A flap-type turbine blade structure and variable cycle engine

Abstract

The present application relates to the technical field of turbine blades of aero-engine or heavy gas turbine, and particularly relates to a new type of flap turbine blade structure and a variable cycle engine, which comprises a connecting assembly, a cover plate, a flap blade, an end wall and a leading edge fixed blade, the end wall is provided with an end wall slit, the flap blade passes through the end wall and moves in the end wall, the leading edge fixed blade is seamlessly connected with the end wall, the cover plate above the flap blade and the sealing ring jointly act on the flap blade, the gap between the top part and the bottom part of the flap blade and the leading edge fixed blade is eliminated, the generation of blade gap leakage vortex is effectively avoided, the sealing effect of the sealing ring and the tight sealing cold gas effectively prevents the high-temperature gas leakage at the end wall slit, the total pressure loss and the high-temperature gas backflow caused by the top gap and the bottom gap of the existing variable cycle turbine blade are solved, the safety and stability are improved, the fuel consumption rate of the aero-engine is reduced, and the economic benefit is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of aero-engine turbine blades or heavy gas turbine turbine blades, in particular to a new type of flap turbine blade structure and a variable cycle engine, and especially to a new type of flap turbine blade structure and a variable cycle engine suitable for a variable cycle engine. BACKGROUND

[0002] The variable cycle engine has excellent airflow regulation capacity, good inherent cycle performance and low oil consumption characteristics. It is widely used in many fields, especially in the aviation and energy industries. The variable cycle turbine is an important part of the variable cycle engine, and the variable cycle turbine blade is proved to be the best variable cycle turbine regulation method. In order to improve the efficiency of the variable cycle engine under non-design conditions, scientists are actively researching and improving the variable cycle turbine blade.

[0003] Reference Figure 1 In the traditional dynamic adjustment process of the variable cycle turbine blade, in order to ensure that the dynamic adjustment process of the variable cycle turbine blade can be carried out smoothly, there is a gap between the blade and the end wall. In a common variable cycle turbine device, the height of the blade h v,t is less than the height of the end wall h e,t There is a gap between the tip and the end wall. Since the suction surface and the pressure surface have a pressure difference, a leakage flow is formed in the gap, and the leakage flow and the main flow are mixed to form a leakage vortex, thereby causing a loss and adversely affecting the turbine. High-temperature gas can leak back through the end wall gap, increasing the thermal stress of the turbine hot end components and posing a great threat to the safe and stable operation of the turbine. SUMMARY

[0004] In view of the problem of large total pressure loss and low safety and stability caused by high-temperature gas backflow of the variable cycle turbine blade in the prior art, the present application provides a new type of flap turbine blade structure and a variable cycle engine.

[0005] To achieve the above-mentioned purpose, the present application adopts the following technical solutions:

[0006] The present application provides a new type of flap turbine blade structure, which comprises a connecting assembly, a cover plate, a flap blade, an end wall and a leading edge fixed blade; one end of the connecting assembly is connected to the rocker arm of the engine, and the other end is connected to the cover plate and the flap blade in turn; the end wall is provided with an end wall slot, and the flap blade passes through the end wall slot and moves freely in the end wall slot; the end wall is provided with a sealing ring along the outside of the end wall slot; the leading edge fixed blade is seamlessly connected to the side of the end wall away from the cover plate; and the side of the cover plate close to the connecting assembly is connected to the sealing cold gas.

[0007] Optionally, the shape of the end wall slit is the same as the projected profile shape swept by the flap blade during movement.

[0008] Optionally, the area of the end wall slit is greater than the projected profile area swept by the flap blade during movement.

[0009] Optionally, an end wall groove is arranged on the end face of the end wall near the side of the cover plate for mounting a sealing ring.

[0010] Optionally, the radius of the end wall groove is equal to the radius of the sealing ring, and the radius of the sealing ring is equal to the distance between the cover plate and the end wall.

[0011] Optionally, the side of the end wall connected with the leading edge fixed blade is in an I-shaped structure.

[0012] Optionally, the area of the cover plate is greater than the area surrounded by the sealing ring, and the cover plate always covers the area surrounded by the sealing ring during movement of the flap blade.

[0013] Optionally, the height of the flap blade is greater than the height of the end wall.

[0014] Optionally, the material of the sealing ring is a high-temperature-resistant ceramic woven flexible fiber material.

