Flame tube head adjusting device and aero-engine

Abstract

This invention discloses a flame tube head adjustment device and an aero-engine, including a connecting cover plate, a venturi tube, a vortex generator, a fuel nozzle, and an elastic element. The connecting cover plate is connected to the end of the venturi tube facing the fuel nozzle, forming an adjustment cavity. The vortex generator is sleeved outside the fuel nozzle, and its end facing the venturi tube is movably positioned within the adjustment cavity. Air holes are provided on the wall of the fuel nozzle. The elastic element is positioned between the venturi tube and the vortex generator to apply an elastic force to the vortex generator, causing it to move away from the venturi tube. Compared with existing technologies, this solution results in a smoother change in the air intake volume at the flame tube head, stable combustion chamber operation during switching of working states, and the elastic element being located away from the main combustion zone of the flame tube. The adjustment device exhibits high reliability during long-term operation under harsh thermal environments. It achieves coordinated adjustment of the fuel-air ratio and atomization cone angle, more effectively widening the ignition and quenching envelope of the combustion chamber and improving combustion chamber performance. It is highly practical and suitable for widespread promotion and application.

Description

Technical Field

[0001] This invention relates to the field of aero-engine technology, and in particular, to a flame tube head adjustment device and an aero-engine. Furthermore, this invention also relates to an aero-engine including the aforementioned flame tube head adjustment device and aero-engine. Background Technology

[0002] The ignition and extinction envelopes of the combustion chamber are a collective term for the ignition and extinction envelopes, which respectively define the limits of the combustion chamber's ability to successfully ignite the flame and maintain stable combustion. Typically, the ignition envelope is narrower than the extinction envelope, meaning that under certain operating conditions, the engine may be able to maintain combustion but cannot reignite it. This difference is an important indicator of combustion stability.

[0003] For the following reasons, aero-engines generally have wide requirements for the ignition / quench envelope of the combustor: In terms of flight safety, airworthiness standards have strict requirements for in-flight restart capability; the ability to reliably restart after an in-flight engine shutdown directly affects flight safety. At high altitudes, inlet air pressure and temperature decrease significantly, fuel atomization quality deteriorates, and the minimum ignition fuel-air ratio and lean quench fuel-air ratio increase rapidly, resulting in weak starting capability. At high speeds, the inlet airflow velocity of the combustor is high, making flame stabilization difficult. Therefore, widening the ignition / quench envelope is a key technical objective in combustor design.

[0004] The air-fuel ratio and the fuel nozzle atomization cone angle are two main factors determining the ignition / quench envelope. To broaden the ignition / quench envelope, an ideal design requires coordinated adjustment of both the air-fuel ratio and the atomization cone angle: under low-pressure conditions, reducing the head air volume creates a localized rich fuel zone, and a larger atomization cone angle makes it easier for the atomized fuel to contact the ignition spark, improving ignition performance; under high-pressure conditions, increasing the head air volume reduces the air-fuel ratio, and decreasing the atomization cone angle shrinks the main combustion zone, which helps reduce the temperature at the flame tube head. However, traditional combustion chambers have fixed head air intake areas and nozzle structures, making it impossible to adjust the air volume or atomization cone angle according to operating conditions. This results in excessive air intake and a low air-fuel ratio at the head, leading to lean-fuel quenching under low-pressure conditions, while insufficient air intake and a high air-fuel ratio under high-pressure conditions cause severe smoke. Furthermore, a single fixed cone angle cannot meet the matching requirements of all operating conditions. This contradiction between smoke under high-pressure conditions and lean-fuel quenching under low-pressure conditions, as well as the conflict between a fixed cone angle and the wide-range matching requirements, constitutes the main technical bottleneck restricting the broadening of the ignition / quench envelope.

[0005] To address the aforementioned problems, Chinese invention patent application CN120506667A discloses a combustion chamber, including a flame tube head, a flame tube outer ring, a flame tube inner ring, and a fuel nozzle. A sliding sleeve is provided on the outer side of the flame tube head. A swirl assembly is slidably mounted on the outer surface of the fuel nozzle near one end of the flame tube. The sliding sleeve is slidably mounted on the outer surface of the swirl assembly. A first swirl and a second swirl are provided on the swirl assembly. An air intake groove is provided on the sliding sleeve, which can be connected to or disconnected from the second swirl. This solution achieves adaptive adjustment of the air intake volume through the sliding sleeve: in the low-pressure state, the sliding sleeve is closed, and only the first swirl intakes air, creating a locally high air-fuel ratio at the head, improving ignition and lean-fuel-to-shutdown performance at idle; in the high-pressure state, the sliding sleeve opens under the action of pressure difference, allowing both the first and second swirls to intake air simultaneously, increasing the air volume at the head, reducing the overall air-fuel ratio, and solving the smoke problem.

