A variable cycle engine afterburner

Abstract

The application provides a reheat combustor applied to a variable cycle engine, which comprises a casing, a center cone, a splitter ring, an afterbypass ejector, an inner bypass stabilizer, a shockproof heat shield and an outer bypass stabilizer. The splitter ring, the afterbypass ejector and the casing form an outer bypass area, the center cone and the splitter ring form an inner bypass area, and the inner bypass area and the outer bypass area are respectively provided with a flame stabilizer for oil supply and combustion. By adjusting the position of the afterbypass ejector, the minimum flow area of the outer bypass area can be selectively reduced to make the reheat combustor realize a double outer bypass working mode, or the minimum flow area of the outer bypass area can be increased to make the reheat combustor realize a triple outer bypass working mode. Meanwhile, the structure of the outer bypass stabilizer designed in the application can realize the pre-mixing of the inner bypass hot gas and fuel, and promote the evaporation of the fuel. The application can adapt to the case that the range of the bypass ratio of the reheat combustor of the variable cycle engine is too large, improve the combustion efficiency and take into account the flow loss.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of aerospace, and relates to a variable cycle engine, in particular to a variable cycle engine applied to a variable cycle engine. BACKGROUND

[0002] Variable cycle engine (VCE) refers to changing the thermal cycle parameters by changing the positions of multiple adjustable geometry mechanisms according to different task requirements, so that the engine obtains optimal performance at different speed and height points within the envelope. Adaptive cycle engine (ACE) is a main research direction of the current sixth generation of military aviation engines, and is an advanced model developed on the basis of the variable cycle engine. Compared with the variable cycle engine, the adaptive cycle engine can automatically change the flow and pressure ratio of the fan and the core engine, and has stronger adaptability to different working modes. However, the current adaptive cycle engine lacks the structural design of the afterburner that can balance the combustion efficiency and reduce the flow loss, which restricts the development of the adaptive cycle engine. SUMMARY

[0003] In view of this, the present application provides a variable cycle engine applied to an afterburner, which can be applied to a scene with large change of the bypass ratio of the three-outer-bypass adaptive cycle engine, overcomes the technical defects of the traditional afterburner, and balances the flow loss while improving the combustion efficiency of the afterburner in the three-outer-bypass working mode.

[0004] The present application provides an afterburner applied to a variable cycle engine, the afterburner comprising:

[0005] a casing;

[0006] a center cone arranged along a central axis of the casing;

[0007] a splitter ring arranged annularly outside the center cone, which divides the gas in the afterburner into an inner-bypass area between the center cone and the casing and an outer-bypass area between the casing and the center cone; and

[0008] a rear-bypass ejector arranged coaxially inside the casing and annularly outside the splitter ring;

[0009] wherein an outer side surface of the splitter ring comprises a first inclined surface portion inclined inwardly in the axial direction, an inner side surface of the rear-bypass ejector comprises a second inclined surface portion inclined inwardly in the axial direction, and the rear-bypass ejector is configured to be movable in the axial direction, so as to change the minimum flow area of the outer-bypass area by adjusting the position of the first inclined surface portion relative to the second inclined surface portion according to the working condition requirement of the variable cycle engine.

[0010] Preferably, the second ramp portion of the aft-bypass ejector and the first ramp portion of the splitter ring are parallel.

[0011] Preferably, the inner side surface of the aft-bypass ejector further comprises a third ramp portion inclined axially outward, the third ramp portion being located at the rear side of the second ramp portion.

[0012] Preferably, the aft-bypass ejector and the first ramp portion of the splitter ring constitute a transition section in the outer-bypass region.

[0013] Preferably, the outer side surface of the splitter ring further comprises an annular portion extending axially, the annular portion being located at the front side of the first ramp portion.

[0014] Preferably, further comprising an outer-bypass stabilizer, the outer-bypass stabilizer being arranged at the splitter ring trailing edge and located at the rear side of the aft-bypass ejector, and the outer-bypass stabilizer being spacedly arranged at the inner side of the casing.

