Variable circulation afterburner with outer culvert matched with oil supply and injection switching

Abstract

The variable-circulation afterburner comprises a flow dividing ring and a flow blocking ring, the inner wall of the flow dividing ring protrudes towards the radial outer side to form an annular concave cavity, a radial injection opening is formed in the peripheral wall of the flow dividing ring, an axial injection opening is formed in the front wall of the concave cavity, and the radial injection opening is communicated with the axial injection opening. The multiple radial injection openings and the multiple axial injection openings are formed in the circumferential direction, and the radial injection openings and the axial injection openings are alternately formed or aligned in the circumferential direction. The flow blocking ring comprises a plurality of flow blocking ring radial windows and a plurality of flow blocking ring axial windows, the flow blocking ring can rotate in the circumferential direction relative to the flow dividing ring, the flow blocking ring can be switched between a flow blocking ring first state and a flow blocking ring second state, in the flow blocking ring first state, the flow blocking ring radial windows and the radial injection openings at least partially coincide, and in the flow blocking ring second state, the flow blocking ring radial windows and the flow blocking ring axial windows at least partially coincide. In the first state of the flow blocking ring, the axial injection opening is blocked by the flow blocking ring, in the second state of the flow blocking ring, the axial window of the flow blocking ring and the axial injection opening are at least partially overlapped, and the radial injection opening is blocked by the flow blocking ring.

Description

Technical Field

[0001] The present application belongs to the field of aviation engine technology, and particularly relates to a variable cycle afterburner combustion chamber with external matching fuel supply and injection switching. Background Art

[0002] Variable cycle engines have the advantages of low fuel consumption of large bypass ratio turbofan engines at subsonic speeds and high thrust of small bypass ratio engines at supersonic speeds. They are one of the main development directions of future aviation engines.

[0003] Variable-cycle engines achieve thermodynamic cycles with varying characteristics by adjusting the geometry, size, or position of certain components to alter engine cycle parameters. Mode switching enables operation across a wide range of bypass ratios, greatly enhancing the engine's adaptability to complex and changing missions. However, this also presents significant challenges for engine design.

[0004] The wide bypass ratio (e.g. 0.2 to 1.0) operating characteristics of variable cycle engines pose a challenge to the design of afterburner combustion chambers. The afterburner combustion chamber of a variable cycle engine needs to achieve efficient combustion under wide bypass ratio conditions, especially to ensure combustion efficiency under large bypass ratio conditions. In addition, the afterburner combustion chamber must also take into account the total pressure recovery coefficient in the non-afterburner state. Under large bypass ratio conditions, efficient combustion organization of oxygen-rich air injected into the outer envelope is the key to improving afterburner combustion efficiency. However, the stability of the flame and the strong mixing of the inner and outer envelope airflows will lead to an increase in the total pressure loss in the non-afterburner state. How to balance the combustion organization in the afterburner state and the total pressure loss in the non-afterburner state is the key to the design of the afterburner combustion chamber of a variable cycle engine. Summary of the Invention

[0005] The present application aims to propose a variable cycle afterburner combustion chamber with external matching fuel supply and ejection switching, which can balance the total pressure recovery coefficient in the non-afterburner state and the combustion efficiency in the afterburner state.

[0006] The embodiment of the present application proposes a variable cycle afterburner with external matching fuel supply and injection switching, including a diverter ring and a baffle ring.

[0007] The diverter ring is cylindrical and separates the inner flow channel and the outer flow channel. The inner wall of the diverter ring bulges radially outward to form an annular concave cavity. The concave cavity is located at the downstream end of the diverter ring. The circumferential wall of the diverter ring located at the upstream part of the concave cavity is provided with a radial injection port, and the front wall of the concave cavity is provided with an axial injection port. A plurality of radial injection ports and axial injection ports are provided along the circumferential direction, and the radial injection ports and the axial injection ports are alternately arranged or aligned along the circumferential direction.

[0008] The flow blocking ring is sleeved on the radial outer side of the flow dividing ring, the flow blocking ring comprises a plurality of flow blocking ring radial windows and a plurality of flow blocking ring axial windows, the flow blocking ring is capable of rotating relative to the flow dividing ring along the circumferential direction, the flow blocking ring is capable of switching between a flow blocking ring first state and a flow blocking ring second state, wherein,

[0009] In the flow blocking ring first state, the flow blocking ring radial windows and the radial injection ports at least partially coincide, the axial injection ports are shielded by the flow blocking ring,

[0010] In the flow blocking ring second state, the flow blocking ring axial windows and the axial injection ports at least partially coincide, the radial injection ports are shielded by the flow blocking ring.

