Labyrinth type sealing structure of turbine engine and turbine engine

Abstract

The utility model relates to a labyrinth type sealing structure of a turbine engine, which comprises a rotor and a stator, the rotor and the stator are arranged to be mutually staggered and embedded so as to form a labyrinth type gas flow path between the rotor and the stator, and in the gas flow path, adjacent parts are arranged between the rotor and the stator so as to form a sealing area. In said sealing region, one end of the rotor adjoining the stator comprises a roulette structure comprising flow guide fins arranged to spirally wind threads distributed on an outer circumference of said roulette structure about its central longitudinal axis, such that, when the rotor of the turbine engine rotates, the flow guide fins rotate around the outer circumference of said roulette structure. The flow guide fins generate driving force opposite to the original gas flowing direction on gas flowing in the gas flowing path, and therefore the gas flows in the direction opposite to the direction where the gas leaks out of the turbine engine from the labyrinth type sealing structure. The utility model further relates to a turbine engine comprising the labyrinth type sealing structure.

Description

Technical Field

[0001] The utility model relates to the technical field of aviation engines / turbine engines, in particular to a labyrinth sealing structure of a turbine engine. Background Art

[0002] Aircraft engines, also known as (gas) turbine engines, are a type of rotating machinery that converts the internal energy of high-temperature combustion gas into kinetic energy through rotor components. At present, commonly used rotary sealing structures include contact seals and non-contact seals. Contact seals mainly include expansion ring seals, graphite seals, brush seals, packing seals, etc., and non-contact seals mainly include comb seals, centrifugal seals, impeller seals, etc. Among them, contact seals have small leakage and simple structures, but large friction losses and short lifespans; on the contrary, non-contact seals have large leakage and complex structures, but small friction losses and long lifespans. The sealing method needs to be selected according to actual use requirements.

[0003] In order to ensure the safety and reliability of the engine, there must be a certain gap between the rotating blades and the stationary casing. The existence of the gap makes it inevitable that there will be leakage flow when the engine is working. Such leakage flow causes the gas that should be working in the mainstream area to escape through the gap between the rotor and the stator, resulting in a decrease in the aerodynamic performance of the turbine, and then a decrease in the workability of the entire engine. Therefore, reducing the leakage flow between the rotor and the stator is an important way to improve the performance of aircraft engines / gas turbine engines.

[0004] In order to reduce the leakage flow between the turbine engine rotor and stator, the current existing technology usually adopts the method of reducing the gap between the rotor and stator stages or designing a leakage flow suction device. As for the method of reducing the gap, since the size of the gap changes when the turbine engine works in different working conditions, it is impossible to ensure that the gap is relatively small in all states. At the same time, too small a gap will also cause structural safety risks. As for the leakage flow suction method, the passive suction method cannot quantitatively guarantee the suction effect, and changing to active suction requires an additional set of suction equipment, thereby increasing the overall weight of the engine and failing to meet the weight reduction requirements.

[0005] It should be noted that the information disclosed in the background technology section of the present invention is only intended to increase the understanding of the overall background of the present invention, and should not be regarded as an admission or suggestion in any form that the information constitutes prior art already known to those skilled in the art. Utility Model Content

[0006] Therefore, it is urgent to design a new device for reducing the gap leakage flow between the turbine engine rotor and the stator.

[0007] One of the purposes of the utility model is to provide a labyrinth sealing structure of a turbine engine, the sealing structure comprising a rotor and a stator arranged alternately with each other, wherein the stator is arranged to constitute a fixed casing of the turbine engine and wrap the rotor; the rotor is arranged to rotate around the rotation axis of the turbine engine in the casing constituted by the stator, and is characterized in that the rotor and the stator are arranged to be interlaced with each other to form a labyrinth gas flow path between the rotor and the stator, in which the rotor and the stator have mutually adjacent parts to form a sealing area, in which the end of the stator adjacent to the rotor includes a wear-resistant material. The honeycomb structure comprises a rotor and a stator, wherein one end of the rotor adjacent to the stator comprises a roulette structure, which is arranged to rotate around the rotation axis of the turbine engine in a manner fitting the honeycomb structure of the stator, wherein the roulette structure comprises guide fins, which are arranged to spirally wind around threads distributed on the outer circumference of the roulette structure around its central longitudinal axis, so that when the rotor of the turbine engine rotates, the guide fins generate a driving force opposite to the original gas flow direction for the gas flowing in the gas flow path, thereby causing the gas to flow in a direction opposite to the direction in which the gas leaks out of the turbine engine from the labyrinth sealing structure.