[0015] The application also provides a variable cycle engine comprising the novel flap-type turbine blade structure.

[0016] Compared with the prior art, the application has the following beneficial effects:

[0017] The novel flap-type turbine blade structure comprises a connecting assembly, a cover plate, a flap blade, an end wall and a leading edge fixed blade; the connecting assembly is connected with a rocker arm of an engine, so that movement of the rocker arm drives movement of the connecting assembly; the connecting assembly is connected with the cover plate and the flap blade, thereby driving movement of the flap blade; the end wall slit is arranged on the end wall, so that the flap blade passes through the end wall slit and moves freely in the end wall slit; since the tip part of the leading edge fixed blade and the flap blade is free of tip gap, the generation of blade gap leakage vortex is effectively avoided, thereby reducing the flow loss and total pressure loss in the cascade passage; high-temperature gas passes through the leading edge fixed blade and the flap blade in sequence; since the end wall slit is arranged on the end wall, part of the high-temperature gas in the cascade passage leaks through the end wall slit; the cover plate arranged above the end wall slit can effectively reduce the leakage of high-temperature gas; the sealing ring and the sealing cold air flowing in from the gap around the cover plate and the gap around the flap blade can further effectively prevent the leakage of high-temperature gas, thereby protecting the safe and stable operation of the turbine components, reducing the flow loss in the cascade passage, improving the turbine efficiency, greatly reducing the fuel consumption rate of the aero-engine and increasing the economic benefit of the aero-engine.

[0018] The shape of the end wall slit is the same as the projected profile shape swept by the flap blade during movement, and the area of the end wall slit is greater than the projected profile area swept by the flap blade during movement, so that the flap blade is not hindered by the end wall during movement.

[0019] An end wall groove is arranged on the end face of the end wall close to the cover plate side, for mounting a sealing ring.

[0020] The radius of the end wall groove is equal to the radius of the sealing ring, so as to ensure that the sealing ring is installed in place and reliable.

[0021] The radius of the sealing ring is equal to the distance between the cover plate and the end wall, so as to avoid leakage of high-temperature combustion gas from the gap between the cover plate and the end wall, and reduce the influence of the sealing ring on the movement of the flap blade.

[0022] The side of the end wall connected with the leading edge fixed blade is in an I-shaped structure, so as to ensure that the stability and strength of the end wall structure meet the requirements.

[0023] The area of the cover plate is greater than the area surrounded by the sealing ring, and the cover plate always covers the area surrounded by the sealing ring during movement of the flap blade, so as to ensure that the cover plate always maintains effective sealing with the end wall during movement, avoid high-temperature combustion gas leaked from the end wall slit from flowing out from the gap between the end wall and the cover plate, and ensure the safe and stable operation of the turbine.

[0024] The height of the flap blade is greater than the height of the end wall, so as to avoid the leakage flow formed due to the existence of the tip clearance and the bottom clearance in the cascade channel, thereby avoiding the leakage vortex formed by the mixing of the leakage flow and the main flow, and achieving the purpose of reducing the leakage loss.

[0025] The material of the sealing ring is high-temperature-resistant ceramic woven flexible fiber material, which can ensure the sealing between the cover plate and the end wall, avoid the failure of the sealing ring due to high temperature, and ensure the stability of the sealing.

[0026] The application also provides a variable cycle engine comprising the novel flap type turbine blade structure. Through the arrangement of the novel flap type turbine blade structure, the airflow path is optimized, and the aerodynamic performance of the blade surface is enhanced, so that the engine can generate greater thrust under the same fuel consumption, and the combustion efficiency is improved. The engine has lower fuel consumption rate, higher fuel heat absorption rate, low failure rate, higher reliability and longer service life, so as to have stronger competitiveness, and occupy a more important position in the future aviation market. BRIEF DESCRIPTION OF DRAWINGS

[0027] Figure 1 It is a two-dimensional cross-sectional schematic view of a traditional turbine blade device.

[0028] Figure 2 An exploded view of a new flap type turbine blade structure of the present application.

[0029] Figure 3 A two-dimensional end wall structure diagram of a new flap type turbine blade structure movement process of the present application.

[0030] Figure 4 A cross-sectional schematic diagram before movement of a new flap type turbine blade structure of the present application.

[0031] Figure 5 A cross-sectional schematic diagram after movement of a new flap type turbine blade structure of the present application.

