A stepped serration multi-blow jet narrow tail structure

Abstract

The utility model discloses a kind of stepped gill tooth multi-bleeding air jet narrow tail structures, static vane casing, crown static vane, sealing bush are sequentially arranged along the radial outer side to the inner side of rotor and mutually fixed, moving vane casing is fixed with static vane casing;Gill tooth sealing main part is set on the outer periphery of rotor and rotates integrally with rotor;Sealing bush, gill tooth sealing main part are set in the containing groove of rotor, along the direction of static vane casing to moving vane casing, the outer surface of gill tooth sealing main part is provided with multiple gill teeth of gradually reducing height, sealing bush is correspondingly provided with a section of stepped and the inner surface with the clearance of gill tooth;The bottom surface between the end wall of crown static vane and sealing bush is provided with cavity, the inner surface of sealing bush stepped is communicated with cavity, and the end wall of crown static vane is provided with multiple jet holes that communicate cavity and angle region.Jet hole is suppressed through gill tooth to reduce the leakage flow speed of compressor stage, and leakage flow is intercepted in gill tooth sealing structure, and angle region low-energy fluid accumulation is inhibited.

Description

Technical Field

[0001] This utility model relates to the technical field of aero-engine compressors, and in particular to a stepped-shaped comb-tooth multi-air jet narrow tail structure. Background Technology

[0002] As a crucial component of aero-engines, the performance of the compressor significantly impacts the overall thermal efficiency and stability of the engine. With increasing compressor load, its internal flow field structure becomes increasingly complex. Studies have shown that interstage leakage in the compressor worsens the internal flow field structure, degrades the compressor's flow capacity, reduces efficiency, and is accompanied by compressor surge.

[0003] For example, in the prior art, there is a Chinese utility model patent with application number CN201920122970.7, entitled "A Rotatable Inner End Wall Casing for a Compressor Rotor." It includes: a moving impeller disk, a moving blade casing, a stationary impeller disk, a stationary blade casing, and a rotatable inner end wall. The moving impeller disk has moving blades, and the stationary impeller disk has stationary blades. A rotating shaft passage is provided at the axis of the moving and stationary impeller disks, and a rotating shaft is provided within the rotating shaft passage. The moving blade casing has a rotatable inner end wall. The rotatable inner end wall facilitates the flow of low-energy fluid accumulated in the casing end wall region. Although the flow of low-energy fluid accumulated in the casing end wall region is considered, the impact of interstage leakage flow in the low-compressor is not taken into account.

[0004] Therefore, how to reduce the impact of interstage leakage flow in the compressor and make the most of the leakage flow has become an urgent problem to be solved. Utility Model Content

[0005] The purpose of this invention is to provide a toothed sealing air jet structure that can reuse the interstage leakage flow of a compressor, thereby solving the problem that the interstage leakage flow deteriorates the internal flow field structure of the compressor and reduces the compressor efficiency.

[0006] To achieve the above objectives, this utility model provides the following technical solution:

[0007] A stepped-shaped grating tooth multi-air jet narrow tail structure includes a moving blade, a moving blade casing, a rotor, a crowned stationary blade, a stationary blade casing, a sealing bushing, and a grating tooth sealing body;

[0008] The moving blade is fixed to the outer periphery of the rotor;

[0009] The stationary blade casing, the crowned stationary blade, and the sealing bushing are arranged sequentially from the outer to the inner side of the rotor and fixed to each other. The moving blade casing is fixedly connected to the stationary blade casing.

[0010] The main body of the comb seal is set on the outer periphery of the rotor and rotates integrally with the rotor;

[0011] The sealing bushing and the grate sealing body are arranged in the receiving groove of the rotor. Along the direction from the stationary blade casing to the moving blade casing, the outer surface of the grate sealing body is provided with multiple rings of grate teeth arranged at intervals and with gradually decreasing height. The sealing bushing is correspondingly provided with a stepped inner surface with gaps between it and the grate teeth.

[0012] A cavity is provided between the end wall of the crowned vane and the sealing bushing. The stepped inner surface of the sealing bushing is connected to the cavity. The inner wall of the end wall of the crowned vane is provided with multiple jet holes that are respectively connected to the cavity and the suction surface, pressure surface, and outer surface of the end wall of the crowned vane.

[0013] Furthermore, the crowned vane and the sealing bushing are fixedly connected by a tenon and groove structure. The crowned vane is a split structure and is divided into multiple crowned vane units arranged in a circumferential array.

[0014] The inner wall surface of the crowned leaf unit is provided with an isosceles trapezoidal protrusion, the side of the protrusion facing the sealing bushing is wider than the side away from the sealing bushing; a trapezoidal groove matching the protrusion is formed on the outer periphery of the sealing bushing, the protrusion and the trapezoidal groove form the tenon and groove structure.