[0015] Preferably, the outer-bypass stabilizer comprises:

[0016] a stabilizer shell in a housing structure, connected to the rear end of the splitter ring;

[0017] an evaporation cavity in a cavity structure, arranged inside the stabilizer shell, for realizing fuel evaporation;

[0018] a bleed air ring arranged at the front end of the evaporation cavity and spacedly located at the inner side of the rear end of the splitter ring, so as to build an airflow passage between the bleed air ring, the stabilizer shell and the splitter ring to introduce inner-bypass hot gas; and

[0019] an oil guide pipe in a tubular structure, arranged inside the outer-bypass stabilizer to spray fuel;

[0020] wherein part of the inner-bypass gas entering from the airflow passage enters the evaporation cavity to promote the premixing and pre-evaporation of the inner-bypass gas and the fuel inside the evaporation cavity.

[0021] Preferably, the evaporation cavity is in a right trapezoidal structure in a cross section perpendicular to the circumferential direction, the upper base and the lower base extending axially, and the non-right-angle side waist being inclined axially outward, the stabilizer shell being spacedly arranged at the front side of the non-right-angle side waist and the outer side of the upper base of the evaporation cavity.

[0022] Preferably, the evaporation cavity is provided with circumferential oil injection holes on both sides in the circumferential direction, the circumferential oil injection holes are arranged in the radial direction and uniformly distributed on both sides of the evaporation cavity in the circumferential direction, and the upper bottom surface and the lower bottom surface of the evaporation cavity are provided with radial oil injection holes, and the circumferential oil injection holes and the radial oil injection holes are configured to uniformly inject evaporation oil mist around the evaporation cavity.

[0023] Preferably, the afterburner further comprises:

[0024] A short-content radial stabilizer is arranged inside the splitter ring, a first oil injection rod is arranged inside the short-content radial stabilizer, and a plurality of first oil injection holes for selectively spraying fuel outward are arranged on the surface of the short-content radial stabilizer.

[0025] A long-content radial stabilizer is arranged between the center cone and the splitter ring and is arranged in a circumferential staggered manner with the short-content radial stabilizer, a second oil injection rod is arranged inside the long-content radial stabilizer, and a plurality of second oil injection holes for selectively spraying fuel outward are arranged on the surface of the long-content radial stabilizer.

[0026] The advantages of the present application include:

[0027] The conventional afterburner cannot adapt to the characteristics of the adaptive cycle engine with a large change (0.2-1.0) in the bypass ratio, while in the structure of the afterburner designed in the present application, the change of the minimum flow area of the outer bypass region is controlled by the position of the rear bypass ejector, the minimum flow area of the outer bypass region is reduced by matching the rear bypass ejector with the splitter ring in the case of small outer bypass flow in the dual outer bypass mode, the flow area is increased in the transition section to slow down the airflow, and the minimum flow area formed by the rear bypass ejector and the splitter ring meets the overall design requirements; in the case of large outer bypass flow in the three outer bypass mode, the minimum flow area of the transition section inlet outer bypass region is increased by matching the rear bypass ejector with the splitter ring, and then the airflow is slowed down in the transition section to ensure that the minimum flow area of the outer bypass meets the overall design requirements, while the outer bypass structure is smooth and the along-the-way loss of the outer bypass airflow is reduced.

[0028] The present application designs to arrange stabilizers in the inner and outer bypasses to realize separate combustion of the inner and outer bypasses, compared with the afterburner that mixes the inner and outer bypass airflows first and then organizes combustion, the inflow conditions of the outer bypass stabilizer in the afterburner of the present application are more stable, the inner and outer bypasses supply oil separately to organize combustion, the oil supply design is more flexible, and the design of the parallel flow afterburner is simpler.

[0029] The outer bypass stabilizer in the present application generates a backflow area downstream of the stabilizer through the stabilizer shell; and the inner bypass hot gas is introduced through the air injection ring, part of which is pre-mixed with the oil in the evaporation cavity, the oil inside the evaporation cavity is pre-evaporated, and then the oil is uniformly injected around by the oil injection holes arranged on the convex evaporation cavity, thereby improving the combustion efficiency of the combustion organized by the rear edge of the stabilizer.

[0030] Compared with traditional mixed-flow afterburner, the afterburner designed in this invention eliminates the mixing of inner and outer bypass airflows before combustion, thus reducing flow losses caused by airflow mixing in non-afterburner states.

[0031] The afterburner structure designed in this invention solves the problem of a wide range of bypass ratio variations, achieving effective combustion after the bypass stabilizer and improving the combustion efficiency after the bypass stabilizer; at the same time, the bypass structure designed in this invention effectively reduces airflow loss and has a high total pressure recovery coefficient. Attached Figure Description

[0032] Figure 1 A schematic cross-sectional view of the three-bypass adaptive cycle engine used in the afterburner of the present invention in the dual-bypass operating mode, parallel to the axial direction.