[0032] Wherein, 1 - connecting assembly, 2 - cover plate, 3 - flap blade, 4 - sealing ring, 5 - end wall slot, 6 - end wall, 7 - leading edge fixed blade, 8 - flap blade position at the end of rotation, 9 - end wall slot, 10 - end wall of traditional turbine structure, 11 - blade. DETAILED DESCRIPTION

[0033] In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the following will be combined with the drawings of the embodiments of the present application to make a clear and complete description of the technical solutions in the embodiments of the present application. Obviously, the described embodiments are some of the embodiments of the present application, rather than all the embodiments. The components of the embodiments of the present application described and shown in the drawings can be arranged and designed in various different configurations.

[0034] Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the claimed application, but only represents selected embodiments of the present application. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present application without creative labor are within the scope of protection of the present application.

[0035] It should be noted that: similar reference numbers and letters represent similar items in the following drawings, therefore, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings.

[0036] In the description of the embodiments of the present application, it should be noted that if the orientation or position relationship indicated by the terms "upper", "lower", "horizontal", "inner" and the like is based on the orientation or position relationship shown in the drawings, or is the orientation or position relationship when the product of the present application is usually placed, and is only for the convenience of describing the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the indicated device or element must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application. In addition, the terms "first", "second" and the like are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0037] In addition, if the term "horizontal" appears, it does not mean that the component must be absolutely horizontal, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0038] In the description of the embodiments of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "disposed," "installed," "connected," and "connected" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections or electrical connections; they can refer to direct connections or indirect connections through an intermediate medium; and they can refer to internal connections between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0039] The present invention will be further described in detail below with reference to specific embodiments, which are intended to explain the present invention rather than to limit it.

[0040] See also Figure 1 In the traditional variable cycle turbine blade dynamic adjustment process, in order to ensure that the variable cycle turbine blade dynamic adjustment process can proceed smoothly, there is a gap between the blade 11 and the end wall 10 of the traditional turbine structure. h v,t Less than end wall height h e,t The blade tips have tip clearances, and the blade base has base clearances. Due to the pressure differential between the suction and pressure surfaces, leakage flows form in these clearances. These leaks mix with the main flow, forming leakage vortices, which cause losses and adversely affect the turbine. High-temperature combustion gas can leak back through the endwall clearances, increasing thermal stress on the turbine's hot end components and posing a significant threat to safe and stable turbine operation.

[0041] To solve the problems existing in traditional turbine structures, see Figure 2The application discloses a novel flap type turbine blade structure, which comprises an end wall 6 and a connecting assembly 1 connected with an engine rocker arm, the connecting assembly 1 is sequentially connected with a cover plate 2 and a flap blade 3; the end wall 6 is provided with an end wall slit 9, the flap blade 3 passes through the end wall slit 9 and freely moves in the end wall slit 9, a leading edge fixed blade 7 is connected to one side of the end wall 6 away from the cover plate 2, and the leading edge fixed blade 7 is seamlessly connected with the end wall 6; a sealing ring 4 is arranged outside the end wall slit 9, the sealing ring 4 is located between the cover plate 2 and the end wall 6 and is used for sealing a gap between the cover plate 2 and the end wall 6; the cover plate 2 is provided with a seal cold gas on one side close to the connecting assembly 1, the seal cold gas is used for assisting the sealing ring 2 to seal the gap between the end wall 6 and the cover plate 2, preventing high-temperature gas from leaking through the end wall slit 9, ensuring effective movement of the structure, avoiding influence of leakage of the high-temperature gas on stability and service life of the engine and the like.

[0042] Since the leading edge fixed blade 7 and the tip portion and the bottom portion of the flap blade 3 in the flap type turbine blade structure do not have a tip gap, generation of blade gap leakage vortex is effectively avoided, thereby reducing flow loss and total pressure loss in a cascade channel; high-temperature gas passes through the leading edge fixed blade 7 and the flap blade 3 in sequence, part of the high-temperature gas in the cascade channel leaks through the end wall slit due to the end wall slit on the end wall 6, the cover plate 2 and the sealing ring 4 arranged above the end wall slit can effectively reduce leakage of the high-temperature gas, the sealing ring 4 and the seal cold gas flowing in from a gap around the cover plate 2 and a gap around the flap blade can further effectively prevent leakage of the high-temperature gas, safe and stable operation of turbine components can be ensured, flow loss in the cascade channel is reduced, and turbine efficiency is improved.