[0011] In at least one possible technical solution, the recessed cavity comprises a recessed cavity front wall, a recessed cavity peripheral wall and a recessed cavity rear wall, the recessed cavity peripheral wall extends along the axial direction and the circumferential direction, the recessed cavity front wall is connected to the upstream end of the recessed cavity peripheral wall, the recessed cavity front wall extends along the radial direction and the circumferential direction, the recessed cavity front wall and the recessed cavity peripheral wall are perpendicular to each other, the recessed cavity rear wall is connected to the downstream end of the recessed cavity peripheral wall, the recessed cavity rear wall is inclined relative to the axial direction, the more the recessed cavity rear wall extends to the downstream side, the more it is inclined to the radial inner side.

[0012] In at least one possible technical solution, the flow blocking ring comprises an axial extension and a radial extension, the axial extension extends along the axial direction and the circumferential direction, the flow blocking ring radial windows are arranged on the axial extension, the radial extension extends along the radial direction and the circumferential direction, the flow blocking ring axial windows are arranged on the radial extension,

[0013] In the circumferential direction, the radial injection ports and the axial injection ports are arranged alternately along the circumferential direction, the flow blocking ring radial windows and the flow blocking ring axial windows are located in the same region;

[0014] Alternatively, in the circumferential direction, the radial injection ports and the axial injection ports are arranged in alignment along the circumferential direction, the flow blocking ring radial windows and the flow blocking ring axial windows are arranged alternately.

[0015] In at least one possible technical solution, the coinciding part of the flow blocking ring radial windows and the radial injection ports can be adjusted between 0% and 100% while keeping the axial injection ports shielded by the flow blocking ring,

[0016] The coinciding part of the flow blocking ring axial windows and the axial injection ports can be adjusted between 0% and 100% while keeping the radial injection ports shielded by the flow blocking ring.

[0017] In at least one possible technical solution, the radial injection port and the axial injection port are spaced apart in the circumferential direction.

[0018] In at least one possible technical solution, the afterburner further comprises a plurality of struts arranged along the circumferential direction in the inner bypass flow channel,

[0019] The radial injection port and the strut are staggered in the circumferential direction, and the axial injection port and the strut are located in the same circumferential region.

[0020] In at least one possible technical solution, in the circumferential direction, the lengths of the radial injection port, the axial injection port, the shroud ring radial window, and the shroud ring axial window are the same, and their circumferential lengths are one third of the staggered angle of the adjacent two struts.

[0021] In at least one possible technical solution, the inside of the strut is provided with an oil injection rod, and the oil injection rod is connected with a plurality of oil injection nozzles arranged to be able to inject oil in a direction perpendicular to the strut.

[0022] In at least one possible technical solution, the afterburner further comprises an adjustable ejector,

[0023] The adjustable ejector is arranged on the downstream side of the splitter ring, and the adjustable ejector is axially movable relative to the splitter ring,

[0024] An adjustable bypass injection passage is formed between the adjustable ejector and the cavity rear wall, and the opening of the adjustable bypass injection passage can be adjusted by the axial movement of the adjustable ejector.

[0025] In at least one possible technical solution, the included angle of the cavity rear wall relative to the axial direction is 20 to 40 degrees.

[0026] By adopting the above technical solution, by adjusting the state of the shroud ring, the air in the bypass flow channel can pass through different passages into the inner bypass flow channel in the non-afterburning state and the afterburning state, thereby balancing the total pressure recovery coefficient in the non-afterburning state and the combustion efficiency in the afterburning state. BRIEF DESCRIPTION OF DRAWINGS

[0027] Figure 1 A partial structure schematic diagram of a variable cycle afterburner with bypass matching oil supply and injection switching according to an embodiment of the present application is shown.

[0028] Figure 2 A partial enlarged view of a variable cycle afterburner with bypass matching oil supply and injection switching according to an embodiment of the present application in an afterburning state is shown.

[0029] Figure 3 A partial enlarged view of a variable cycle afterburner with outer bypass matching fuel supply and ejector switching in a non-afterburning state is shown.

[0030] Figure 4 A partial structural schematic view of a variable cycle afterburner with outer bypass matching fuel supply and ejector switching is shown.

[0031] BRIEF DESCRIPTION OF DRAWINGS

[0032] 1 Casing

[0033] 2 Strut 21 Fuel injection rod

[0034] 3 Center cone

[0035] 4 Splitter ring 41 Radial ejector port 42 Axial ejector port 43 Fuel supply nozzle

[0036] 5 Baffle ring 51 Axial extension 52 Radial extension 53 Baffle ring radial window 54 Baffle ring axial window

[0037] 6 Fuel injection ring

[0038] 7 Adjustable ejector

[0039] 8 Heat shield

[0040] S Cavity S1 Cavity front wall S2 Cavity peripheral wall S3 Cavity back wall

[0041] L1 Inner bypass flow passage L2 Outer bypass flow passage

[0042] I1 Outer bypass radial ejector passage I2 Outer bypass axial ejector passage I3 Adjustable outer bypass ejector passage

[0043] A Axial R Radial DETAILED DESCRIPTION

[0044] In order to more clearly illustrate the above-mentioned purposes, features and advantages of the present application, the specific embodiments of the present application are described in detail in this section in conjunction with the drawings. In addition to the various embodiments described in this section, the present application can be implemented in other different ways, and those skilled in the art can make corresponding improvements, modifications and substitutions without departing from the spirit of the present application, so the present application is not limited to the specific embodiments disclosed in this section. The scope of protection of the present application should be subject to the claims.