[0033] Figure 2 A schematic cross-sectional view of the three-bypass adaptive cycle engine used in the afterburner of the present invention in the three-bypass operating mode, parallel to the axial direction.

[0034] Figure 3 This is a schematic cross-sectional view of the afterburner of the present invention, located behind the bypass stabilizer along a direction perpendicular to the axial direction.

[0035] Figure 4 In this invention, the afterburner is in dual-outer-broom operating mode along... Figure 3 A schematic diagram of the cross-sectional structure parallel to the axial direction at angle B in the middle;

[0036] Figure 5 In this invention, the afterburner is in the three-outer-blower operating mode along... Figure 3 A schematic diagram of the cross-sectional structure parallel to the axial direction at angle B in the middle;

[0037] Figure 6 This is a schematic diagram of the rear duct ejector of the afterburner of the present invention.

[0038] Figure 7 This is a schematic diagram of the short-inner radial stabilizer of the afterburner of the present invention;

[0039] Figure 8 This is a schematic diagram of the structure of the radial stabilizer within the long inner cavity of the afterburner of the present invention;

[0040] Figure 9 This is a schematic diagram of the external bypass stabilizer of the afterburner of the present invention.

[0041] Figure label:

[0042] 1 -casing, 2 -center cone, 3 -splitter ring, 31 -annular part, 32 -first inclined surface part, 4 -aft -duct ejector, 41 -second inclined surface part, 42 -third inclined surface part, 5 -short inner-duct radial stabilizer, 51 -first oil injection hole, 52 -first oil injection rod, 6 -long inner-duct radial stabilizer, 61 -second oil injection hole, 62 -second oil injection rod, 7 -anti-vibration heat shield, 8 -outer-duct stabilizer, 81 -stabilizer shell, 82 -evaporation cavity, 83 -bleed air ring, 84 -oil guide pipe, 85 -circumferential oil injection hole, 86 -radial oil injection hole;

[0043] A1 -outer-duct region minimum flow area, a -inner-duct region, b -outer-duct region, d1 -first outer-duct passage, d2 -second outer-duct passage, d3 -third outer-duct passage, d4 -inner-duct passage. DETAILED DESCRIPTION

[0044] The application will be described in detail below with reference to the drawings and specific embodiments.

[0045] It is to be understood that the descriptions of the example embodiments are merely illustrative and do not limit the application and its application or use in any way. The application can be implemented in many different forms, not limited to the embodiments herein. These embodiments are provided to make the application clear and complete, and to fully express the scope of the application to those skilled in the art. It should be noted that: unless otherwise specified, the relative arrangement of components and steps set forth in these embodiments should be interpreted as merely illustrative, and not as a limitation.

[0046] In order to facilitate the definition of the afterburner, the direction of the casing center axis is defined as the axial direction, and the direction along the inlet of the afterburner is defined as the forward direction, and the direction along the outlet of the afterburner is defined as the rearward direction; the direction perpendicular to the axial direction is defined as the radial direction, the direction close to the axis is defined as the inward direction, and the direction away from the axis is defined as the outward direction; the direction around the circumference of the central axis is defined as the circumferential direction, and in the direction of the afterburner outlet looking at the inlet, the clockwise circumferential direction along the central axis is defined as the clockwise direction, and the counterclockwise circumferential direction is defined as the counterclockwise direction.

[0047] The applicant found that the current double-outer-duct self-adaptive cycle engine can realize the afterburner scheme with small or medium bypass ratio according to the outer-duct flow, and on this basis, in order to further improve the variable cycle capability of the self-adaptive cycle engine, the current triple-outer-duct self-adaptive cycle engine has a double-outer-duct working mode and a triple-outer-duct working mode. As shown in Figure 1 As shown in FIG. 1, in the double-outer-duct working mode, the second outer-duct passage is closed, the high-temperature gas flow of the inner-duct and the low-temperature gas flow of the first outer-duct are mixed at the aft-duct ejector after the splitter ring, and the third outer-duct gas flow is directly discharged into the atmosphere; as shown in Figure 2As shown, in the three-outer-duct working mode, the first outer-duct and the second outer-duct low-temperature air flows are mixed after the front-duct ejector, and then mixed with the inner-duct high-temperature air flow after the rear-duct ejector behind the splitter ring, and the third outer-duct air flow is directly discharged into the atmosphere.

