Gas turbine stator assembly and gas turbine

Abstract

The invention discloses a gas turbine stator assembly and a gas turbine, relates to the technical field of gas turbines, and aims to solve the problem that a turbine stator structure deforms due to temperature stress, so that the strength is reduced. The gas turbine stator assembly comprises a turbine case, a plurality of turbine stator blades and a turbine stator disc, one ends of the multiple turbine stator blades are fixedly connected to the interior of the turbine case, and the multiple turbine stator blades extend in the radial direction of the turbine case from the inner circumferential face of the turbine case; the turbine static disc is in a disc shape, a through hole is formed in the center of the disc face of the turbine static disc and used for allowing a rotating shaft to penetrate through, the turbine static blades are fixedly connected to the peripheral face of the turbine static disc, an annular groove is formed in the disc face, facing the turbine movable disc of the same stage, of the turbine static disc, and the annular groove and the disc face of the turbine static disc are concentrically formed. The gas turbine comprises the gas turbine stator assembly of the technical scheme. The gas turbine stator assembly provided by the invention is used for weakening the influence of deformation of the turbine stator structure caused by temperature stress on the strength of the turbine stator structure.

Description

Technical Field

[0001] The present invention relates to the technical field of gas turbines, and in particular to a gas turbine stator assembly and a gas turbine. Background Art

[0002] The new generation of cryogenic liquid rocket regenerative cycle engines generally use high-temperature, high-pressure, oxygen-rich gas to drive the turbine. Due to its inherent characteristics, the turbine components are arranged alternately in the form of rotors and stators. After the high-temperature, high-pressure, oxygen-rich gas is expanded and accelerated by the turbine stator, it drives the turbine blades to rotate at high speed to output power. In a certain type of high-thrust regenerative cycle engine turbine oxygen pump, the cryogenic liquid oxygen flowing out of the cryogenic oxygen pump and the high-temperature gas act together on the turbine stator structure. The huge temperature difference between the high-temperature gas and the cryogenic liquid oxygen requires the turbine stator to withstand greater temperature stress. This causes the turbine stator structure to deform, resulting in a reduction in the strength of the turbine stator structure and damages the performance of the turbine. Summary of the invention

[0003] The object of the present invention is to provide a gas turbine stator assembly and a gas turbine, which are used to reduce the deformation of the turbine stator structure caused by temperature stress and avoid the reduction of strength caused by the deformation of the structure.

[0004] In order to achieve the above object, the present invention provides the following technical solutions:

[0005] A gas turbine stator assembly, comprising:

[0006] turbine casing;

[0007] A plurality of turbine stator blades, one end of which is fixedly connected to the inside of the turbine casing and extends from the inner circumference of the turbine casing to the radial direction of the turbine casing;

[0008] The turbine stator is in the shape of a disc, and a through hole is provided in the center of the disc surface of the turbine stator, and the through hole is used to pass through the turbine moving disc. The other end of the turbine stator blade is fixedly connected to the outer peripheral surface of the turbine stator, and an annular groove is provided on the disc surface of the turbine stator facing the same-level turbine moving disc, and the annular groove is provided concentrically with the disc surface of the turbine stator.

[0009] Optionally, in the above-mentioned gas turbine stator assembly, the radial distance between the groove edge of the annular groove away from the center of the turbine stator disk and the edge of the outer peripheral surface of the turbine stator disk is B, and B is 3mm-5mm larger than the blade thickness of the turbine stator blade at the contact point with the turbine stator disk.

[0010] Optionally, in the above-mentioned gas turbine stator assembly, the axial depth of the annular groove is 1 / 4-1 / 3 of the axial length of the turbine stator blade grid composed of a plurality of turbine stator blades.

[0011] Optionally, in the above-mentioned gas turbine stator assembly, a concave cavity is opened along the inner circumference of the turbine stator disk, and the concave cavity is opened in the turbine stator disk along the inner circumference of the turbine stator disk radially away from the turbine moving disk. The gas turbine stator assembly is also provided with an annular boss, which is opened on the disk surface of the turbine stator disk facing the turbine moving disk of the same level. The annular boss is concentrically arranged with the disk surface of the turbine stator disk, and the axial surface of the annular boss is penetrated by the axial extension surface of the axial surface of the concave cavity where the edge of the axial surface of the concave cavity is radially away from the turbine moving disk.

[0012] Optionally, in the above-mentioned gas turbine stator assembly, the axial height of the annular boss is 1.5 mm-4 mm.

[0013] Optionally, in the above-mentioned gas turbine stator assembly, the side wall surface of the annular boss away from the center of the disk surface is the groove wall surface of the annular groove close to the center of the disk surface.

[0014] Optionally, in the above-mentioned gas turbine stator assembly, the turbine stator blades are electron beam welded to the turbine casing.

[0015] Optionally, in the above-mentioned gas turbine stator assembly, the thickness of the turbine casing at the electron beam welding location is 1 / 2-2 / 3 of the axial length of the turbine stator blade grid composed of a plurality of turbine stator blades.

[0016] The present invention also provides a gas turbine, comprising the gas turbine stator assembly according to any one of claims 1-8.