[0015] The sealing bushing has a cavity set at the bottom of the trapezoidal groove.

[0016] Furthermore, the grate sealing body and the rotor are fixedly connected by a tenon and groove structure; the axial sides of the grate sealing body are provided with protrusions to widen the inner wall surface of the grate sealing body, and the two groove walls of the corresponding receiving groove are provided with mounting grooves that match the protrusions.

[0017] Furthermore, along the direction from the stationary blade casing to the moving blade casing, the diameter of the jet orifice gradually decreases.

[0018] Furthermore, the stepped inner surface of the sealing bushing has multiple drainage holes for communicating with the cavity and whose positions correspond to the crowned stationary vane units. The number of drainage holes is the same as the number of crowned stationary vane units, and the drainage holes are located between the two highest rings of grates on the grating sealing body.

[0019] In the above technical solution, the stepped comb-shaped multi-air-jet narrow-tail structure of this utility model has the following beneficial effects:

[0020] By incorporating a grate-shaped sealing body with stepped grates, the leakage flow velocity between compressor stages is reduced, and the leakage flow is intercepted within the grate-shaped sealing body. If leakage flow crosses the grates, multiple jet holes are opened on the suction surface, pressure surface, and endwall, allowing the leakage flow to be blown out to the corner region through these holes, suppressing the accumulation of low-energy fluid in the corner region. The combination of the grate-shaped sealing body and the jet holes delays the onset of corner separation, thereby improving the flow field structure within the compressor channel, enhancing the compressor's flow capacity, reducing flow losses caused by corner separation, and improving the compressor's diffusion capacity. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this utility model. For those skilled in the art, other drawings can be obtained based on these drawings.

[0022] Figure 1 A schematic diagram of the planar structure of the stepped comb-shaped multi-air jet narrow tail structure provided by this utility model;

[0023] Figure 2 A three-dimensional structural schematic diagram of the stepped comb-shaped multi-air jet narrow tail structure provided by this utility model;

[0024] Figure 3 A schematic diagram of the structure of the comb seal body and rotor assembly provided by this utility model;

[0025] Figure 4 A schematic diagram of the structure of the moving blade provided by this utility model;

[0026] Figure 5 A schematic diagram of the structure of the sealing bushing and crowned stationary blade assembly provided by this utility model;

[0027] Figure 6 This is a schematic diagram of the structure of the crowned still leaf unit provided by this utility model.

[0028] In the diagram: 1. Moving blade casing; 2. Stationary blade casing; 3. Rotor; 31. Receiving groove; 4. Crowned stationary blade; 5. Moving blade; 6. Sealing bushing; 61. Drainage hole; 7. Grate sealing body; 8. Jet hole. Detailed Implementation

[0029] To enable those skilled in the art to better understand the technical solution of this utility model, the present utility model will be further described in detail below with reference to the accompanying drawings.

[0030] It should be noted that the terms "above," "one end," "up," etc. used in this document indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description. Similar expressions are only for illustrative purposes and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model. In addition, the terms "part," "two parts," etc. are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0031] like Figure 1-6 The stepped-shaped grating tooth multi-air jet narrow tail structure shown includes a moving blade 5, a moving blade casing 1, a rotor 3, a crowned stationary blade 4, a stationary blade casing 2, a sealing bushing 6, and a grating tooth sealing body 7. Figure 1-5 The rotor shown in the figure has only its outer casing. With the rotor axis as the front-to-back direction, the moving blade casing 1 side is the rear and the stationary blade casing 2 side is the front.

[0032] Among them, the moving blade 5 is fixed on the outer periphery of the rotor 3; the moving blade is fixed on the rotor and rotates with the rotation of the rotor.

[0033] The stationary blade casing 2, the crowned stationary blade 4, and the sealing bushing 6 are arranged sequentially from the outer to the inner radial side of the rotor 3 and fixed to each other. The moving blade casing 1 is fixedly connected to the stationary blade casing 2. The crowned stationary blade 4 is fixed to the stationary blade casing 2 and does not rotate with the rotor. The sealing bushing 6 is installed on the crowned stationary blade 4 and does not rotate with the rotor 3. The stationary blade casing, the crowned stationary blade, and the sealing bushing are installed together and do not rotate. The stationary blade casing 2 and the moving blade casing 1 are installed outside the rotor 3.

[0034] The grate sealing body 7 is disposed on the outer periphery of the rotor 3 and rotates integrally with the rotor 3; the grate sealing body 7 is installed on the rotor 3 and rotates with the rotor.