[0006] However, this existing technical solution still has the following problems: First, the flow rate of the second vortex is usually around 6%, and the intake volume of the second vortex accounts for a large proportion of the total intake volume. During the switching between small and large states, when the sliding sleeve adjusts the intake channel of the second vortex, even a small change in opening can cause a large change in the intake volume, resulting in a drastic fluctuation in the air-fuel ratio at the head, which can easily lead to unstable combustion chamber operation and consequently, unstable engine operation. Second, the reset of the sliding sleeve usually relies on an elastic element, which is located near the main combustion zone at the head of the flame tube. This area has extremely high temperatures, and the elastic element is prone to loosening or failure after long-term service in a high-temperature environment, resulting in the sliding sleeve not being able to reset reliably, affecting the reliability of combustion chamber operation. Third, this solution only changes the air-fuel ratio at the head by adjusting the air flow rate and does not involve the adjustment of the fuel nozzle atomization cone angle. When the operating conditions change over a wide range, the fixed atomization cone angle is difficult to achieve optimal matching with the changing airflow field across the entire operating range, and there is still room for further improvement in widening the flameout envelope.

[0007] In summary, the existing solution is prone to causing abrupt fluctuations in the air-fuel ratio and combustion instability in terms of adjustment method; in terms of structural reliability, the elastic components face the risk of high-temperature failure; and in terms of adjustment dimension, it only involves the adjustment of the vortex air volume and not the adjustment of the atomization cone angle, failing to achieve coordinated matching between the air-fuel ratio and the atomization cone angle. These shortcomings limit the further expansion of the combustion chamber ignition envelope, and there is still a need in the field for a technical solution that can achieve more stable adjustment, higher reliability, and take into account the coordinated optimization of multiple parameters. Summary of the Invention

[0008] This invention provides a flame tube head adjustment device to solve the technical problems in the prior art, such as the large air intake ratio of the vortex generator leading to drastic fluctuations in the oil-air ratio, the high-temperature failure of the elastic element resulting in poor reliability, and the inability to coordinate the adjustment of the atomization cone angle leading to limited ignition envelope widening.

[0009] According to one aspect of the present invention, a flame tube head adjustment device is provided, comprising a connecting cover plate, a venturi tube, a vortex generator, a fuel nozzle, and an elastic element. The connecting cover plate is connected to the end of the venturi tube facing the fuel nozzle and forms an adjustment cavity with the venturi tube. The vortex generator is sleeved outside the fuel nozzle, and the end of the vortex generator facing the venturi tube is movably disposed within the adjustment cavity. An air hole is provided on the wall of the fuel nozzle. The elastic element is disposed between the venturi tube and the vortex generator to apply an elastic force to the vortex generator to move it away from the venturi tube. When the engine is in a first operating state, the vortex generator moves away from the venturi tube under the action of the elastic force to block the air hole. When the engine is in a second operating state, the vortex generator moves towards the venturi tube under the action of the aerodynamic force to open the air hole.

[0010] As a further improvement to the above technical solution: Furthermore, the end of the venturi tube facing the fuel nozzle is recessed with a mounting groove, and the elastic element includes a spring piece arranged in the mounting groove and elastically abutting against the vortex generator. The length of the spring piece is greater than the outer length of the mounting groove and less than the inner length of the mounting groove.

[0011] Furthermore, multiple mounting grooves are recessed, and these multiple mounting grooves are arranged circumferentially at intervals on the end of the venturi tube facing the fuel nozzle, with the spring and mounting grooves arranged in a one-to-one correspondence.

[0012] Furthermore, the outer width of the mounting groove is greater than the width of the spring, and the depth of the mounting groove is greater than the thickness of the spring.

[0013] Furthermore, a hook is provided on the end of the spring that extends into the mounting groove.

[0014] Furthermore, the vortex generator includes an annular body fitted outside the fuel nozzle for blocking or opening the air hole, and an annular mounting edge movably arranged in the adjustment cavity, wherein the axial width of the adjustment cavity is greater than the axial width of the annular mounting edge.