[0048] Since the inner-duct and outer-duct air flows in different working modes of the three-outer-duct adaptive cycle engine are mixed after the rear-duct ejector behind the splitter ring, the duct ratio changes greatly (0.2-1.0), and the combustion efficiency of the inner-duct is relatively low, and it is difficult to efficiently organize combustion under the condition of a large duct ratio. At present, the flow loss in the mixing process of the inner-duct and outer-duct air flows is large due to the designed structure of the rotating rear-duct ejector.

[0049] In view of this, in the technical scheme of one aspect of the present application, the rear-duct ejector is designed to have a certain inclined angle and a ring-shaped arrangement, and the inclined angle of the ejector is parallel to the design inclined angle of the splitter ring, forming a parallel outer-duct air flow channel for controlling the minimum flow area A1 of the outer-duct region in the three-outer-duct mode.

[0050] Specifically, in order to realize effective combustion after the outer-duct stabilizer in the three-outer-duct working mode, a afterburner applied to a variable cycle engine is designed in this paper, which comprises:

[0051] The casing 1 is basically cylindrical and is arranged at the outermost side of the central axis, mainly serving to limit the flow range of the air flow and support the frame.

[0052] The center cone 2 is arranged along the central axis of the casing 1 and has a tapered structure with a gradually shrinking cross-sectional area in the axial direction. The center cone 2 has a similar function to the casing 1, mainly serving to limit the flow range of the air flow and support the frame.

[0053] The splitter ring 3 has a ring-shaped structure and is arranged around the inside of the casing 1. The high-temperature inner-duct air flow after the turbine flows through the inside of the splitter ring 3, and the low-temperature outer-duct air flow flows through the outside of the splitter ring 3. At the same time, the outer profile of the splitter ring 3 has a certain inclined angle in the axial middle part. Therefore, the function of the splitter ring 3 is to separate the turbine air flow into the inner-duct region and the outer-duct region.

[0054] The rear-duct ejector 4 is in a ring structure, arranged along the central axis of the casing 1, and arranged on the inside of the casing 1, and forms an outer-duct area with the channel formed by the casing 1 and the splitter ring 3. As can be seen from the front view, the rear-duct ejector 4 has two parts with a certain inclination angle, the angle of the second inclined part 41 is the same as the angle of the first inclined part 32 of the splitter ring 3, and the rear-duct ejector 4 and the first inclined part 32 of the splitter ring 3 form a transition section b1. At the same time, a transmission structure is arranged to adjust the position of the rear-duct ejector 4, so that the rear-duct ejector 4 can move axially forward and backward. The function of the rear-duct ejector 4 is to limit the flow range of the outer-duct airflow, and at the same time, the relative position with the splitter ring 3 can be adjusted according to the engine working mode (double-outer-duct or triple-outer-duct mode) to realize the reduction or increase of the minimum flow area A1 of the outer-duct area.

[0055] The short inner-duct radial stabilizer 5 is arranged on the inside of the splitter ring 3 and arranged circumferentially, and functions to form a stable recirculation zone by the bluff body structure for the high-temperature airflow entering the inner-duct channel, and at the same time, part of the high-temperature burned products are recirculated to continuously ignite the unburned airflow to achieve stable flame effect. The first oil injection hole 51 for injecting fuel outward is arranged on the side surface, and the first oil injection rod 52 for introducing fuel is arranged inside. After the fuel is injected from the first oil injection hole, it is mixed with the inner-duct high-temperature hot air and ignited at the stabilizer trailing edge.

[0056] The long inner-duct radial stabilizer 6 is arranged on the inside of the splitter ring 3 and arranged circumferentially staggered with the short inner-duct stabilizer 5, and functions to divide the airflow entering the inner-duct channel into an open channel, so that the high-temperature airflow passes through the bluff body structure to form a stable recirculation zone, and at the same time, part of the high-temperature burned products are recirculated to continuously ignite the unburned airflow to achieve stable flame effect. The second oil injection hole 61 for injecting fuel outward is arranged on the side surface, and the second oil injection rod 62 for introducing fuel is arranged inside. After the fuel is injected from the first oil injection hole, it is mixed with the inner-duct high-temperature hot air and ignited at the stabilizer trailing edge.