[0045] As shown in Figures 1 to 4 the embodiments of the present application propose a variable cycle afterburner with outer bypass matching fuel supply and ejector switching, which comprises a casing 1, a strut 2, a center cone 3, a splitter ring 4, a baffle ring 5, a fuel injection ring 6, an adjustable ejector 7 and a heat shield 8.

[0046] The casing 1, center cone 3, diverter ring 4, baffle ring 5, adjustable ejector 7 and heat shield 8 are all coaxially arranged. The casing 1 and diverter ring 4 are cylindrical. The diverter ring 4 is located radially inside the casing 1, and the center cone 3 is located radially inside the diverter ring 4. The space between the diverter ring 4 and the center cone 3 is the inner flow channel L1, and the space between the casing 1 and the diverter ring 4 is the outer flow channel L2. The diverter ring 4 separates the inner flow channel L1 and the outer flow channel L2. In the direction of the upstream to downstream direction of the airflow ( Figure 1 In the direction from left to right in the center, the outer peripheral surface of the central cone 3 is gradually contracting, so that the inner flow channel L1 is a gradually expanding channel, which is conducive to decelerating and pressurizing the airflow passing through the inner flow channel L1.

[0047] Multiple support plates 2 are evenly arranged along the circumferential direction C of the afterburner, radially arranged within the internal flow channel L1. Each support plate 2 may be internally provided with one or more fuel injection rods 21, each of which may be connected to multiple fuel injection nozzles. The fuel injection nozzles may be located on either side of the support plate 2 and configured to inject fuel perpendicularly to the support plate 2. The integration of the fuel injection rods 21 into the support plate 2 enables the support plate 2 to function as a fuel supply, flow regulator, and flame stabilizer.

[0048] In this embodiment, there may be 12 support plates 2. Optionally, the extension direction of the oil spray rod 21 may be parallel to the trailing edge of the support plate 2; and the oil spray nozzle may be circular.

[0049] like Figures 1 to 3 As shown, the inner wall of the diverter ring 4 bulges radially outward to form an annular concave cavity S, which can be located at the tail end (downstream end) of the diverter ring 4. Figure 1 The right end in FIG), the cross section (axial cross section) of the cavity S may be a trapezoid.

[0050] The cavity S may include a cavity front wall S1, a cavity outer wall S2, and a cavity rear wall S3. The cavity outer wall S2 may extend in the axial direction A and the circumferential direction C. The cavity front wall S1 is connected to the upstream end of the cavity outer wall S2. The cavity front wall S1 may extend in the radial direction R and the circumferential direction C. The cavity front wall S1 and the cavity outer wall S2 may be perpendicular to each other. The cavity rear wall S3 is connected to the downstream end of the cavity outer wall S2. The cavity rear wall S3 may be inclined relative to the axial direction A, and the cavity rear wall S3 may be inclined radially inward as it extends downstream. The cavity S can stabilize the flame of the outer flow passage L2 and enable circumferential flame connection in the afterburner.

[0051] Optionally, the angle θ of the cavity rear wall S3 relative to the axial direction A may be 20 to 40 degrees, for example, the angle θ may be 30 degrees.

[0052] The circumferential wall of the diverter ring 4 located upstream of the cavity S can be provided with a radial injection port 41, and the front wall S1 of the cavity can be provided with an axial injection port 42. Multiple radial injection ports 41 and axial injection ports 42 are provided along the circumferential direction C. The radial injection ports 41 and the axial injection ports 42 are alternately arranged along the circumferential direction C and are completely staggered in the circumferential direction C, not occupying the same circumferential area. The gas in the outer duct L2 can flow along the radial direction R into the inner duct L1 through the radial injection port 41. The gas in the outer duct L2 can flow along the axial direction A into the cavity S through the axial injection port 42.

[0053] Furthermore, the radial injection port 41 and the support plate 2 may be staggered in the circumferential direction C to prevent the injection airflow through the radial injection port 41 from affecting the flame stabilization effect of the support plate 2. The axial injection port 42 and the support plate 2 may be located in the same circumferential region.

[0054] The oil injection ring 6 may be arranged radially outside the diverter ring 4 . The oil injection ring 6 may have a plurality of oil injection nozzles extending into the concave cavity S, so as to be able to inject oil into the concave cavity S for combustion.