[0008] Therefore, the sealing structure device for turbine engines provided by the utility model adopts a multi-dimensional three-dimensional sealing system constructed by combining a variety of different sealing structures. First, the labyrinth gas flow path formed by the interlaced interlocking between the rotor and the stator constructs a complex multi-level reciprocating flow labyrinth sealing structure as a whole, which can reduce the leakage kinetic energy of the flowing gas step by step, that is, the flow rate of the leakage flow is reduced step by step. In addition, a sealing area is set in the labyrinth gas flow path, and the sealing area uses a physical seal composed of a honeycomb structure and a guide fin, and a pneumatic seal generated by the reverse gas flow formed by the spirally arranged guide fin. As a result, the sealing structure of the utility model obtains a multi-level and multi-dimensional sealing effect formed by an organic combination of a labyrinth path seal, a physical seal and a pneumatic seal. Moreover, such a combination is obtained by improving the internal structure of the existing turbine engine, and does not require the addition of additional accessories or devices, so that the cost and weight of the turbine engine can be effectively controlled.

[0009] It should be understood that the so-called "labyrinth seal" or labyrinth seal refers to a sealing method with many tortuous chambers between the rotating parts and the fixed parts, thereby reducing leakage.

[0010] It should be understood that the so-called "interlaced interlocking" means that multiple rotors and stators are combined with each other in a cross-nested manner in a complementary shape, so that each rotor is located between two adjacent stators, and through their complementary shapes, each rotor and the adjacent stator are adjacent to each other without affecting the relative rotation between them.

[0011] It should be understood that the so-called "gas flow path" refers to the space (chamber) formed by the gaps between a plurality of staggered rotors and stators, and these spaces are interconnected to form the flow path of the gas therein.

[0012] According to a preferred embodiment of the utility model, the central longitudinal axis of the wheel-disk structure is parallel to the rotation axis of the turbine engine, and the threads of the guide fins are arranged obliquely relative to the central longitudinal axis of the wheel-disk structure in a manner that is not perpendicular to the rotation axis. The inclination angle of the threads of the guide fins can be adjusted according to actual design requirements, so that when the rotor rotates, the reverse driving force generated by the threads of the guide fins is greater than or equal to the flow force of the leakage flow in the gas flow path in the original leakage direction, so that the gas flows in the direction opposite to the direction of leakage out of the turbine engine.

[0013] According to a preferred embodiment of the utility model, the threads of the guide fins are not parallel to each other, so that a complex vortex structure can be formed around the guide fins, and the complex vortex structure can inhibit the flow of air in the gap between the guide fins and the honeycomb structure, thereby producing a pneumatic sealing effect and further inhibiting the passage of leakage flow.

[0014] According to a preferred embodiment of the utility model, the wheel-disk structure includes a first-stage cylinder and a second-stage cylinder which are roughly cylindrical, the first-stage cylinder and the second-stage cylinder are concentric and arranged with a common center axis, the center axis is the central longitudinal axis of the wheel-disk structure, and the diameter of the first-stage cylinder is greater than the diameter of the second-stage cylinder, wherein the guide fins are arranged on the second-stage cylinder.

[0015] According to a preferred embodiment of the utility model, the stator also includes a nozzle, which is arranged above the honeycomb structure of the stator and adjacent to the disc structure of the rotor, so that the gas flow reversed by the guide fins flows back to the front of the nozzle, thereby increasing the gas pressure in front of the nozzle, thereby preventing the high-temperature gas in the gas flow path flowing in the direction of leaking out of the turbine engine from the labyrinth sealing structure from entering the nozzle.

[0016] According to a preferred embodiment of the utility model, the labyrinth sealing structure also includes a secondary air cooling system, which is configured to deliver cooling gas to the gas flow path to reduce the temperature of the high-temperature gas flowing in the gas flow path, and the cooling gas delivered by the secondary air cooling system is delivered into the gas flow path along a flow direction opposite to that of the high-temperature gas flowing in the gas flow path.

