passage (1) and a gas passage (2) inside. The fuel passage (1) has a fuel passage outlet. The nozzle body has a receiving cavity located at the fuel passage outlet. Differential pressure floating seat (3), the differential pressure floating seat (3) is housed inside the receiving cavity; Fuel flow control valve (4), which is fixedly installed on the nozzle body and located inside the receiving cavity, is used for fuel flow control; The nozzle (6) is formed on the nozzle body and is connected to the receiving cavity through the nozzle channel; Cyclone channel (5) is formed on the nozzle body. The air inlet of the cyclone channel (5) is connected to the gas channel (2), and the air outlet is connected to the nozzle channel.

2. The afterburner cyclone nozzle according to claim 1, characterized in that, The cross-sections of both the receiving cavity and the differential pressure floating seat (3) are trapezoidal.

3. The afterburner cyclone nozzle according to claim 2, characterized in that, Multiple oil quantity control valves (4) are evenly distributed circumferentially along the central axis of the nozzle channel.

4. The afterburner cyclone nozzle according to claim 1, characterized in that, The cyclone channels (5) are evenly distributed around the central axis of the nozzle channel.

5. The afterburner cyclone nozzle according to claim 4, characterized in that, The outlet of the cyclone channel (5) is tangent to the wall of the nozzle channel.

6. The afterburner cyclone nozzle according to claim 1, characterized in that, The nozzle channel adopts a scaling structure.

7. The afterburner cyclone nozzle according to claim 6, characterized in that, The cyclone channel (5) adopts a straight-mouth structure.

8. The afterburner cyclone nozzle according to claim 7, characterized in that, The outlet of the cyclone channel (5) is located upstream of the critical section of the nozzle channel.

9. The afterburner cyclone nozzle according to claim 1, characterized in that, The cyclone nozzle has a first working state and a second working state; First working state: When the afterburner is not working, no fuel enters the fuel passage (1), and external gas enters the gas passage (2). The external gas in the gas passage (2) enters the nozzle passage through the cyclone passage (5). The gas pressure is greater than the fuel pressure. The differential pressure float (3) disengages from the fuel quantity control valve (4) under the action of the gas pressure, thus closing the fuel passage outlet of the fuel passage (1). Second working state: When the afterburner is working, fuel enters the fuel passage (1) and bypass gas enters the gas passage (2). The bypass gas in the gas passage (2) enters the nozzle passage through the cyclone passage (5). When the fuel pressure is greater than the gas pressure, the differential pressure float (3) is pushed open by the fuel pressure until the differential pressure float (3) abuts the fuel quantity control valve (4). After the fuel in the fuel passage (1) is injected into the nozzle passage through the receiving cavity, it is affected by the bypass gas from the cyclone passage (5) and obtains a tangential velocity component that rotates around the central axis of the nozzle passage.

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