[0055] like Figures 1 to 3 As shown, the baffle ring 5 can be sleeved radially outside the diverter ring 4. The baffle ring 5 can include an axial extension 51 and a radial extension 52. The axial extension 51 can extend in the axial direction A and the circumferential direction C, while the radial extension 52 can extend in the radial direction R and the circumferential direction C. The axial extension 51 can be connected to the inner circumference of the radial extension 52. The axial extension 51 can be tightly fitted to the circumferential wall of the diverter ring 4 located upstream of the concave cavity S, while the radial extension 52 can be tightly fitted to the front wall S1 of the concave cavity. The axial extension 51 can be provided with a plurality of baffle ring radial windows 53, while the radial extension 52 can be provided with a plurality of baffle ring axial windows 54. In the circumferential direction C, the baffle ring radial windows 53 and the baffle ring axial windows 54 can be located in the same area.

[0056] Optionally, the radial window 53 of the baffle ring and the axial window 54 of the baffle ring may be rectangular, oblong, or fan-shaped.

[0057] The shift ring 5 can be driven by, for example, a rotational actuator to rotate relative to the diverter ring 4 along the circumferential direction C, so that the shift ring 5 can be switched between a first shift ring state and a second shift ring state.

[0058] like Figure 2 As shown, in the first state of the baffle ring (forced state), the radial window 53 of the baffle ring and the radial injection port 41 at least partially overlap to form an outer radial injection channel I1. The gas in the outer flow channel L2 can flow along the radial direction R into the inner flow channel L1 through the outer radial injection channel I1, and the axial window 54 of the baffle ring is blocked by the baffle ring 5.

[0059] like Figure 3As shown, in the second state of the blocker ring (non-reinforced state), the axial window 54 of the blocker ring and the axial injection port 42 at least partially coincide to form an outer-duct axial injection channel I2, through which the gas in the outer-duct flow passage L2 can flow in the axial direction A into the cavity S of the inner-duct flow passage L1, and the radial injection port 41 is blocked by the blocker ring 5.

[0060] The inclined cavity rear wall S3 can inhibit the aerodynamic separation of the mixed gas flow in the outer-duct axial injection channel I2 and the inner-duct flow passage L1, so that the gas flow adheres to the wall and stably enters downstream, reduces the total pressure loss, and improves the mixing efficiency.

[0061] Further, in the circumferential direction C, the radial injection port 41, the axial injection port 42, the blocker ring radial window 53, and the blocker ring axial window 54 have the same length, and the circumferential length of each of them is one third or less, for example, one fourth, one fifth, one sixth, etc., of the angle by which the adjacent two support plates 2 are offset. Here, the angle by which the adjacent two support plates 2 are offset refers to the angle by which the center positions of the adjacent two support plates 2 in the circumferential direction C are offset. It can be understood that when the circumferential length of the radial injection port 41, the axial injection port 42, the blocker ring radial window 53, and the blocker ring axial window 54 is one third of the angle by which the adjacent two support plates 2 are offset, the flow area of the outer-duct radial injection channel I1 can be adjusted in the range of 0% to 100% while keeping the outer-duct axial injection channel I2 closed, and the flow area of the outer-duct axial injection channel I2 can be adjusted in the range of 0% to 100% while keeping the outer-duct radial injection channel I1 closed, and the flow areas of the outer-duct radial injection channel I1 and the outer-duct axial injection channel I2 are larger.

[0062] In the circumferential direction C, the radial injection port 41 and the axial injection port 42 have a spacing. It can be understood that here having a spacing means that the radial injection port 41 and the axial injection port 42 have no overlapping part, and there is a spacing between the edges of the radial injection port 41 and the axial injection port 42 that are close to each other. When the radial injection port 41 and the axial injection port 42 are projected on the same surface in the axial direction A, they are still spaced apart from each other.

[0063] The circumferential angle by which the radial injection port 41, the axial injection port 42, and the radial injection port 41 and the axial injection port 42 are spaced apart can be the same.

[0064] For example, the adjacent two support plates 2 are offset by 30 degrees, and the circumferential angles of the radial injection port 41, the axial injection port 42, the blocker ring radial window 53, and the blocker ring axial window 54 are 10 degrees. The circumferential angle by which the radial injection port 41 and the axial injection port 42 are spaced apart is also 10 degrees.

[0065] By rotating the baffle ring 5, the opening and closing as well as the opening degree of the outer lining radial injection channel I1 and the outer lining axial injection channel I2 can be adjusted.

[0066] While the axial injection port 42 remains blocked by the baffle ring 5, the overlap between the baffle ring radial window 53 and the radial injection port 41 can be adjusted between 0% and 100%. This means that while the outer duct axial injection channel I2 remains closed, the flow area of ​​the outer duct radial injection channel I1 can be adjusted between 0% and 100%.

[0067] While the radial injection port 41 remains blocked by the baffle ring 5, the overlap between the baffle ring axial window 54 and the axial injection port 42 can be adjusted between 0% and 100%. That is, while the outer duct radial injection channel I1 remains closed, the flow area of ​​the outer duct axial injection channel I2 can be adjusted between 0% and 100%.

