Oil gas reverse rotation air atomizing nozzle matched with SAF

Abstract

The invention discloses an oil gas reverse rotation air atomizing nozzle matched with an SAF. The oil gas reverse rotation air atomizing nozzle comprises a center cone, a rotational flow chamber shell and an outer cover which are sequentially sleeved from inside to outside. An annular channel between the central cone and the rotational flow chamber shell is a tapered inner ring rotational flow chamber; a swirler is arranged at the inlet end of the inner ring swirl chamber; a fuel oil outlet which is arranged along the tangential direction is formed in the swirl chamber shell, and the swirl direction of the fuel oil outlet is opposite to that of the swirler; an annular channel between the rotational flow chamber shell and the outer cover is divided into an oil collecting cavity and an external flow rotational flow chamber; the oil collecting cavity is communicated with the inner ring rotational flow chamber through a fuel oil outlet; a plurality of outer ring air inlets are formed in the circumferential direction of the outer cover in the tangential direction, and the outflow rotational flow chamber communicates with the outside through the outer ring air inlets. According to the designed oil gas reverse rotation air atomizing nozzle, the mixing efficiency of fuel oil and air can be improved, the combustion process is optimized, and the heat efficiency and performance of an engine are improved; and the contact area between the SAF and the wall surface of the nozzle can be reduced, so that the influence of corrosion on a nozzle material is reduced.

Description

Technical Field

[0001] The invention relates to the technical field of fuel injection and atomization, and in particular to an oil-gas reverse cyclonic air atomization nozzle adapted to SAF. Background Art

[0002] As the source of aircraft power, aircraft engines are not only the key to driving flight, but also the vane of technological progress in the aviation industry. Every major breakthrough, such as the advent of turbojet engines, has profoundly influenced the history of human aviation. In this complex and sophisticated mechanical system, the fuel atomizing nozzle plays a vital role. It atomizes aviation kerosene, increases the contact area between fuel and air, accelerates the combustion process, optimizes combustion efficiency, and reduces pollutant emissions. Its importance is self-evident.

[0003] There are many types of nozzles, including direct injection, centrifugal, evaporative tube and air atomization, and each design strives to maintain high performance under extreme working conditions. In terms of material selection, stainless steel and titanium alloys have become the preferred materials for aircraft engine nozzles due to their excellent high temperature tolerance, mechanical strength and corrosion resistance.

[0004] However, with the urgent global demand for sustainable development, the aviation industry is facing an unprecedented transformation. Sustainable aviation fuel (SAF) has emerged as the times require. It uses biomass, waste, recycled oils and other raw materials, and can significantly reduce carbon emissions compared to traditional fuels, with a maximum reduction of 85%, becoming the cornerstone of the International Air Transport Association (IATA)'s 2050 net zero emission goal.

[0005] The emergence of SAF is not only an energy revolution, but also poses new challenges to existing aviation technology. Due to the differences in the physical and chemical properties of SAF and traditional fuels, the uniqueness of its viscosity and surface tension puts higher requirements on the atomization efficiency and material compatibility of fuel nozzles. The nozzle material must be able to withstand the chemical changes of SAF at high temperatures and maintain stability and durability.

[0006] In order to ensure seamless integration of SAF with existing aviation systems, it is particularly important to develop atomizing nozzles that are compatible with it. This is not only related to flight safety and efficiency, but also indicates innovative opportunities for aviation engine technology, which is expected to improve fuel efficiency, reduce emissions, and even stimulate further performance improvements. Summary of the invention

[0007] In order to address the deficiencies in the prior art, the present application proposes an oil-gas reverse cyclonic air atomizing nozzle adapted for SAF. The oil-gas reverse cyclonic air atomizing nozzle designed by the present invention can not only improve the mixing efficiency of fuel and air, optimize the combustion process, and improve the thermal efficiency and performance of the engine; it can also reduce the contact area between SAF and the nozzle wall, thereby reducing the impact of its corrosiveness on the nozzle material.

[0008] The technical solution adopted by the present invention is as follows:

[0009] An oil-gas reverse cyclonic air atomizing nozzle adapted for SAF comprises a central cone, a cyclonic chamber shell and an outer cover which are sequentially mounted from the inside to the outside;

[0010] The central cone is gradually expanding along the fluid flow direction;

[0011] The annular channel between the central cone and the swirl chamber shell is an inner ring swirl chamber, and the inner ring swirl chamber is tapered along the fluid flow direction;

[0012] A cyclone is installed at the inlet end of the inner ring cyclone chamber;

[0013] A plurality of fuel outlets are arranged tangentially on the circumference of the cyclone chamber housing, and the rotation direction of the fuel outlets is opposite to that of the cyclone;

[0014] The annular channel between the swirl chamber shell and the outer cover is divided into an oil collecting chamber and an outer flow swirl chamber; the oil collecting chamber is connected with the inner ring swirl chamber through the fuel outlet; the outer flow swirl chamber is tapered along the fluid flow direction;

[0015] A plurality of outer ring air inlets are arranged tangentially in the circumference of the outer cover, and the outer flow vortex chamber is communicated with the outside through the outer ring air inlets.