[0015] Furthermore, the annular mounting edge includes a first sealing surface facing away from the venturi tube and a second sealing surface facing the venturi tube. The first sealing surface is used to fit and seal with the connecting cover plate in the first operating state of the engine, and the second sealing surface is used to fit and seal with the venturi tube in the second operating state of the engine.

[0016] Furthermore, the ring-shaped main body has inclined air inlets on its walls.

[0017] Furthermore, the fuel injector includes an injector head and an injector rod. The injector head is mounted on the injector rod and inserted into the vortex generator. A limiting part for limiting the vortex generator is protruding on the outer wall of the injector head, and an air hole is opened on the injector head.

[0018] According to another aspect of the invention, an aircraft engine is also provided, which includes the aforementioned flame tube head adjustment device.

[0019] The present invention has the following beneficial effects: The flame tube head adjustment device of the present invention connects to the end of the venturi tube facing the fuel nozzle via a connecting cover plate to form an adjustment cavity. A vortex generator is sleeved outside the fuel nozzle, and its end facing the venturi tube is movably positioned within the adjustment cavity. An air hole is provided in the wall of the fuel nozzle to allow external airflow to enter the fuel nozzle. An elastic element arranged between the venturi tube and the vortex generator applies an elastic force to the vortex generator, causing it to move away from the venturi tube. When the engine is in its first operating state, the vortex generator, under the action of the elastic force, overcomes the aerodynamic force and moves away from the venturi tube. The vortex generator moves in the direction of airflow to block the air orifice, preventing external airflow from entering the flame tube. This results in a relatively small intake volume at the flame tube head, a large air-fuel ratio, and a large atomization cone angle for the fuel nozzle due to the lack of external airflow. This leads to a larger main combustion zone within the flame tube, making it easier for atomized fuel to contact the spark plug in the main combustion zone, thus widening the ignition envelope and improving ignition performance. When the engine is in its second state, the vortex generator, under aerodynamic force, overcomes elastic force and moves towards the venturi tube to open the air orifice. External airflow then enters the flame tube through the air orifice, and the flame... The relatively large air intake at the nozzle head reduces the air-fuel ratio, which helps reduce pollutant emissions. Furthermore, due to the external airflow entering the nozzle, the atomization cone angle of the fuel nozzle decreases, consequently reducing the main combustion zone within the flame tube. This helps lower the inner wall temperature of the flame tube and improves its performance. In addition, compared to existing technologies, this design has a relatively smaller air intake proportion at the air orifice of the fuel nozzle, resulting in a smoother change in air intake at the flame tube head. This ensures stable combustion chamber operation during switching between operating states, thus stabilizing engine operation. Because the elastic element is positioned between the venturi tube and the swirl converter, away from the main combustion zone of the flame tube, it provides… It effectively avoids the problem of elastic components loosening or failing during long-term service in high-temperature environments, significantly improving the long-term reliability of the regulating device in harsh hot environments. The changing air volume comes from the air holes on the fuel nozzle, realizing the coordinated adjustment of the fuel-air ratio and atomization cone angle. This achieves coordinated matching of the air flow field and fuel space distribution across the entire operating range, ensuring reliable ignition and stable combustion under low-temperature conditions while also taking into account the requirements for low emissions and low wall temperatures under high-temperature conditions. It also effectively broadens the ignition and quenching envelope of the combustion chamber and improves combustion chamber performance. It is highly practical and suitable for widespread promotion and application.

[0020] In addition to the objectives, features, and advantages described above, the present invention has other objectives, features, and advantages. The invention will now be described in further detail with reference to the figures. Attached Figure Description