[0057] The shockproof heat shield 7 is arranged between the outer-duct stabilizer 6 and the casing 1, and is arranged in a spaced manner with the casing 1. The basic structure is a porous thin plate cylinder structure, and has a certain distance with the outer shell to form an annular cooling channel, and functions to prevent heat insulation and prevent oscillating combustion.

[0058] The outer bypass stabilizer 8, located inside the casing 1 and behind the rear bypass ejector 4, includes an outer stabilizer housing 81, an internal evaporator chamber 82, a bleed air ring 83, and an oil guide pipe 84. The outer stabilizer housing 81 has a radially arranged cavity structure with a certain circumferential width in a cross-section perpendicular to the axial direction. Multiple stabilizer housings are evenly arranged circumferentially to divide the low-temperature bypass airflow into an unclosed channel, forming a low-speed recirculation zone at the trailing edge of the support plate, which aids combustion. The internal evaporator chamber 82 has a convex shape in a cross-section perpendicular to the axial direction and is evenly arranged circumferentially. Its function is to utilize high... The fuel is evaporated by the warm internal airflow, and then the fuel is sprayed out from all sides to achieve uniform fuel mist distribution. The bleed air ring 83 is set at the front end of the evaporation chamber 82 and is located at intervals on the inner side of the rear end of the flow divider ring 3, thereby constructing an airflow channel between the bleed air ring 83, the stabilizer housing 81 and the flow divider ring 3 to introduce the internal hot air, so that part of it is pre-mixed with the fuel in the evaporation chamber and pre-evaporated. The fuel guide pipe 84 is a fuel supply channel that introduces fuel into the evaporation chamber, so that the fuel evaporates inside the evaporation chamber, and then is sprayed out from the circumferential fuel injection hole 85 and radial fuel injection hole 86 arranged circumferentially at the rear of the evaporation chamber, and mixed with the external airflow to achieve combustion.

[0059] like Figure 1 , Figure 2 As shown in the diagram, the black-filled blades fixedly connected to the central shaft are rotor blades in the conventional sense, while the white-filled blades are stator blades in the conventional sense. d1, d2, and d3 represent the first, second, and third bypass channels, respectively, and d4 is the inner bypass channel. Furthermore, regulating mechanisms, such as mode selection valves, front bypass ejectors, and rear bypass ejectors, are installed at the outlets of the first, second, and third bypass channels d1 and d3. These regulating mechanisms work together to adjust the thermodynamic cycle parameters of the adaptive cycle engine. In the dual-bypass operating mode, the regulating valve controls the inlet of the second bypass channel d2 to be closed, and the airflow flows through the first bypass channel d1 and the third bypass channel d3. The airflow from the first bypass channel d1 and the airflow from the inner bypass channel d4 mix at the rear bypass ejector. At this time, the engine bypass is relatively small. In the triple-bypass operating mode, the second bypass channel d2 is opened, and the airflow flows through the first bypass channel d1, the second bypass channel d2, and the third bypass channel d3. The airflow from the first bypass channel d1 and the second bypass channel d2 first mixes at the front bypass ejector, and the mixed bypass airflow mixes with the airflow from the inner bypass channel d4 at the rear bypass ejector. At this time, the engine bypass is relatively large.

[0060] Figure 4The structural schematic diagram of the afterburner in the application under the double-outer-duct working mode of the adaptive cycle engine is shown in the figure. After entering the inlet of the afterburner, the airflow enters the outer-duct area formed by the casing and the splitter ring. The airflow enters the adapter section inlet A1 formed by the after-duct ejector and the splitter ring. The expansion and deceleration of the airflow are realized in the adapter section. The airflow flows through the outer-duct stabilizer and is cut into circumferentially discontinuous parts. The airflow speed is reduced from the high speed at the inlet of the afterburner to the low speed that can organize combustion. Finally, the combustion is realized after the outer-duct stabilizer. The fuel is arranged at the following positions in the process: the front side of the outer-duct stabilizer, to realize the mixing of the outer-duct airflow and the fuel near the outer-duct stabilizer; the position of the oil guide pipe of the outer-duct stabilizer, to spray the fuel into the evaporation cavity, realize evaporation under the action of the inner-duct hot gas, and then spray out from the oil injection holes opened on the two sides and the upper and lower of the outer-duct stabilizer.