[0016] Further, at the outlet, the height difference between the central cone and the cyclone chamber shell is 1 mm, and the height difference between the cyclone chamber shell and the outer cover is 1 mm;

[0017] Furthermore, the angle between the inner side surface of the outer cover at the outlet and the outer side surface of the central cone is 17°.

[0018] Furthermore, the swirler includes a plurality of blades, and the bending angle of the blades is 20°-30°.

[0019] Furthermore, from the outside of the outer cover to the inside and outside, the outer ring air inlet is a downwardly inclined hole, and the deviation angle between the central axis of the outer ring air inlet and the central axis of the nozzle is 30° to 50°.

[0020] Furthermore, a partition plate is directly processed on the inner wall of the outer cover to directly separate the oil collecting chamber and the outflow cyclone chamber from the gap between the outer cover and the cyclone chamber shell.

[0021] Furthermore, an oil collecting groove is arranged between the outer cover and the outer shell of the cyclone chamber, and the oil collecting groove forms an annular oil collecting cavity between the outer wall surfaces of the outer shell of the cyclone chamber.

[0022] Furthermore, the fuel inlet is a tangential hole arranged along the tangential direction of the outer cover.

[0023] Furthermore, the diameter of the fuel inlet is 4 to 6 mm.

[0024] Furthermore, the diameter of the fuel outlet is 3 to 5 mm.

[0025] Beneficial effects of the present invention:

[0026] (1) The present invention adopts an oil-gas counter-swirl design to improve the atomization effect of fuel (including SAF).

[0027] (2) The fuel of the present invention is mainly atomized by high-speed air, and its fuel supply pressure envelope is relatively large, thereby ensuring the atomization effect in a small state.

[0028] (3) The present invention utilizes high-speed air in the outer ring tapered air chamber to increase the penetration distance of the oil droplets and make the oil droplets more evenly distributed.

[0029] (4) The present invention is suitable for use in SAF of aircraft engines and can also be used in other power devices using biofuels, and has certain versatility and practical value. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a schematic diagram of the longitudinal cross-sectional structure of an oil-gas reverse cyclonic air atomizing nozzle adapted to SAF of the present invention.

[0031] Figure 2 It is a schematic diagram of the transverse cross-sectional structure of an oil-gas reverse cyclonic air atomizing nozzle adapted to SAF of the present invention.

[0032] Figure 3 It is a schematic diagram of the cyclone structure of an oil-gas reverse cyclone air atomizing nozzle adapted to SAF of the present invention, wherein a is a side view, b is a front view, and c is an axial view.

[0033] Figure 4 It is a schematic diagram of the working principle of an oil-gas reverse cyclonic air atomizing nozzle adapted to SAF of the present invention.

[0034] Among them: 1. cyclone, 1-1. blades, 1-2. central ring structure, 1-3. external ring structure, 2. oil collecting tank, 3. cyclone chamber shell, 4. central cone, 5. outer cover, 6. inner ring cyclone chamber, 7. outer flow cyclone chamber, 8. outer ring air inlet, 9. fuel inlet, 10. fuel outlet, 11. inner ring air inlet. DETAILED DESCRIPTION

[0035] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention 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 invention and are not used to limit the present invention.

[0036] Reference Figures 1 to 4 The oil-gas reverse cyclone air atomizing nozzle adapted to SAF designed by the present invention comprises a cyclone 1, a cyclone chamber shell 3, a central cone 4, and an outer cover 5.

[0037] The central cone 4 is located in the middle, and its outer wall surface is gradually expanded along the fluid flow direction.

[0038] The swirl chamber shell 3 is mounted on the outside of the central cone 4, and the two are coaxially arranged; an annular channel is left between the inner wall surface of the swirl chamber shell 3 and the outer wall surface of the central cone 4 to form an inner ring swirl chamber 6, and the inner ring swirl chamber 6 is tapered along the fluid flow direction.

[0039] The cyclone 1 is arranged at the inlet end of the inner ring cyclone chamber 6, serving as the inner ring air inlet 11, for inputting cyclone into the inner ring cyclone chamber 6. In this embodiment, the structure of the cyclone 1 is as follows: Figure 3 As shown, it is composed of a central annular structure 1-2, an outer annular structure 1-3 and a plurality of blades 1-1. The central annular structure 1-2 and the outer annular structure 1-3 are coaxially arranged, and a plurality of blades 1-1 are evenly distributed between the central annular structure 1-2 and the outer annular structure 1-3. The blades 1-1 have a certain degree of curved surface bending, and the fluid can form a swirl after passing through the blades 1-1. A rotating shaft is set at the tip of the central cone 4, and the central annular structure 1-2 is mounted on the rotating shaft. The two can be threadedly connected, and the outer annular structure 1-3 is threadedly connected to the inner wall surface of the inlet side of the swirl chamber shell 3.