[0021] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings: Figure 1 This is a cross-sectional schematic diagram of the flame tube head adjustment device according to a preferred embodiment of the present invention; Figure 2 This is a cross-sectional schematic diagram of the flame tube head adjustment device of a preferred embodiment of the present invention in the first operating state of the engine; Figure 3 This is a cross-sectional schematic diagram of the flame tube head adjustment device of a preferred embodiment of the present invention in the second operating state of the engine; Figure 4 This is a schematic diagram of the structure of the Wen U-tube in the flame tube head adjustment device of a preferred embodiment of the present invention; Figure 5 This is a partial cross-sectional schematic diagram of the Venturi tube portion of the flame tube head adjustment device according to a preferred embodiment of the present invention; Figure 6 This is a cross-sectional schematic diagram of the mantle and spring sheet of the flame tube head adjustment device of the preferred embodiment of the present invention in the first working state of the engine. Figure 7 This is a cross-sectional schematic diagram of the mantle and spring sheet of the flame tube head adjustment device of the preferred embodiment of the present invention in the second working state of the engine; Figure 8 This is a cross-sectional schematic diagram of the connecting cover plate in the flame tube head adjustment device of a preferred embodiment of the present invention; Figure 9 This is a schematic diagram of the vortex generator in the flame tube head adjustment device of a preferred embodiment of the present invention; Figure 10 This is a schematic diagram of the spring sheet in the flame tube head adjustment device of a preferred embodiment of the present invention.

[0022] Legend: 10. Connecting cover plate; 20. Venturi tube; 21. Mounting groove; 30. Swirl generator; 31. Annular body; 311. First sealing surface; 312. Second sealing surface; 32. Annular mounting edge; 321. Air inlet; 40. Fuel nozzle; 41. Air hole; 42. Nozzle head; 43. Nozzle rod; 50. Elastic element; 51. Spring; 52. Hook. Detailed Implementation

[0023] The following description provides specific application scenarios and requirements for this specification, intended to enable those skilled in the art to make and use the contents of this specification. Various partial modifications to the disclosed embodiments will be apparent to those skilled in the art, and the general principles defined herein can be applied to other embodiments and applications without departing from the spirit and scope of this specification.

[0024] like Figure 1 , Figure 2 , Figure 3 and Figure 8 As shown, the flame tube head adjustment device of this embodiment includes a connecting cover plate 10, a venturi tube 20, a vortex generator 30, a fuel nozzle 40, and an elastic element 50. The connecting cover plate 10 is connected to the end of the venturi tube 20 facing the fuel nozzle 40 and forms an adjustment cavity with the venturi tube 20. The vortex generator 30 is sleeved outside the fuel nozzle 40, and the end of the vortex generator 30 facing the venturi tube 20 is movably disposed within the adjustment cavity. An air hole 41 is provided on the wall of the fuel nozzle 40. The elastic element 50 is arranged between the venturi tube 20 and the vortex generator 30 to apply an elastic force to the vortex generator 30 to move it away from the venturi tube 20. When the engine is in the first operating state, the vortex generator 30 moves away from the venturi tube 20 under the action of the elastic force to block the air hole 41. When the engine is in the second operating state, the vortex generator 30 moves towards the venturi tube 20 under the action of the aerodynamic force to open the air hole 41.

[0025] like Figure 1 , Figure 2 , Figure 3 and Figure 8As shown, specifically, the flame tube head adjustment device of the present invention is connected to the end of the venturi tube 20 facing the fuel nozzle 40 via a connecting cover plate 10 to form an adjustment cavity. The vortex generator 30 is sleeved outside the fuel nozzle 40, and its end facing the venturi tube 20 is movably positioned within the adjustment cavity. An air hole 41 is provided on the wall of the fuel nozzle 40 to allow external airflow to flow into the fuel nozzle 40. An elastic force is applied to the vortex generator 30 by an elastic member 50 arranged between the venturi tube 20 and the vortex generator 30, causing it to move away from the venturi tube 20. When the engine is in its first operating state, the vortex generator... Under the action of elastic force, the vortex injector 30 overcomes the aerodynamic force and moves away from the venturi tube 20 to block the air hole 41. The airflow outside the nozzle cannot enter the flame tube through the air hole 41, resulting in a relatively small intake volume at the flame tube head and a large air-fuel ratio. Furthermore, because the airflow outside the nozzle does not intervene, the atomization cone angle of the fuel injector 40 is large, and the main combustion zone within the flame tube is large. The atomized fuel easily contacts the spark of the ignition electrode in the main combustion zone, thereby widening the ignition envelope and improving ignition performance. When the engine is in its second operating state, the vortex injector 30 overcomes the elastic force under the action of aerodynamic force and moves towards the venturi tube 20 to open the air hole 41, and the nozzle... External airflow enters the flame tube through air hole 41. The air intake at the flame tube head is relatively large, reducing the air-fuel ratio and thus reducing pollutant emissions. Furthermore, due to the external airflow entering the nozzle, the atomization cone angle of the fuel nozzle 40 decreases, consequently reducing the main combustion zone within the flame tube. This helps lower the inner wall temperature of the flame tube and improves its performance. In addition, compared to existing technologies, this design has a relatively smaller air intake proportion through air hole 41 on the fuel nozzle 40, resulting in a smoother change in air intake at the flame tube head. This ensures stable combustion chamber operation during switching between operating states, thereby stabilizing engine operation. Since the elastic element 50 is positioned between the venturi tube 20 and the swirl generator 30... Located away from the main combustion zone of the flame tube, this effectively avoids the problem of loosening or failure of the elastic component 50 during long-term service in high-temperature environments. It significantly improves the long-term reliability of the regulating device under harsh thermal conditions. The varying air volume originates from the air hole 41 on the fuel nozzle 40, achieving coordinated adjustment of the air-fuel ratio and atomization cone angle. This ensures coordinated matching of the airflow field and fuel spatial distribution across the entire operating range, guaranteeing reliable ignition and stable combustion under low-temperature conditions while also meeting the requirements for low emissions and low wall temperatures under high-temperature conditions. It also effectively broadens the ignition and quenching envelope of the combustion chamber and improves combustion chamber performance, making it highly practical and suitable for widespread promotion and application. Optionally, the connecting cover plate 10 is welded and fixed to the end face of the venturi tube 20 facing the fuel nozzle 40.