[0061] Figure 5 The structural schematic diagram of the afterburner in the application under the three-outer-duct working mode of the adaptive cycle engine is shown in the figure. The difference from the double-outer-duct mode is that the minimum flow area A1' of the outer-duct area in the three-outer-duct mode is greater than A1 in the double-outer-duct mode. The airflow has a smaller change in the flow area in the outer-duct. At this time, the larger bypass ratio condition is adapted. The expansion and deceleration are realized in the adapter stage. At this time, the outer-duct area is relatively smooth, the cross-sectional area of the channel changes little along the flow direction, the flow loss of the outer-duct airflow is smaller, and the combustion is effectively organized after the outer-duct stabilizer.

[0062] As shown in the figure, Figure 6 The structural schematic diagram of the after-duct ejector is shown in the figure. The after-duct ejector is annular structure, and has transmission structures at the front end and the end in the axial direction. The position of the after-duct ejector relative to the splitter ring can be moved forward and backward in the axial direction, so as to realize the change of the minimum flow area of the outer-duct area formed by the after-duct ejector and the splitter ring according to the working mode of the adaptive cycle engine.

[0063] Figure 7 、 Figure 8 The short inner-duct radial stabilizer and the long inner-duct radial stabilizer are shown in the figure. As shown in the figure, the inner-duct radial stabilizer is arranged in a hollow structure. The oil injection rod is arranged inside the inner-duct radial stabilizer. The oil injection holes are arranged on the side surface of the inner-duct radial stabilizer corresponding to the positions of the oil injection holes on the oil injection rod, for injecting fuel to both sides, mixing with the inner-duct high-temperature gas, and realizing combustion after the inner-duct radial stabilizer.

[0064] As shown in the figure, Figure 9The outer containment stabilizer structure schematic diagram is shown, the outer containment stabilizer is arranged at the axial rear side of the rear channel ejector, the structure is a convex letter type, is arranged in a circumferential ring shape, is combined from two parts: one part is the stabilizer shell, the main view is shown as a right-angled trapezoidal shape, and the function is to form a backflow area behind the blunt body; one part is the fuel evaporation cavity, a plurality of oil injection holes are arranged on the upper and lower ends and the side, for injecting fuel; one part is the cylindrical structure arranged inside the splitter ring, and the splitter ring forms an air injection ring, after the inner containment hot gas passes through the channel, part of the inner containment hot gas enters the evaporation cavity and mixes with the fuel, so that the fuel is pre-evaporated and then sprayed out from the oil injection hole arranged at the tail of the evaporation cavity, and the other part is sprayed out from the gap channel formed by the evaporation cavity and the stabilizer shell to the rear of the stabilizer, and participates in combustion together with the outer containment airflow; the oil injection point is arranged at the oil guide pipe, the fuel is injected into the fuel evaporation cavity, is evaporated, and is sprayed out from the oil injection hole arranged at the tail of the stabilizer, and stable combustion is realized at the rear end of the outer containment stabilizer.

[0065] The beneficial technical effects of the present application at least include:

[0066] In the double-outer-containment working mode, the minimum flow area of the outer containment region is reduced by the rear channel ejector structure designed in the application, so as to adapt to the working condition that the outer containment flow is small in the double-outer-containment working mode, the outer containment airflow realizes pressure recovery and speed reduction in the adapter section, and the requirement of effective combustion on the Mach number of the airflow is met.

[0067] In the triple-outer-containment working mode, the minimum flow area of the outer containment region is increased by the rear channel ejector structure designed in the application, so as to adapt to the requirement of pressure recovery and speed reduction of the outer containment airflow in the triple-outer-containment working mode, effective combustion is realized at the tail edge of the outer containment stabilizer, the combustion efficiency is improved, and the flow loss is reduced.

[0068] For the design of the outer containment stabilizer, the inner containment high-temperature gas is introduced to pre-mix with the fuel, the fuel evaporation is promoted, the fuel is sprayed to the tail edge of the stabilizer through the oil injection hole, and the fuel is mixed with part of the inner containment hot gas mixture, so that full combustion is realized after the fuel is mixed with the outer containment airflow, and the combustion efficiency is improved.

[0069] So far, some specific embodiments of the present application have been described in detail through examples, but those skilled in the art should understand that the above examples are only for illustration, and are not intended to limit the scope of the present application. Those skilled in the art should understand that the above embodiments can be modified or some technical features can be replaced equivalently without departing from the scope and spirit of the present application. The scope of the present application is defined by the appended claims.