[0040] The outer cover 5 is mounted on the outside of the swirl chamber shell 3, and the two are arranged coaxially; a gap is left between the inner wall of the outer cover 5 and the outer wall of the swirl chamber shell 3; in this embodiment, the gap is divided into upper and lower parts, and the upper part of the gap is an oil collecting chamber. A fuel inlet 9 is opened on the outer cover 5 opposite to the oil collecting chamber, and a fuel outlet 10 is opened on the swirl chamber shell 3 opposite to the oil collecting chamber. The oil collecting chamber is connected to the external oil supply unit through the fuel inlet 9, and fuel is input into the oil collecting chamber. The fuel outlet 10 is arranged tangentially on the swirl chamber shell 3, and the rotation direction of the fuel outlet 10 is opposite to that of the swirler 1, so the fuel in the oil collecting chamber obtains the opposite swirl direction through the fuel outlet 10 and enters the inner ring swirl chamber 6.

[0041] The lower part of the gap is the outer flow swirl chamber 7, and the inner flow swirl chamber 7 is gradually contracted along the fluid flow direction; a plurality of outer ring air inlets 8 are arranged circumferentially on the outer cover 5, and the outer ring air inlets 8 are arranged tangentially, and air enters the outer flow swirl chamber 7 through the outer ring air inlets 8 to form outer ring swirl air.

[0042] In this embodiment, a partition plate is directly processed on the inner wall of the outer cover 5 to directly separate the oil collecting chamber and the outflow cyclone chamber 7 from the gap between the outer cover 5 and the cyclone chamber shell 3 .

[0043] In this embodiment, an oil collecting groove 2 may be further provided between the outer cover 5 and the cyclone chamber shell 3 , and the oil collecting groove 2 forms an annular oil collecting cavity between the outer wall surfaces of the cyclone chamber shell 3 .

[0044] In this embodiment, the fuel inlet 9 on the outer cover 5 is also a tangential hole with a diameter of 4 to 6 mm.

[0045] In this embodiment, the fuel outlet 10 is composed of 6 to 8 evenly distributed tangential holes, with a diameter of 3 to 5 mm, and the eccentric openings are all facing the oil collecting tank 2.

[0046] In this embodiment, 9 to 12 blades 1 - 1 of the cyclone 1 may be evenly arranged, and the bending angle of the blades 1 - 1 is 20° to 30°.

[0047] In this embodiment, 6 to 10 outer ring air inlets 8 can be evenly arranged on the outer cover 5, and the outer ring air inlet 8 is a downward inclined hole, and the deviation angle between the central axis of the outer ring air inlet 8 and the central axis of the nozzle is 30° to 50°.

[0048] In this embodiment, by adjusting the cone angle of the central cone 4, the atomization cone angle of the nozzle can be adjusted within the range of 40°-120°.

[0049] In this embodiment, the height difference between the central cone 4 and the cyclone chamber shell 3 is 1 mm, and the height difference between the cyclone chamber shell 3 and the outer cover 5 is 1 mm.

[0050] In this embodiment, the angle between the inner side surface of the outer cover 5 at the outlet and the outer side surface of the central cone 4 is 17°.

[0051] The working principle of the present invention is as follows: the fuel nozzle structure of the present invention can divide the incoming high-speed airflow into two paths, one path is supplied from the inner ring, and the other path is supplied from the outer ring. Among them, the high-speed air supplied from the inner ring air inlet 11 is given an initial angular momentum by the swirler 1, and is accelerated by the tapered inner ring swirl chamber 6 between the central cone 4 and the swirl chamber shell 3. At the same time, the fuel is input into the oil collecting chamber through the fuel inlet 9 on the outer cover 5, and the fuel in the oil collecting chamber enters the inner ring swirl chamber 6 through the fuel outlet 10 arranged tangentially on the swirl chamber shell 3. The fuel 6 entering the inner ring swirl chamber has an initial angular momentum opposite to that of the high-speed air, so that the air and the fuel achieve opposite swirl directions.

[0052] The high-speed air supplied by the outer ring enters the tapered outer flow swirl chamber 7 through the outer ring air inlet 8 arranged along the tangential direction for acceleration; the outer ring air led to the nozzle lip by the outer flow swirl chamber 7 is mixed with the oil-air mixture led to the nozzle lip by the inner ring. Due to the viscosity of the high-speed airflows on both sides and the strong shearing effect caused by the different directions of the two air paths, the oil droplets are further atomized and the oil mist is transported.