[0068] The adjustable ejector 7 can be arranged on the downstream side of the diverter ring 4. Specifically, the adjustable ejector 7 can be located radially outside the downstream end (terminal end) of the concave cavity rear wall S3 and located on the downstream side ( Figure 1 (right side in the figure), thereby forming an adjustable outer ejector channel I3 between the adjustable ejector 7 and the diverter ring 4. The adjustable ejector 7 can be driven by, for example, an axial actuator to move in the axial direction A relative to the diverter ring 4, thereby adjusting the opening of the adjustable outer ejector channel I3 and, therefore, the flow rate.

[0069] Optionally, the front wall of the adjustable ejector 7 may be parallel to the rear wall S3 of the cavity.

[0070] The heat shield 8 may be disposed on the downstream side of the adjustable ejector 7 . The heat shield 8 may be cylindrical and sleeved on the radially outer side of the adjustable ejector 7 .

[0071] The airflow injection direction of the outer radial injection channel I1 is perpendicular to the airflow direction (axial direction) of the inner flow channel L1, so the mixing effect of the inner and outer gases is better but the total pressure loss is larger.

[0072] The airflow direction of the outer axial injection channel I2 is parallel to the airflow direction of the inner flow channel L1, so the total pressure loss is small. The cavity S can achieve good mixing of the inner and outer gases, but it is not conducive to the cavity S to achieve the flame stabilization and flame connection functions.

[0073] The airflow injection direction of the adjustable outer injection channel I3 and the airflow direction of the inner flow channel L1 form an acute angle, and the total mixing pressure loss is small, but the mixing effect is moderate.

[0074] The outer matching oil supply and ejector switching variable cycle afterburner of the present application can comprehensively utilize the characteristic differences of different outer matching ejector channels, and match different ejector channels in different engine working modes to optimize the balance between combustion efficiency and cold state total pressure loss.

[0075] Referring to Figure 2 When the adaptive variable cycle engine is opened in the afterburning state, the rotating actuator adjusts the flow blocking ring 5, the flow blocking ring 5 blocks the axial ejector port 42 (i.e. closes the outer matching axial ejector channel I2), and the radial window 53 of the flow blocking ring and the radial ejector port 41 at least partially overlap (i.e. open the outer matching radial ejector channel I1). The axial position of the adjustable ejector 7 is adjusted to open the adjustable outer matching ejector channel I3. The air in the outer matching flow passage L2 enters the combustion chamber for combustion from the outer matching radial ejector channel I1 and the adjustable outer matching ejector channel I3.

[0076] The flow area of the outer matching radial ejector channel I1 can be adjusted by rotating the flow blocking ring 5 to match the amount of bleed air in the outer matching flow passage L2 at different bypass ratios (the ratio of the air flow in the outer matching flow passage L2 to the air flow in the inner matching flow passage L1).

[0077] In the afterburning state, the air in the outer matching flow passage L2 can enter the combustion chamber from the outer matching radial ejector channel I1 and the adjustable outer matching ejector channel I3, and the oil injection rod 21 and the oil injection ring 6 inject oil for combustion. The fuel flow injected by the oil injection rod 21 matches the variation of the air flow in the inner matching flow passage L1, forming a stable flame at the trailing edge of the strut 2. The oil injection ring 6 injects fuel into the cavity S and mixes with the bleed air in the outer matching flow passage L2 for combustion, and the fuel flow injected by the oil injection ring 6 matches the bleed air flow in the outer matching flow passage L2. The air in the outer matching flow passage L2 enters the inner matching flow passage L1 from the outer matching radial ejector channel I1, and fully mixes with the oil and gas in the cavity S, and is ignited by the high-temperature inner matching combustion gas. Through the cavity S, a low-speed zone can be constructed in the high-speed main flow in the inner matching flow passage L1, so that the fuel spray has a longer residence time in the cavity S, achieving good evaporation. The axial ejector port 42 of the cavity front wall S1 is blocked, so that the cavity S maintains an intact structure, and the flame can be well retained in the low-speed zone of the cavity S, the mixture of low-temperature outer matching air and fuel can be stably ignited, a stable ignition source is formed in the cavity S, and the circumferential flame of the afterburner is connected, so that the air in the outer matching flow passage L2 is fully and efficiently combusted, achieving good combustion efficiency.

[0078] The outer matching air entering the inner matching flow passage L1 from the adjustable outer matching ejector channel I3 can not only participate in combustion, but also to some extent isolate the contact between the outer matching combustion flame and the heat shield 8, reducing the cooling load of the heat shield 8.

[0079] Under the same bypass ratio (the ratio of the air flow of the outer bypass flow passage L2 to the inner bypass flow passage L1), by adjusting the flow distribution of the outer bypass radial injection channel I1 and the adjustable outer bypass injection channel I3, the dynamic adjustment of the combustion efficiency and the cooling load can be realized to match the needs of different engine operating states.

[0080] Especially in the large bypass ratio operating condition with relatively low combustion efficiency, the overall combustion efficiency of the afterburner can be improved by increasing the air flow proportion of the outer bypass radial injection channel I1. In the operating condition with high heat load of the heat shield 8, the air flow proportion of the adjustable outer bypass injection channel I3 can be appropriately increased to reduce the heat protection pressure of the heat shield 8.