[0026] In this embodiment, the first operating state of the engine is the engine idle speed or below, and the second operating state of the engine is the engine idle speed or above.

[0027] It should be understood that when the engine is in its first operating state, the aerodynamic force exerted by the engine on the vortex generator 30 is less than the elastic force exerted by the elastic element 50. Therefore, under the action of the elastic force, the vortex generator 30 overcomes the aerodynamic force and moves away from the venturi tube 20.

[0028] It should be understood that when the engine is in the second operating state, the aerodynamic force exerted by the engine on the vortex generator 30 is greater than the elastic force exerted by the elastic element 50. Therefore, under the action of aerodynamic force, the vortex generator 30 overcomes the elastic force and moves toward the direction closer to the venturi tube 20.

[0029] like Figures 4-7 As shown, in this embodiment, the venturi tube 20 has a recessed mounting groove 21 at its end facing the fuel nozzle 40. The elastic element 50 includes a spring piece 51 disposed within the mounting groove 21 and elastically abutting against the swirl converter 30. The length of the spring piece 51 is greater than the outer length of the mounting groove 21 and less than the inner length of the mounting groove 21. Specifically, the venturi tube 20 reliably mounts the spring piece 51 through the mounting groove 21. The elastic abutment between the spring piece 51 and the swirl converter 30 applies an elastic force to the swirl converter 30. The length of the spring piece 51, being greater than the outer length of the mounting groove 21 and less than the inner length of the mounting groove 21, prevents the spring piece 51 from falling out of the mounting groove 21. Optionally, the mounting groove 21 is a recessed groove.

[0030] like Figure 4 As shown, in this embodiment, multiple mounting slots 21 are recessed and arranged circumferentially at intervals on the end of the venturi tube 20 facing the fuel nozzle 40. The spring pieces 51 are arranged in a one-to-one correspondence with the mounting slots 21. Specifically, multiple spring pieces 51 are installed through the multiple mounting slots 21 to increase the elastic force applied to the vortex generator 30, ensuring that the vortex generator 30 can stably block the air hole 41 during the engine's first operating state.

[0031] It should be understood that the number of mounting slots 21 is set according to the air flow of the engine. The purpose is to ensure that the aerodynamic force applied to the vortex generator 30 in the first operating state of the engine is less than the elastic force applied to the vortex generator 30 by the elastic element 50, and to ensure that the aerodynamic force applied to the vortex generator 30 in the second operating state of the engine is greater than the elastic force applied to the vortex generator 30 by the elastic element 50.

[0032] like Figures 6-7 As shown, in this embodiment, the outer width of the mounting groove 21 is greater than the width of the spring piece 51, and the depth of the mounting groove 21 is greater than the thickness of the spring piece 51. This is to facilitate the installation of the spring piece 51 while ensuring smooth movement of the spring piece 51, avoiding interference between them and hindering the movement of the vortex generator 30. This enables adaptive adjustment of the airflow entering the flame tube head through the air hole 41 on the fuel nozzle 40 according to changes in the engine's operating state, thereby adaptively adjusting the atomization cone angle and the fuel-air ratio.