Claims

1. An afterburner chamber for use in a variable cycle engine, characterized in that, The afterburner includes: Casing (1); A central cone (2) is provided along the central axis of the casing (1); A flow divider ring (3), arranged around the outside of the central cone (2), divides the gas in the afterburner chamber into an inner region (a) between the central cone (2) and an outer region (b) between the casing (1); and The rear duct ejector (4) has a ring-shaped structure, is coaxially disposed inside the casing (1), and is arranged around the outside of the diverter ring (3); The outer surface of the diverter ring (3) includes a first inclined portion (32) that is inclined inward along the axial direction, and the inner surface of the rear duct ejector (4) includes a second inclined portion (41) that is inclined inward along the axial direction. The rear duct ejector (4) is configured to be movable along the axial direction, thereby changing the minimum flow area of ​​the outer duct region (b) by adjusting the position of the first inclined portion (32) relative to the second inclined portion (41) according to the operating conditions of the variable cycle engine.

2. The afterburner according to claim 1, characterized in that, The second inclined portion (41) of the rear duct ejector (4) and the first inclined portion (32) of the diverter ring (3) are parallel.

3. The afterburner according to claim 1, characterized in that, The inner side of the rear duct ejector (4) also includes a third inclined section (42) that is inclined outward along the axial direction, and the third inclined section (42) is located behind the second inclined section (41).

4. The afterburner according to claim 3, characterized in that, The rear duct ejector (4) and the first inclined section (32) of the diversion ring (3) constitute the transition section (b1) in the outer duct region (b).

5. The afterburner according to claim 1, characterized in that, The outer side of the diversion ring (3) also includes an annular portion (31) extending axially, the annular portion (31) being located in front of the first inclined portion (32).

6. The afterburner according to claim 1, characterized in that, It also includes an outer bypass stabilizer (8), which is disposed at the tail edge of the splitter ring (3) and located on the rear side of the rear duct ejector (4), and the outer bypass stabilizer (8) is disposed at intervals on the inner side of the casing (1).

7. The afterburner according to claim 6, characterized in that, The bypass stabilizer (8) includes: The stabilizer housing (81) has a shell structure and is connected to the rear end of the diversion ring (3); The evaporation chamber (82) has a cavity structure and is located inside the stabilizer housing (81) to realize fuel evaporation; An air intake ring (83) is disposed at the front end of the evaporation chamber (82) and spaced apart inside the rear end of the diversion ring (3), thereby constructing an airflow channel between the air intake ring (83), the stabilizer housing (81), and the diversion ring (3) to introduce internal hot air; and The oil guide pipe (84) has a tubular structure and is installed inside the outer bypass stabilizer (8) for injecting fuel; In this process, a portion of the internal combustion gas entering from the airflow channel enters the evaporation chamber to promote the premixing and pre-evaporation of the internal combustion gas and the fuel oil within the evaporation chamber.

8. The afterburner according to claim 7, characterized in that, The evaporation cavity (82) has a right-angled trapezoidal structure in a cross section perpendicular to the circumference, with its upper and lower bases extending axially and its non-right-angled sides inclined outward along the axial direction. The stabilizer housing (81) is spaced over the front side of the non-right-angled sides and the outside of the upper base of the evaporation cavity (82).

9. The afterburner according to claim 8, characterized in that, The evaporation chamber (82) is provided with circumferential oil spray holes (85) on both sides along the circumference. The circumferential oil spray holes are arranged radially and evenly distributed on both sides of the circumference of the evaporation chamber (82). The upper and lower bottom surfaces of the evaporation chamber (82) are provided with radial oil spray holes (86). The circumferential oil spray holes (85) and the radial oil spray holes are configured to evenly spray evaporated oil mist around the evaporation chamber (82).

10. The afterburner according to claim 1, characterized in that, Also includes: A short-inner radial stabilizer (5) is disposed inside the split ring (3), with a first fuel injection rod (52) disposed inside and multiple first fuel injection holes (51) selectively injecting fuel outward on its surface; The long-inner radial stabilizer (6) is disposed between the central cone (2) and the split ring (3) and is staggered with the short-inner radial stabilizer (5) in the circumferential direction. It has a second fuel injection rod (62) inside and multiple second fuel injection holes (61) that can selectively inject fuel outward on its surface.

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