[0081] Referring to Figure 3 When the adaptive variable cycle engine is in a non-afterburning state, the flow ring 5 is adjusted to block the radial injection port 41 (i.e., the outer bypass radial injection channel I1 is closed), and the axial window 54 of the flow ring and the axial injection port 42 at least partially overlap (i.e., the outer bypass axial injection channel I2 is opened). The axial position of the adjustable ejector 7 is adjusted to open the adjustable outer bypass injection channel I3. The injection air flow through the outer bypass axial injection channel I2 is parallel to the air flow direction of the inner bypass flow passage L1, thereby reducing the total pressure loss. The concave cavity S can achieve good mixing of the inner and outer bypass air, but is not conducive to the functions of the concave cavity S to achieve stable flame and combined flame.

[0082] The outer bypass air and the inner bypass air entering the concave cavity S from the outer bypass axial injection channel I2 can achieve good mixing and flow into the inner bypass flow passage L1 along the inclined concave cavity rear wall S3. The air entering the inner bypass flow passage L1 through the adjustable outer bypass injection channel has a small mixing total pressure loss due to the acute angle formed with the inner bypass flow passage L1.

[0083] Under the same bypass ratio (the ratio of the air flow of the outer bypass flow passage L2 to the inner bypass flow passage L1), by increasing the air flow of the outer bypass axial injection channel I2 and / or reducing the air flow of the adjustable outer bypass injection channel I3, the air mixing effect of the inner bypass flow passage L1 and the outer bypass flow passage L2 can be improved. Conversely, by reducing the air flow of the outer bypass axial injection channel I2 and / or increasing the air flow of the adjustable outer bypass injection channel I3, the total pressure recovery coefficient can be improved. Therefore, the inner and outer bypass mixing effect and the total pressure recovery coefficient can be flexibly matched and adjusted according to the operating state of the adaptive variable cycle engine.

[0084] In the non-afterburning state, when the engine operating state requires good inner and outer bypass mixing performance, the air flow proportion of the outer bypass axial injection channel I2 can be appropriately increased. When the engine operating state requires a higher total pressure recovery coefficient, the air flow proportion of the adjustable outer bypass injection channel I3 can be appropriately increased.

[0085] Referring to Figure 1 andFigure 4 In the embodiments of the present disclosure, by dividing the afterburner into the inner-duct L1 and the outer-duct L2, the inner-duct L1 includes oil supply regions separated by the plurality of struts 2. The adjustable ejector 7 is provided with a corresponding oil supply nozzle 43, and the included angle between the oil injection direction of the oil supply nozzle 43 and the air flow direction at the inlet of the adjustable ejector 7 satisfies greater than or equal to 0° and less than or equal to 180°. The real-time opening of the outer-duct injection channel (including the outer-duct radial injection channel I1, the outer-duct axial injection channel I2, and the adjustable outer-duct injection channel I3) is adjusted to regulate the flow of air from the outer-duct L2 into the inner-duct L1.

[0086] The oil supply regions separated by the struts 2 are obtained by dividing the inner-duct L1, and the outer-duct L2 and the oil supply paths of each strut partition can be designed to facilitate subsequent separate oil supply to the outer-duct L2 by the corresponding oil supply nozzle 43 of the adjustable ejector 7 and planning of the strut partitions of the inner-duct L1, thereby comprehensively improving the matching accuracy of fuel-oxygen and the effect of fuel-oxygen mixing, and further improving the overall combustion efficiency of the afterburner.

[0087] According to the real-time duct ratio of the afterburner, the corresponding oil supply mode of the afterburner can be determined to indicate whether to supply oil to the outer-duct L2 by the corresponding oil supply nozzle 43 of the adjustable ejector 7, realize the real-time adjustment and change of the oil supply scheme to the adjustable ejector 7, make the afterburner flexibly adjust the oil supply mode according to the change of the duct ratio, and improve the adaptability of the afterburner to different duct ratio working conditions and transition states in a wide duct ratio range. By respectively determining the real-time oxygen flow of each oil supply region and combining the oil supply mode, the target oil supply amount of each oil supply region can be determined, the fuel-oxygen matching of each oil supply region is realized, the accuracy of the target oil supply amount of each oil supply region is improved, the possibility of insufficient fuel combustion is reduced while the oxygen in each oil supply region is fully utilized, and fuel waste is avoided; according to the target oil supply amount of each oil supply region, the target oil path control scheme of each oil supply region is determined to accurately control the oil injection amount of each oil supply region, so that the fuel and oxygen can be fully mixed and combusted, the overall combustion efficiency of the afterburner under the large-duct ratio working condition and the transition state is improved, and the outlet temperature of the afterburner is improved, thereby realizing the effect of increasing the thrust of the aero-engine.

[0088] In summary, the variable cycle afterburner with outer-duct matching oil supply and injection switching of the present application can obtain the following beneficial effects.