[0033] like Figure 10 As shown, in this embodiment, a hook 52 is provided on the end of the spring piece 51 that extends into the mounting groove 21. Specifically, after the spring piece 51 is installed into the mounting groove 21, the hook 52 forms an inverted buckle, which can prevent the spring piece 51 from coming out of the mounting groove 21. The hook 52 abuts against the side wall of the mounting groove 21 and can prevent the spring piece 51 from moving around in the mounting groove 21, ensuring that the spring piece 51 moves smoothly.

[0034] like Figure 9 As shown, in this embodiment, the vortex generator 30 includes an annular body 31 sleeved outside the fuel nozzle 40 for blocking or opening the air hole 41, and an annular mounting edge 32 movably arranged in the adjustment cavity, wherein the axial width of the adjustment cavity is greater than the axial width of the annular mounting edge 32. Specifically, the annular mounting edge 32 is axially and radially limited by the inner wall of the adjusting cavity. Furthermore, the axial width of the adjusting cavity is greater than the axial width of the annular mounting edge 32, allowing the annular mounting edge 32 to move axially within the adjusting cavity. This allows the annular body 31 to either block or open the air hole 41. Specifically, when the engine is in its first operating state, the elastic element 50 applies an elastic force to the annular mounting edge 32, causing the annular mounting edge 32 to move axially away from the venturi tube 20 within the adjusting cavity. This causes the annular body 31 to block the air hole 41 on the fuel nozzle 40, preventing external airflow from flowing into the fuel nozzle 40 through the air hole 41. When the engine is in its second operating state, the aerodynamic force on the vortex generator 30 is greater than the elastic force applied to the annular mounting edge 32 by the elastic element 50. The annular mounting edge 32 moves axially towards the venturi tube 20 within the adjusting cavity, causing the annular body 31 to open the air hole 41 on the fuel nozzle 40, allowing external airflow to flow into the fuel nozzle 40 through the air hole 41. Optionally, the annular body 31 and the annular mounting edge 32 are integrally formed.

[0035] like Figure 9 As shown, in this embodiment, the annular mounting edge 32 includes a first sealing surface 311 facing away from the venturi tube 20 and a second sealing surface 312 facing the venturi tube 20. The first sealing surface 311 is used to seal against the connecting cover plate 10 in the first operating state of the engine, and the second sealing surface 312 is used to seal against the venturi tube 20 in the second operating state of the engine. Specifically, when the engine is in the first operating state, the first sealing surface 311 is sealed against the connecting cover plate 10 to prevent external airflow from seeping into the flame tube from between the first sealing surface 311 and the connecting cover plate 10; when the engine is in the second operating state, the second sealing surface 312 is sealed against the venturi tube 20 to prevent airflow flowing into the regulating chamber from the gap between the vortex generator 30 and the connecting cover plate 10 from seeping into the flame tube from between the second sealing surface 312 and the venturi tube 20.

[0036] In this embodiment, the annular body 31 has inclined air inlets 321 on its wall. Specifically, the vortex generator 30 takes in air through the inclined air inlets 321. Compared with the axial air intake method, this can effectively shorten the axial length of the vortex generator 30, reduce the space occupied, and is suitable for small and medium-sized aero engines. Moreover, this structure is simple to manufacture and has low cost.

[0037] like Figures 1-3 As shown, in this embodiment, the fuel nozzle 40 includes a nozzle head 42 and a nozzle rod 43. The nozzle head 42 is mounted on the nozzle rod 43 and inserted into the vortex generator 30. A limiting portion for limiting the vortex generator 30 is protruding from the outer wall of the nozzle head 42. An air hole 41 is opened on the nozzle head 42. Specifically, the nozzle head 42 is reliably mounted by the nozzle rod 43 so that the nozzle head 42 is inserted into the vortex generator 30. The nozzle head 42 axially limits the vortex generator 30 through the limiting portion, so that when the vortex generator 30 moves away from the venturi tube 20, the limiting portion abuts against the vortex generator 30, thereby achieving precise positioning of the axial position of the vortex generator 30. Optionally, the air hole 41 is inclined radially from the outside to the inside towards the venturi tube 20 to guide the movement of the airflow.