[0017] The utility model also relates to a turbine engine, characterized in that it comprises the above-mentioned labyrinth sealing structure of the turbine engine.

[0018] It should be understood that the above general description and the following detailed description are only exemplary and explanatory and cannot limit the present invention. Other features, purposes and advantages of the present invention will become apparent from the specification, drawings and claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for the description of the embodiments. It is easy for those skilled in the art to understand that these drawings are only used for illustrative purposes and are not intended to limit the scope of protection of the present invention. For the purpose of illustration, these drawings may not be drawn completely to scale.

[0020] Figure 1 A schematic cross-sectional view of a labyrinth sealing structure of a turbine engine according to an embodiment of the utility model is shown.

[0021] Figure 2 Shows Figure 1 A side view of the middle wheel disc structure 21 showing specific details.

[0022] Figure 3 A schematic diagram of gas flow inside a turbine engine in the prior art is shown.

[0023] Figure 4 According to an embodiment of the utility model, the following is arranged: Figure 2 A schematic diagram of the aerodynamic flow inside the turbine engine behind the guide fins 22 is shown.

[0024] Figure 5 A partial schematic diagram of a labyrinth sealing structure according to a more preferred embodiment of the utility model is shown. DETAILED DESCRIPTION

[0025] Here, exemplary embodiments will be described in detail, examples of which are shown in the accompanying drawings. When the following description refers to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments according to the utility model. Instead, they are only examples of devices consistent with some aspects of the utility model as detailed in the attached claims.

[0026] Figure 1 A cross-sectional schematic diagram of a labyrinth seal structure of a turbine engine according to an embodiment of the utility model is shown, wherein the left side of the figure shows a part of the turbine engine as a whole, and the right side shows an enlarged view of the red box area in the left side figure.

[0027] like Figure 1 As shown in FIG. 1 , the sealing structure of the turbine engine includes a plurality of rotors 2 (green part) and stators 3 (purple part) arranged alternately with each other. The stators 3 are arranged to form a fixed casing of the turbine engine and wrap the rotors 2. The rotors 2 are arranged to rotate around the rotation axis 1 of the turbine engine in the casing formed by the stators 3. Figure 1 As shown, the rotor 2 and the stator 3 are arranged to be interlaced with each other to form a labyrinth-like gas flow path 4 between the rotor 2 and the stator 3 (the black arrow shows the flow direction of the leakage flow gas). In the gas flow path 4, there are mutually adjacent parts between the rotor 2 and the stator 3 to form a sealing area 5, in which the end of the stator 3 adjacent to the rotor 2 includes a honeycomb structure 31 made of wear-resistant material, and the end of the rotor 2 adjacent to the stator 3 includes a wheel disc structure 21, which is arranged to rotate around the rotation axis 1 of the turbine engine in a manner that fits the honeycomb structure 31 of the stator.

[0028] Figure 2 Shows Figure 1 A side view of the details of the middle wheel disc structure 21. Figure 2 As shown, the roulette structure 21 includes a first-stage cylinder 211 and a second-stage cylinder 212 which are roughly cylindrical. The first-stage cylinder 211 and the second-stage cylinder 212 are concentric and share a central axis, and the central axis is the central longitudinal axis 213 of the roulette structure 21. As shown in the figure, the diameter of the first-stage cylinder 211 is greater than the diameter of the second-stage cylinder 212. The second-stage cylinder 212 is provided with a guide fin 22 (purple area in the figure), and the guide fin 22 is arranged to be spirally wound around the threads distributed on the outer circumference of the second-stage cylinder 212 around its central longitudinal axis 213.

[0029] Preferably, the central longitudinal axis 213 of the disk structure 21 is parallel to the rotation axis 1 of the turbine engine, and the threads of the guide fins 22 are arranged obliquely relative to the central longitudinal axis 213 of the disk structure 21 in a non-perpendicular manner to the rotation axis 1 of the turbine engine.

[0030] Preferably, the threads of the guide fins 22 are not parallel to each other.