[0089] (1) By setting the three ejection channels of the outer-duct radial ejection channel I1, the outer-duct axial ejection channel I2 and the adjustable outer-duct ejection channel I3, and adjusting the air flow of the three ejection channels under different working conditions, the working state requirements of the variable cycle engine are efficiently matched, the performance of the total pressure loss, the inner-outer-duct mixing, the combustion efficiency and the heat shield heat load is flexibly adjusted, and the balance of the total pressure recovery coefficient in the non-afterburning state and the combustion efficiency in the afterburning state is realized.

[0090] (2) By having the combustion organization structure with the cavity S, stable flame and circumferential flame are realized, the outer-duct ejection air can be efficiently combusted, and the combustion efficiency of the afterburner is improved.

[0091] (3) The air in the outer-duct flow passage L2 can enter the afterburner from the outer-duct radial ejection channel I1 and the adjustable outer-duct ejection channel I3, respectively, realizing the staged combustion of the inner-outer-duct air flow, and efficiently combusting in the afterburner of the variable cycle engine under a wide range of working duct ratios.

[0092] (4) According to the target fuel supply amount corresponding to each fuel supply area, the target oil path control scheme corresponding to each fuel supply area is determined to accurately control the fuel injection amount of each fuel supply area, so that the fuel and oxygen can be fully mixed and combusted, the overall combustion efficiency of the afterburner under the large-duct-ratio working condition and the transition state is improved, and the outlet temperature of the afterburner is improved, thereby realizing the effect of increasing the thrust of the aero-engine.

[0093] The present application is not limited to the above-mentioned embodiments, and those skilled in the art can make various modifications to the above-mentioned embodiments of the present application under the teaching of the present application without departing from the scope of the present application. In addition, the following is described.

[0094] In the above-described embodiment, the radial ejection port 41 and the axial ejection port 42 are alternately arranged along the circumferential direction C, and the flow blocking ring radial window 53 and the flow blocking ring axial window 54 are located in the same area. However, the present application is not limited thereto, and in other possible embodiments, the radial ejection port 41 and the axial ejection port 42 can be arranged in alignment along the circumferential direction C, and the flow blocking ring radial window 53 and the flow blocking ring axial window 54 can be alternately arranged. The radial ejection port 41 and the axial ejection port 42 can be staggered with the vane 2 in the circumferential direction C.

[0095] It should be understood that at least part of the aspects or features of the above-mentioned embodiments, examples or examples can be appropriately combined.

[0096] It can be understood that, in the present application, the number of components or members is one or more when the number of components or members is not particularly limited, and the plurality herein refers to two or more. For the case where the number of components or members is specifically described as, for example, two, three, four, etc. in the drawings and / or the description, the specific number is generally exemplary and not restrictive, and it can be understood as a plurality, i.e., two or more, but this does not mean that the present application excludes the case of one.

[0097] In the present application, unless otherwise explicitly stated or limited, the terms "mounting", "assembly", "assembly", "connection", "connection", "coupling", "connection", "abutment", "communication", "communication", "conduction", "fixing", "fastening", etc. should be understood broadly, for example, it can be direct or indirect. For example, in terms of connection, it can be a fixed connection, or a detachable connection, or integrated; it can be a mechanical connection, or an electrical connection; it can be directly connected, or indirectly connected through an intermediate medium, or the communication or interaction relationship between two elements, unless otherwise explicitly stated or limited. For example, in terms of communication / conduction, etc., it can be direct communication / conduction, or indirect communication / conduction via an intermediate medium. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0098] In the present application, unless otherwise explicitly stated or limited, one member is disposed in / installed in / located in / contained in / placed in another member, etc. can be any of the following two cases: a part or most of the one member is located in the other member; and the one member is completely contained in the other member.

[0099] Although the present application has been described in detail using the above embodiments, it is clear to those skilled in the art that the present application is not limited to the embodiments described in the present specification. The present application can be modified and implemented as a modified embodiment without departing from the spirit and scope of the present application defined by the claims. Therefore, the description in the present specification is for the purpose of illustration, and has no any limiting meaning on the present application.

Claims

1. A variable cycle afterburner with external matching fuel supply and injection switching, characterized in that: It includes a diverter ring (4) and a baffle ring (5), The diverter ring (4) is cylindrical, and the diverter ring (4) separates the inner flow channel (L1) and the outer flow channel (L2). The inner wall of the diverter ring (4) bulges radially outward to form an annular concave cavity (S). The concave cavity (S) is located at the downstream end of the diverter ring (4). The circumferential wall of the diverter ring (4) located at the upstream part of the concave cavity (S) is provided with a radial injection port (41). The front wall of the concave cavity (S) is provided with an axial injection port (42). A plurality of radial injection ports (41) and axial injection ports (42) are provided along the circumferential direction (C). The radial injection ports (41) and the axial injection ports (42) are alternately provided or aligned along the circumferential direction (C). The baffle ring (5) is sleeved on the radial outer side of the diverter ring (4), the baffle ring (5) comprises a plurality of baffle ring radial windows (53) and a plurality of baffle ring axial windows (54), the baffle ring (5) is capable of rotating relative to the diverter ring (4) along the circumferential direction (C), and the baffle ring (5) is capable of switching between a first baffle ring state and a second baffle ring state, wherein: In the first state of the baffle ring, the baffle ring radial window (53) and the radial injection port (41) at least partially overlap, and the axial injection port (42) is blocked by the baffle ring (5). In the second state of the baffle ring, the baffle ring axial window (54) and the axial injection port (42) at least partially overlap, and the radial injection port (41) is blocked by the baffle ring (5).