[0035] The sealing bushing 6 and the grate sealing body 7 are disposed in the receiving groove 31 of the rotor 3, with the sealing bushing 6 located outside the grate sealing body 7. Along the direction from the stationary blade casing 2 to the moving blade casing 1, the outer surface of the grate sealing body 7 is provided with multiple rings of grate teeth with gradually decreasing heights, and the sealing bushing 6 correspondingly has a stepped inner surface with gaps between it and the grate teeth. Figure 1 The axial middle portion of the grate-shaped sealing body 7 shown has four, four rings of grates, with a gap between the four grates. The axial middle portion of the inner wall of the sealing bushing 6 is stepped, and a gap needs to be left between the inner wall of the stepped portion and the grates. To avoid friction, the gap is generally 0.2-0.5mm.

[0036] A cavity is formed between the end wall of the crowned vane 4, the side of the crowned vane 4 facing the sealing bushing 6, and the sealing bushing 6. The crowned vane 4 and the sealing bushing 6 are preferably made of the same material. The sealing bushing 6 facilitates the machining of the cavity. The stepped inner surface of the sealing bushing 6 communicates with the cavity. The end wall of the crowned vane 4 has multiple jet holes that connect the cavity to the suction surface, pressure surface, and outer surface of the end wall, respectively. That is, the jet holes 8 are inclined relative to the rotor's axial direction, and the multiple jet holes 8 are not required to be arranged in parallel. The jet holes 8 penetrate the end wall, or penetrate from the inner wall surface of the end wall to the suction surface of the crowned vane 4, or penetrate from the inner wall surface of the end wall to the pressure surface of the crowned vane 4. The inlet of the jet holes 8 is through the cavity, and the outlet is in different places: the end wall, the suction surface, and the pressure surface. The suction surface is the convex surface of the blade, and the pressure surface is the concave surface of the blade.

[0037] In existing technologies, leakage flow primarily occurs from front to back, passing through the two opposing walls (front and rear) of the receiving groove 31. The leakage flow first enters the bottom of the receiving groove 31 through the gap between the crowned vane 4 and the front groove wall, and finally passes through the gap between the crowned vane 4 and the rear groove wall, flowing from the high-pressure area to the low-pressure area. This new design incorporates a sealing bushing 6 and a grate-shaped sealing body 7 within the receiving groove 31. The grate height of the grate-shaped sealing body 7 gradually decreases, forming a stepped grate, which reduces the interstage leakage flow velocity in the compressor and intercepts the leakage flow within the gaps and spaces between adjacent grate teeth. Furthermore, if leakage flow crosses the grate structure, multiple jet holes 8 are opened on the suction surface, pressure surface, and end wall of the crowned vane 4. The corner region typically refers to the area formed by the angle between the suction surface and the end wall, where separation vortices mainly exist. Preferably, the diameter of the jet orifice gradually decreases from the front end to the rear end. This convergent structure accelerates the leakage flow, allowing it to be rapidly ejected into the corner region, thus suppressing the accumulation of low-energy fluid in the corner. Through these innovative improvements, the starting point of corner separation is delayed, thereby improving the flow field structure within the compressor channel, enhancing the compressor's flow capacity, reducing flow losses caused by corner separation, and increasing the compressor's diffusion capacity.

[0038] By changing the height of the grate teeth, increasing the number of jet holes, and changing the opening position of the jet holes, an end-shrinkage structure is formed, which reuses the interstage leakage flow of the compressor and further improves the compressor performance.

[0039] In a preferred embodiment, the crowned vane 4 and the sealing bushing 6 are fixedly engaged via a tenon-and-groove structure. The crowned vane 4 is a split structure divided into multiple crowned vane units arranged in a circumferential array. Each crowned vane unit includes an end wall and blades. The end wall is generally strip-shaped, and the blades are fixed to the outer circumferential surface of the end wall. The tip of each blade has a strip-shaped structure opposite to the end wall, and this strip-shaped structure is fixed to the vane housing 2. Figure 5-6 As shown, where Figure 5Part of the crowned still leaf unit is hidden.

[0040] The inner wall surface of the crowned vane unit has an isosceles trapezoidal protrusion located in the axial middle portion of the inner wall surface. The side of the protrusion facing the sealing bushing 6 is wider than the side away from the sealing bushing 6; a ring of trapezoidal grooves matching the protrusions is formed on the outer periphery of the sealing bushing 6, and the protrusions and trapezoidal grooves form a mortise and tenon structure. The crowned vane 4 is a separate structure to facilitate the installation of the crowned vane unit onto the sealing bushing 6 via the mortise and tenon structure.

[0041] The sealing bushing 6 has a cavity set at the bottom of the trapezoidal groove.