[0043] Embodiment 1

[0044] Reference Figure 2 The application discloses a novel flap type turbine blade structure, which comprises an end wall 6 and a connecting assembly 1 connected with an engine rocker arm, the connecting assembly 1 is sequentially connected with a cover plate 2 and a flap blade 3;

[0045] The end wall 6 is provided with an end wall slit 9, the flap blade 3 passes through the end wall slit 9 and freely moves in the end wall slit 9, the shape of the end wall slit 9 is same as a projection outline shape swept by the flap blade 3 in a movement process, and the area of the end wall slit 9 is greater than the projection outline area swept by the flap blade 3 in the movement process, so that movement of the flap blade 3 is not hindered by the end wall; the end wall 6 is connected with a leading edge fixed blade 7 on one side away from the cover plate 2, and the leading edge fixed blade 7 is seamlessly connected with the end wall 6; an end wall groove 5 is arranged on an end face of the end wall 6 close to the cover plate 2, a sealing ring 4 is installed in the end wall groove 5, and the end wall groove 5 surrounds the end wall slit 9; the cover plate 2 is provided with a seal cold gas on one side close to the connecting assembly 1.

[0046] Embodiment 2

[0047] Referring to Figure 2 The application discloses a novel flap type turbine blade structure, which comprises an end wall 6 and a connecting assembly 1 connected with an engine rocker arm, the connecting assembly 1 is sequentially connected with a cover plate 2 and a flap blade 3, and the height of the flap blade 3 is greater than the height of the end wall 6.

[0048] The end wall 6 is provided with an end wall slot 9, the flap blade 3 passes through the end wall slot 9 and freely moves in the end wall slot 9, the shape of the end wall slot 9 is the same as the projection contour shape swept by the flap blade 3 in the movement process, and the area of the end wall slot 9 is greater than the projection contour area swept by the flap blade 3 in the movement process, preferably, the area of the end wall slot 9 is 1.05 times the projection contour area swept by the flap blade 3 in the movement process, so as to ensure that the movement of the flap blade 3 will not be hindered by the end wall; the side, away from the cover plate 2, of the end wall 6 is connected with a leading edge fixed blade 7, the leading edge fixed blade 7 is seamlessly connected with the end wall 6; the end face, close to the cover plate 2, of the end wall 6 is provided with an end wall groove 5, a sealing ring 4 is installed in the end wall groove 5, the end wall groove 5 surrounds the end wall slot 9, preferably, the shape of the area surrounded by the end wall groove 5 is consistent with the shape of the end wall slot 9, and the area is 1.1 times the area of the end wall slot 9; the radius of the end wall groove 5 is equal to the radius of the sealing ring 4, and the radius of the sealing ring 4 is equal to the distance between the cover plate 2 and the end wall 6; the area of the cover plate 2 is greater than the area surrounded by the sealing ring 4, and the cover plate 2 always covers the area surrounded by the sealing ring 4 in the movement process of the flap blade 3, preferably, the shape of the cover plate 2 is similar to the projection shape of the area swept by the flap blade 3 in the movement process, and the area of the cover plate 2 is 2 times the area of the end wall slot 9, so as to ensure that the cover plate 2 covers the end wall slot 9 in the whole movement process of the flap blade; the side, close to the connecting assembly 1, of the cover plate 2 is connected with a seal cold gas, and the cover plate is connected with a seal cold gas above the cover plate, the seal cold gas flows into the gap around the cover plate 2 and the flap blade 3, and the pressure of the seal cold gas after passing through the sealing ring 4 is greater than the pressure of the high-temperature gas, so as to reduce the pressure loss when the cold fluid and the hot fluid are mixed, prevent the high-temperature gas from backflowing and reduce the flow loss.