2. The variable cycle afterburner with external matching fuel supply and injection switching according to claim 1 is characterized in that: The concave cavity (S) includes a concave cavity front wall (S1), a concave cavity outer peripheral wall (S2) and a concave cavity rear wall (S3), the concave cavity outer peripheral wall (S2) extends in the axial direction (A) and the circumferential direction (C), the concave cavity front wall (S1) is connected to the upstream end of the concave cavity outer peripheral wall (S2), the concave cavity front wall (S1) extends in the radial direction (R) and the circumferential direction (C), the concave cavity front wall (S1) and the concave cavity outer peripheral wall (S2) are perpendicular to each other, the concave cavity rear wall (S3) is connected to the downstream end of the concave cavity outer peripheral wall (S2), the concave cavity rear wall (S3) is inclined relative to the axial direction (A), and the more the concave cavity rear wall (S3) extends toward the downstream side, the more it inclines radially inward.

3. The variable cycle afterburner with external matching fuel supply and injection switching according to claim 1 is characterized in that: The baffle ring (5) comprises an axial extension portion (51) and a radial extension portion (52), wherein the axial extension portion (51) extends in an axial direction (A) and a circumferential direction (C), and the baffle ring radial window (53) is provided on the axial extension portion (51), and the radial extension portion (52) extends in a radial direction (R) and a circumferential direction (C), and the baffle ring axial window (54) is provided on the radial extension portion (52). In the circumferential direction (C), the radial injection port (41) and the axial injection port (42) are alternately arranged along the circumferential direction (C), and the baffle ring radial window (53) and the baffle ring axial window (54) are located in the same area; Alternatively, in the circumferential direction (C), the radial injection port (41) and the axial injection port (42) are aligned along the circumferential direction (C), and the baffle ring radial window (53) and the baffle ring axial window (54) are alternately arranged.

4. The variable cycle afterburner with external matching fuel supply and injection switching according to claim 1 is characterized in that: While the axial injection port (42) is kept blocked by the baffle ring (5), the overlap between the baffle ring radial window (53) and the radial injection port (41) can be adjusted between 0% and 100%. While the radial injection port (41) is kept blocked by the baffle ring (5), the overlap between the baffle ring axial window (54) and the axial injection port (42) can be adjusted between 0% and 100%.

5. The variable cycle afterburner with external matching fuel supply and injection switching according to claim 1 is characterized in that: In the circumferential direction (C), there is a gap between the radial injection port (41) and the axial injection port (42).

6. The variable cycle afterburner with external matching fuel supply and injection switching according to claim 1 is characterized in that: The afterburner chamber further comprises a plurality of support plates (2), wherein the plurality of support plates (2) are arranged along the circumferential direction (C) on the inner flow channel (L1). The radial injection port (41) and the support plate (2) are staggered in the circumferential direction (C), and the axial injection port (42) and the support plate (2) are located in the same circumferential region.

7. The variable cycle afterburner with external matching fuel supply and injection switching according to claim 6 is characterized in that: In the circumferential direction (C), the radial injection port (41), the axial injection port (42), the baffle ring radial window (53) and the baffle ring axial window (54) have the same length, and their circumferential length is one third of the staggered angle between two adjacent support plates (2).

8. The variable cycle afterburner with external matching fuel supply and injection switching according to claim 6 is characterized in that: An oil spray rod (21) is provided inside the support plate (2), and a plurality of oil spray nozzles are connected to the oil spray rod (21), and the oil spray nozzles are configured to spray oil in a direction perpendicular to the support plate (2).

9. The variable cycle afterburner with external matching fuel supply and injection switching according to claim 2 is characterized in that: The afterburner chamber further comprises an adjustable ejector (7), The adjustable ejector (7) is arranged on the downstream side of the diverter ring (4), and the adjustable ejector (7) is movable in the axial direction (A) relative to the diverter ring (4). An adjustable outer ejection channel (I3) is formed between the adjustable ejector (7) and the rear wall (S3) of the cavity, and the opening of the adjustable outer ejection channel (I3) can be adjusted by the adjustable ejector (7) moving along the axial direction (A).

10. The variable cycle afterburner with external matching fuel supply and injection switching according to claim 2, characterized in that: The angle (θ) of the cavity rear wall (S3) relative to the axial direction (A) is 20 to 40 degrees.

Images