[0042] More specifically, the stepped inner surface of the sealing bushing 6 has drainage holes 61 that connect to the cavity and are located corresponding to the crowned vane unit. The number of drainage holes 61 is the same as the number of crowned vane units, and the drainage holes 61 are located between the two highest grates of the grate sealing body 7. The leakage flow passes between the two highest grates of the grate sealing body 7, and part of the airflow will reach the cavity through the drainage holes 61. The cavity acts like a pressure equalization chamber, and then reaches the corner area through the jet holes 8.

[0043] In a preferred embodiment, the toothed sealing body 7 and the rotor 3 are fixedly engaged via a tenon and groove structure; the toothed sealing body 7 has protrusions on both axial sides to widen the inner wall surface of the toothed sealing body 7, and the toothed sealing body 7 is an inverted T-shape with a wider radial inner side. The two groove walls of the corresponding receiving groove 31 are provided with mounting grooves that match the protrusions.

[0044] In a preferred embodiment, the diameter of the jet orifice 8 gradually tapers along the direction from the stationary blade casing 2 to the moving blade casing 1. This accelerates the leakage flow, allowing it to be rapidly ejected through the jet orifice into the corner area.

[0045] The foregoing description only illustrates certain exemplary embodiments of the present invention. Undoubtedly, those skilled in the art can modify the described embodiments in various ways without departing from the spirit and scope of the present invention. Therefore, the above drawings and descriptions are illustrative in nature and should not be construed as limiting the scope of protection of the claims of the present invention.

Claims

1. A stepped-shaped comb-like multi-air-jet narrow-tail structure, characterized in that, Includes moving blade (5), moving blade casing (1), rotor (3), crowned stationary blade (4), stationary blade casing (2), sealing bushing (6), and toothed sealing body (7); The moving blade (5) is fixed on the outer periphery of the rotor (3); The stationary blade casing (2), the crowned stationary blade (4), and the sealing bushing (6) are arranged sequentially from the outer side to the inner side of the rotor (3) and fixed to each other. The moving blade casing (1) is fixedly connected to the stationary blade casing (2). The toothed sealing body (7) is set on the outer periphery of the rotor (3) and rotates integrally with the rotor (3); The sealing bushing (6) and the toothed sealing body (7) are arranged in the receiving groove (31) of the rotor (3). Along the direction from the stationary blade casing (2) to the moving blade casing (1), the outer surface of the toothed sealing body (7) is provided with multiple rings of toothed teeth arranged at intervals and with gradually decreasing height. The sealing bushing (6) is provided with a stepped inner surface with gaps between it and the toothed teeth. A cavity is provided between the end wall of the crowned vane (4) and the sealing bushing (6). The stepped inner surface of the sealing bushing (6) is connected to the cavity. The inner wall of the end wall of the crowned vane (4) is provided with a plurality of jet holes (8) that are respectively connected to the suction surface, pressure surface and outer surface of the end wall of the crowned vane (4) of the cavity.

2. The stepped comb-shaped multi-air jet narrow tail structure according to claim 1, characterized in that, The crowned vane (4) and the sealing bushing (6) are fixedly connected by a tenon and groove structure. The crowned vane (4) is a split structure and is divided into multiple crowned vane units arranged in a circumferential array. The inner wall surface of the crowned leaf unit is provided with an isosceles trapezoidal protrusion, the side of the protrusion facing the sealing bushing (6) is wider than the side away from the sealing bushing (6); a trapezoidal groove matching the protrusion is formed on the outer periphery of the sealing bushing (6), the protrusion and the trapezoidal groove form the tenon and groove structure. The sealing bushing (6) has the cavity set at the bottom of the trapezoidal groove.

3. The stepped comb-shaped multi-air jet narrow tail structure according to claim 1, characterized in that, The toothed sealing body (7) and the rotor (3) are fixedly connected by a tenon and groove structure; the toothed sealing body (7) has protrusions on both axial sides to widen the inner wall of the toothed sealing body (7), and the corresponding receiving groove (31) has mounting grooves that match the protrusions on the two groove walls.

4. The stepped comb-shaped multi-air jet narrow tail structure according to claim 1, characterized in that, Along the direction from the stationary blade casing (2) to the moving blade casing (1), the diameter of the jet hole (8) gradually decreases.

5. The stepped comb-shaped multi-air jet narrow tail structure according to claim 2, characterized in that, The stepped inner surface of the sealing bushing (6) has multiple drainage holes (61) for communicating with the cavity and whose positions correspond to the crowned stationary vane unit. The number of drainage holes (61) is the same as the number of crowned stationary vane units. The drainage holes (61) are located between the two highest rings of grates on the grating sealing body (7).

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