[0031] Thus, when the turbine engine rotor 2 rotates, the guide fins 22 cause the gas flowing in the gas flow path 4 to have a direction different from the original gas flow direction ( Figure 1 The driving force is opposite to the direction of the black arrow in the middle, so that the gas flows in the opposite direction to the direction of leakage from the turbine engine from the labyrinth seal structure. See the following reference for details. Figure 3 and Figure 4 Description.

[0032] Figure 3 and Figure 4 The flow direction of the gas in the turbine engine before and after the guide fins 22 of the present invention are provided are shown in a comparative manner. Figure 3 It is a schematic diagram of the original flow direction of the gas in the turbine engine when the guide fins 22 of the present invention are not provided; Figure 4 It is a schematic diagram of the gas flow in the turbine engine with the flow direction reversed after the guide fins 22 of the present invention are provided.

[0033] Figure 3 The figure shows a schematic diagram of gas flow inside a turbine engine in the prior art, wherein the green part is the rotor 2 and the purple part is the stator 3. In the prior art, when the rotor 2 rotates in the fixed casing formed by the stator 3, the flow direction of the gas in the flow path 4 formed by the gap space between the rotor 2 and the stator 3 is as shown by the blue arrow F in the figure, i.e., the direction of gas leakage out of the turbine engine from the labyrinth seal structure.

[0034] Figure 4 According to an embodiment of the utility model, the following is arranged: Figure 2 Schematic diagram of aerodynamic flow inside a turbine engine behind the guide fin 22 shown. Thanks to the spirally inclined guide fins 22 arranged on the rotor disc structure 21, the reverse driving force generated by the threads of the guide fins 22 when the rotor rotates is greater than or equal to the flow force of the leakage flow in the original leakage direction in the gas flow path, so that the gas flows in the direction R opposite to the direction F of leakage out of the turbine engine. Thereby, the risk of airflow leaking out from the gap between the turbine engine rotor and the stator is effectively curbed.

[0035] Preferably, the pneumatic sealing effect can be further enhanced by adjusting the inclination angle of the threads of the guide fins 22 and increasing the staggered angles of the threads that are not parallel to each other. The spiral shape can push the gas in the most appropriate direction according to the design selection, just like a pump or impeller in the air.

[0036] Figure 5 FIG. 2 shows a partial schematic diagram of a labyrinth seal structure according to a more preferred embodiment of the present utility model. Figure 5 As shown, the stator 3 further includes a nozzle 32, which is arranged above the honeycomb structure 31 of the stator and adjacent to the wheel disc structure 21 of the rotor 2. In this way, the gas flow R reversed by the guide fins 22 flows back to the front of the nozzle 32, thereby increasing the gas pressure in front of the nozzle 32, thereby preventing the high-temperature gas in the gas flow path flowing in the direction F of leaking out of the turbine engine from the labyrinth sealing structure from entering the nozzle 32.

[0037] In addition, in this embodiment, the labyrinth sealing structure also includes a secondary air cooling system 6, which is configured to deliver cooling gas (blue arrow S) to the gas flow path 4 to reduce the temperature of the high-temperature gas (red arrow F) flowing in the original gas flow path. At the same time, the cooling gas delivered by the secondary air cooling system 6 is delivered into the gas flow path 4 along the flow direction S opposite to the high-temperature gas flowing in the original gas flow path, and merges with the gas flow R reversed by the guide fins 22 in front of the nozzle 32, thereby forming a more powerful reverse airflow W to counter the high-temperature gas (red arrow F, the high-temperature gas constitutes the source of the leakage flow) flowing in the original gas flow path. Since the mixed reverse airflow W (including the cooling gas delivered by the secondary air cooling system 6 and the gas flow reversed by the guide fins 22, both in the same direction) is opposite to the direction of the high-temperature gas flowing in the original gas flow path, and the temperature is lower, it can well suppress the flow of the high-temperature gas in the original direction, reduce the intensity and energy of the leakage flow, and form a more effective pneumatic sealing effect.

[0038] Unless otherwise defined, the technical and scientific terms used herein have the same meanings as those generally understood by those skilled in the art of the technical field of the present invention. The terms used in this application are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The singular forms of "a", "an" and "the" used in this application are also intended to include plural forms, unless the context clearly indicates other meanings. It should also be understood that the term "and / or" that may be used herein refers to and includes any or all possible combinations of one or more associated listed items.