[0053] The present invention adopts the design of oil-gas counter-swirl to enhance the breaking effect of airflow on oil droplets, improve the atomization effect of fuel (including SAF), and help improve the mixing efficiency of fuel and air, thereby optimizing the combustion process and improving the thermal efficiency and performance of the engine.

[0054] In the present invention, the fuel is mainly atomized by high-speed air, so the atomization performance can be guaranteed at low fuel supply pressure. Compared with the centrifugal nozzle, the high-efficiency fuel supply pressure range is widened.

[0055] The present invention utilizes high-speed air in the outer ring tapered air chamber to increase the penetration distance of oil droplets and make the oil droplets more evenly distributed.

[0056] The present invention can reduce the contact area between the SAF and the nozzle wall through a special oil circuit design, thereby reducing the influence of its corrosiveness on the nozzle material.

[0057] The above embodiments are only used to illustrate the design ideas and features of the present invention, and their purpose is to enable those skilled in the art to understand the content of the present invention and implement it accordingly. The protection scope of the present invention is not limited to the above embodiments. Therefore, any equivalent changes or modifications made based on the principles and design ideas disclosed by the present invention are within the protection scope of the present invention.

Claims

1. An oil-gas reverse cyclonic air atomizing nozzle adapted to SAF, characterized in that: It comprises a central cone (4), a cyclone chamber shell (3), and an outer cover (5) which are sequentially mounted from the inside to the outside; The central cone (4) is gradually expanding along the fluid flow direction; The annular channel between the central cone (4) and the cyclone chamber shell (3) is an inner ring cyclone chamber (6), and the inner ring cyclone chamber (6) is tapered along the fluid flow direction; A cyclone (1) is installed at the inlet end of the inner ring cyclone chamber (6); A plurality of fuel outlets (10) are arranged tangentially on the circumference of the cyclone chamber housing (3), and the rotation direction of the fuel outlets (10) is opposite to the rotation direction of the cyclone (1); The annular channel between the swirl chamber shell (3) and the outer cover (5) is divided into an oil collecting chamber and an outer flow swirl chamber (7); the oil collecting chamber is connected to the inner ring swirl chamber (6) through the fuel outlet (10); the outer flow swirl chamber (7) is tapered along the fluid flow direction; A plurality of outer ring air inlets (8) are arranged tangentially in the circumference of the outer cover (5), and the outer flow vortex chamber (7) is connected to the outside through the outer ring air inlets (8).

2. The oil-gas reverse cyclonic air atomizing nozzle adapted to SAF according to claim 1, characterized in that: The swirler (1) comprises a plurality of blades (1-1), and the bending angle of the blades (1-1) is 20°-30°.

3. The oil-gas reverse cyclonic air atomizing nozzle adapted to SAF according to claim 1, characterized in that: From the outside of the outer cover (5) to the inside and outside, the outer ring air inlet (8) is a downwardly inclined hole, and the deflection angle between the central axis of the outer ring air inlet (8) and the central axis of the nozzle is 30° to 50°.

4. The oil-gas reverse cyclonic air atomizing nozzle adapted to SAF according to claim 1, characterized in that: A partition plate is directly processed on the inner wall of the outer cover (5), so that the gap between the outer cover (5) and the cyclone chamber shell (3) is directly separated into an oil collecting chamber and an outflow cyclone chamber (7).

5. The oil-gas reverse cyclonic air atomizing nozzle adapted to SAF according to claim 1, characterized in that: An oil collecting groove (2) is arranged between the outer cover (5) and the cyclone chamber shell (3), and the oil collecting groove (2) forms an annular oil collecting cavity between the outer wall surfaces of the cyclone chamber shell (3).

6. The oil-gas reverse cyclonic air atomizing nozzle adapted to SAF according to claim 1, characterized in that: The fuel inlet (9) is a tangential hole and is arranged along the tangential direction of the outer cover (5).

7. The oil-gas reverse cyclonic air atomizing nozzle adapted to SAF according to claim 1, characterized in that: The diameter of the fuel inlet (9) is 4-6 mm.

8. The oil-gas reverse cyclonic air atomizing nozzle adapted to SAF according to claim 1, characterized in that: The diameter of the fuel outlet (10) is 3-5 mm.

9. The oil-gas reverse cyclonic air atomizing nozzle adapted to SAF according to claim 1, characterized in that: The height difference between the central cone (4) and the cyclone chamber shell (3) is 1 mm, and the height difference between the cyclone chamber shell (3) and the outer cover (5) is 1 mm.

10. The oil-gas reverse cyclonic air atomizing nozzle adapted to SAF according to claim 1, characterized in that: The angle between the inner side surface of the outer cover (5) at the outlet and the outer side surface of the central cone (4) is 17°.

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