[0038] The aero-engine of this embodiment includes the aforementioned flame tube head adjustment device. Specifically, by using the aforementioned flame tube head adjustment device in the aero-engine, the ignition envelope is widened and ignition performance is improved when the aero-engine is in the first operating state; pollutant emissions are reduced when the aero-engine is in the second operating state; and the stable operation of the combustion chamber is ensured throughout the entire process, thus ensuring the stable operation of the aero-engine.

[0039] In summary, after reading the detailed disclosure of this specification, those skilled in the art will understand that the foregoing detailed disclosure is presented by way of example only and is not restrictive. Although not explicitly stated herein, those skilled in the art will understand that this specification requires various reasonable changes, improvements, and modifications to the embodiments. These changes, improvements, and modifications are intended to be made by this specification and are within the spirit and scope of the exemplary embodiments described herein.

Claims

1. A flame tube head adjustment device, characterized by, The device includes a connecting cover plate (10), a venturi tube (20), a vortex generator (30), a fuel nozzle (40), and an elastic element (50). The connecting cover plate (10) is connected to the end of the venturi tube (20) facing the fuel nozzle (40) and forms an adjustment cavity with the venturi tube (20). The vortex generator (30) is sleeved outside the fuel nozzle (40). The end of the vortex generator (30) facing the venturi tube (20) is movably disposed in the adjustment cavity. An air hole (41) is provided on the wall of the fuel nozzle (40). The elastic element (50) is arranged between the venturi tube (20) and the vortex generator (30) to apply an elastic force to the vortex generator (30) to move away from the venturi tube (20). When the engine is in its first operating state, the vortex generator (30) moves away from the venturi tube (20) in the direction of overcoming aerodynamic force under the action of elastic force, so as to block the air hole (41). When the engine is in the second operating state, the vortex generator (30) moves towards the Venturi tube (20) under the action of aerodynamic force, overcoming the elastic force, to open the air hole (41).

2. The flame tube head adjusting device according to claim 1, characterized in that, The Venturi tube (20) has a recessed mounting groove (21) at the end facing the fuel nozzle (40). The elastic element (50) includes a spring piece (51) arranged in the mounting groove (21) and elastically abutting against the vortex generator (30). The length of the spring piece (51) is greater than the outer length of the mounting groove (21) and less than the inner length of the mounting groove (21).

3. The flame tube head adjusting device according to claim 2, characterized in that, The mounting groove (21) is recessed in multiple places. The multiple mounting grooves (21) are arranged circumferentially at intervals on the end of the venturi tube (20) facing the fuel nozzle (40). The spring piece (51) and the mounting groove (21) are arranged in a one-to-one correspondence.

4. The flame tube head adjusting device according to claim 2, characterized in that, The outer width of the mounting groove (21) is greater than the width of the spring (51), and the depth of the mounting groove (21) is greater than the thickness of the spring (51).

5. The flame tube head adjusting device according to claim 2, characterized in that, The end of the spring clip (51) that extends into the mounting groove (21) is provided with a hook (52).

6. The flame tube head adjusting device according to any one of claims 1-5, characterized in that, The vortex generator (30) includes an annular body (31) fitted outside the fuel nozzle (40) for blocking or opening the air hole (41), and an annular mounting edge (32) movably arranged in the adjustment cavity, the axial width of the adjustment cavity being greater than the axial width of the annular mounting edge (32).

7. The flame tube head adjusting device according to claim 6, characterized in that, The annular mounting edge (32) includes a first sealing surface (311) facing away from the venturi tube (20) and a second sealing surface (312) facing the venturi tube (20). The first sealing surface (311) is used to fit and seal with the connecting cover plate (10) in the first operating state of the engine, and the second sealing surface (312) is used to fit and seal with the venturi tube (20) in the second operating state of the engine.

8. The flame tube head adjusting device according to claim 6, characterized in that, The ring-shaped main body (31) has inclined air inlets (321) on its wall.

9. The flame tube head adjusting device according to any one of claims 1-5, characterized in that, The fuel injector (40) includes an injector head (42) and an injector rod (43). The injector head (42) is mounted on the injector rod (43) and inserted into the vortex generator (30). A limiting part for limiting the vortex generator (30) is protruding on the outer wall of the injector head (42). An air hole (41) is opened on the injector head (42).

10. An aircraft engine, characterized in that, The flame tube head adjustment device includes any one of claims 1-9.

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