[0039] Terms such as "upper", "lower", "left", "right", "front", "back", "thickness", "length", "width" and the like that may be used herein to indicate relative positions in space are for the purpose of convenience of description to describe the relationship of one feature relative to another feature as shown in the accompanying drawings, and are not limited to one position or one spatial orientation. It is understood that, depending on the placement of the product, the terms of relative positions in space may be intended to include different orientations in addition to the orientation shown in the drawings, and should not be understood as limiting. Words such as "include" or "comprise" and the like used herein mean that the elements or objects appearing before "include" or "comprises" include the elements or objects listed after "include" or "comprises" and their equivalents, and do not exclude other elements or objects.

[0040] It should be understood that the terms “first”, “second” and similar terms used in the present application specification do not indicate any order, quantity or importance, but are only used to distinguish different components.

[0041] The above are only preferred implementation modes of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention shall be included in the scope of protection of the present invention.

Claims

1. A labyrinth seal structure of a turbine engine, the seal structure comprising a rotor and a stator arranged alternately with each other, wherein: The stator is arranged to constitute a fixed casing of the turbine engine and to enclose the rotor; The rotor is arranged to rotate around the rotation axis of the turbine engine in a casing formed by a stator, and is characterized in that the rotor and the stator are arranged to be interlaced and interlocked with each other to form a labyrinth-like gas flow path between the rotor and the stator, in which the rotor and the stator have mutually adjacent parts to form a sealing area, in which the end adjacent to the stator and the rotor includes a honeycomb structure formed of wear-resistant material; the end adjacent to the stator includes a roulette structure, which is arranged to rotate around the rotation axis of the turbine engine in a manner that fits the honeycomb structure of the stator, wherein the roulette structure includes guide fins, which are arranged to spirally wind around threads distributed on the outer circumference of the roulette structure around its central longitudinal axis, so that when the rotor of the turbine engine rotates, the guide fins generate a driving force opposite to the original gas flow direction for the gas flowing in the gas flow path, thereby causing the gas to flow in a direction opposite to the direction of leakage from the turbine engine from the labyrinth-like sealing structure.

2. The labyrinth seal structure of a turbine engine according to claim 1, characterized in that: The central longitudinal axis of the disk-like structure is parallel to the rotation axis of the turbine engine, and the threads of the guide fins are arranged obliquely relative to the central longitudinal axis of the disk-like structure in a manner not perpendicular to the rotation axis.

3. The labyrinth seal structure of a turbine engine according to claim 1 or 2, characterized in that: The threads of the guide fins are not parallel to each other.

4. The labyrinth seal structure of a turbine engine according to claim 1 or 2, wherein: The wheel-disk structure includes a first-stage cylinder and a second-stage cylinder which are roughly cylindrical. The first-stage cylinder and the second-stage cylinder are concentric and share a common central axis. The central axis is the central longitudinal axis of the wheel-disk structure, and the diameter of the first-stage cylinder is greater than the diameter of the second-stage cylinder, wherein the guide fins are arranged on the second-stage cylinder.

5. The labyrinth seal structure of a turbine engine according to claim 1 or 2, wherein: The stator also includes a nozzle, which is arranged above the honeycomb structure of the stator and adjacent to the disc structure of the rotor, so that the gas flow reversed by the guide fins flows back to the front of the nozzle, thereby increasing the gas pressure in front of the nozzle, thereby preventing the high-temperature gas in the gas flow path flowing in the direction of leaking out of the turbine engine from the labyrinth sealing structure from entering the nozzle.

6. The labyrinth seal structure of a turbine engine according to claim 1 or 2, wherein: The labyrinth sealing structure also includes a secondary air cooling system, which is configured to deliver cooling gas to the gas flow path to reduce the temperature of the high-temperature gas flowing in the gas flow path. The cooling gas delivered by the secondary air cooling system is delivered into the gas flow path along a flow direction opposite to that of the high-temperature gas flowing in the gas flow path.

7. A turbine engine, characterized in that: It comprises a labyrinth seal structure for a turbine engine as claimed in any one of the preceding claims.

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