[0049] The working principle of the novel flap type turbine blade structure is as follows:

[0050] Referring to Figures 3 to 5 The rocker arm drives the connecting assembly 1 and drives the cover plate 2 and the flap blade 3 to move, referring to Figure 3 until the position 8 of the flap blade after the rotation is completed. Figure 4 and Figure 5The flap blade 3 moves in the end wall slit 9 according to its movement track, and the cover plate 2 covers the end wall slit 9 during the movement of the flap blade 3, and the leading edge fixed blade 7 and the tip part of the flap blade 3 have no tip gap due to the effects of the sealing ring 4 and the cover plate 2, so that the blade gap leakage vortex is avoided, and the flow loss and total pressure loss in the cascade passage are reduced. The high-temperature gas enters the cascade passage from the turbine inlet, and passes through the leading edge fixed blade 7 and the flap blade 3 successively, and part of the high-temperature gas in the cascade passage leaks from the end wall slit 9, but the leakage of the high-temperature gas can be effectively reduced under the effects of the cover plate 2 and the sealing ring 4, and the sealing cold gas flows into the gap around the cover plate 2 and the gap around the flap blade 3 and the sealing ring 4, so that the purpose of preventing the leakage of the high-temperature gas is achieved, the safe and stable operation of the turbine component is protected, the flow loss in the cascade passage is reduced, and the turbine efficiency is improved.

[0051] The application also provides a variable cycle engine comprising the novel flap type turbine blade structure.

[0052] In summary, the application provides a novel flap type turbine blade structure and a variable cycle engine, the end wall slit 9 is arranged on the end wall 6, the flap blade 3 moves in the end wall slit 9 through the end wall 6, the leading edge fixed blade 7 is seamlessly connected with the end wall 6, the tip part and the bottom part of the leading edge fixed blade and the flap blade have no gap under the joint effects of the cover plate 2 and the sealing ring 4 above the flap blade 3, the generation of the blade gap leakage vortex is effectively avoided, the high-temperature gas leaked from the end wall slit 9 is effectively prevented by the sealing effects of the sealing ring 4 and the sealing cold gas, the safe and stable operation of the turbine component is protected, the flow loss in the cascade passage is reduced, and the turbine efficiency is improved.

[0053] The above only describes the preferred embodiments of the application, and does not use to limit the technical solutions of the application, and those skilled in the art should understand that the technical solutions can be simply modified and replaced without departing from the spirit and principles of the application, and the modified and replaced solutions also belong to the protection scope of the claims.

Claims

1. A flap-type turbine blade structure, characterized by, The application relates to a flap type turbine blade structure which comprises a connecting assembly (1), a cover plate (2), a flap blade (3), an end wall (6) and a leading edge fixed blade (7); one end of the connecting assembly (1) is connected with a rocker arm of an engine, and the other end is sequentially connected with the cover plate (2) and the flap blade (3); the end wall (6) is provided with an end wall slit (9), the flap blade (3) passes through the end wall slit (9) and freely moves in the end wall slit (9); the end wall (6) is provided with a sealing ring (4) on the outer side of the end wall slit (9); the leading edge fixed blade (7) is seamlessly connected with the side of the end wall (6) which is away from the cover plate (2); the side of the cover plate (2) which is close to the connecting assembly (1) is provided with a strict sealing cold gas.

2. The flap-type turbine blade structure according to claim 1, characterized by The shape of the end wall slit (9) is the same as the projection outline shape swept by the flap blade (3) during movement.

3. The flap-type turbine blade structure of claim 2, wherein The area of the end wall slit (9) is larger than the projection outline area swept by the flap blade (3) during movement.

4. The flap-type turbine blade structure of claim 1, wherein The end wall (6) is provided with an end wall groove (5) on the end face of the side which is close to the cover plate (2), and the end wall groove (5) is used for mounting the sealing ring (4).

5. The flap-type turbine blade structure according to claim 4, characterized by The radius of the end wall groove (5) is equal to the radius of the sealing ring (4), and the radius of the sealing ring (4) is equal to the distance between the cover plate (2) and the end wall (6).

6. The flap-type turbine blade structure of claim 1, wherein The side of the end wall (6) which is connected with the leading edge fixed blade (7) is in an I-shaped structure.

7. The flap-type turbine blade structure of claim 1, wherein The area of the cover plate (2) is larger than the area surrounded by the sealing ring (4), and the cover plate (2) always covers the area surrounded by the sealing ring (4) during movement of the flap blade (3).

8. The flap-type turbine blade structure of claim 1, wherein The height of the flap blade (3) is larger than the height of the end wall (6).

9. The flap-type turbine blade structure according to any one of claims 1 to 8, characterized by, The material of the sealing ring (4) is high-temperature-resistant ceramic woven flexible fiber material.

10. A variable cycle engine characterized by, The application further discloses a flap type turbine blade structure. The application further discloses a flap type turbine blade structure.

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