[0017] Compared with the prior art in which no annular groove is provided, the oxygen pump chamber connected to the inner circumference of the turbine stator disk, the flow path of the cryogenic liquid oxygen from the oxygen pump chamber is adjacent to the inner circumference and outer wall of the turbine stator disk, and the large temperature difference between the high-temperature combustion gas flow path and the cryogenic liquid oxygen flow path causes the turbine stator disk structure to be subjected to large temperature stress. In the gas turbine stator assembly provided by the present invention, an annular groove concentric with the disk surface of the turbine stator disk in contact with the flow path of the cryogenic liquid oxygen is provided, and the groove surface of the annular groove forms a thin-walled structure with the outer circumference of the turbine stator disk and the disk surface of the turbine stator disk. Compared with the overall structure of the turbine stator disk, the thin-walled structure is relatively isolated. In this way, a radially isolated thin-walled structure is actively constructed, so that the temperature stress borne by the turbine stator disk is actively released in this radially isolated thin-walled structure, reducing the deformation of the turbine stator structure caused by the temperature stress, and avoiding the strength reduction caused by the deformation of the structure.

[0018] The present invention also provides a gas turbine, comprising a gas turbine stator assembly as described in any one of the above claims and a turbine rotor disk matched with the gas turbine stator assembly.

[0019] Compared with the prior art, the beneficial effects of the gas turbine provided by the present invention are the same as the beneficial effects of the gas turbine stator assembly described in the above technical solution, which will not be described in detail here. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0021] Figure 1 It is a schematic diagram of the cooperation between a turbine stator assembly and a turbine rotor disc proposed in an embodiment of the present invention;

[0022] Figure 2 It is a schematic structural diagram of a gas turbine stator assembly proposed in an embodiment of the present invention.

[0023] Reference numerals: 1 is a turbine casing, 2 is a turbine stator blade, 3 is a turbine moving disk, 4 is a turbine stator disk, 41 is an annular groove, 42 is an annular boss, and 5 is a concave cavity. DETAILED DESCRIPTION

[0024] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0025] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it can be directly on the other element or indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or indirectly connected to the other element.

[0026] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "multiple" is two or more, unless otherwise clearly and specifically defined. The meaning of "several" is one or more, unless otherwise clearly and specifically defined.

[0027] In the description of the present invention, it is necessary to understand that the directions or positional relationships indicated by the terms "up", "down", "front", "back", "left", "right", etc. are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation on the present invention.

[0028] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0029] See also Figure 1 The gas turbine stator assembly provided by the embodiment of the present invention comprises: a turbine casing 1, a plurality of turbine stator blades 2 and a turbine stator disk 4, wherein one end of the plurality of turbine stator blades 2 is fixedly connected to the inside of the turbine casing 1, and extends radially from the inner circumference of the turbine casing 1 to the turbine casing 1; the turbine stator disk 4 is in the shape of a disc, and a through hole is provided at the center of the disc surface of the turbine stator disk 4, and the through hole is used to pass through the turbine moving disk 3, and the other end of the turbine stator blade 2 is fixedly connected to the outer circumference of the turbine stator disk 4, and an annular groove 41 is provided on the disc surface of the turbine stator disk 4 facing the same-level turbine moving disk 3, and the annular groove 41 is provided concentrically with the disc surface of the turbine stator disk 4.

[0030] During specific implementation: an annular groove 41 concentric with the disk surface of the turbine stator 4 in contact with the flow path of the cryogenic liquid oxygen is provided, and the recessed groove surface of the annular groove 41 and the outer peripheral surface of the turbine stator 4 and the disk surface of the turbine stator 4 form a thin-walled structure. Compared with the overall structure of the turbine stator 4, the thin-walled structure is relatively isolated. In this way, a radially isolated thin-walled structure is actively constructed, so that the temperature stress borne by the turbine stator 4 is actively released in this radially isolated thin-walled structure, thereby reducing the deformation of the turbine stator structure caused by the temperature stress and avoiding the reduction of strength caused by the deformation of the structure.

[0031] As a possible implementation, Figure 1As shown, the radial distance between the groove edge of the annular groove 41 away from the center of the disk surface of the turbine stator 4 and the edge of the outer peripheral surface of the turbine stator 4 is B, and B is 3mm-5mm greater than the blade thickness of the turbine stator 2 at the contact point with the turbine stator 4. In order to better achieve the effect of actively releasing the temperature stress of the turbine stator structure, the radial distance between the opening starting position of the annular groove 41 and the outer peripheral surface of the turbine stator 4 is set to an interval, and this interval is 3mm-5mm greater than the blade thickness of the turbine stator 2 at the contact point with the turbine stator 4. The purpose of such setting is to control the radial wall thickness of the isolated thin-walled structure formed by the groove surface of the annular groove 41 and the outer peripheral surface of the turbine stator 4 and the axial disk surface of the turbine stator 4, so as to better achieve the effect of releasing thermal stress under the premise of ensuring the strength of the isolated thin-walled structure. Compared with the turbine stator without the annular groove 41, the isolated thin-walled structure formed by the annular groove 41 has a 20% decrease in the overall structural stress level, thereby improving the reliability of the turbine stator structure.

[0032] As a possible implementation, Figure 1 As shown, the axial depth of the annular groove 41 is 1 / 4-1 / 3 of the axial length of the turbine stator blade grid composed of multiple turbine stator blades 2. It should be noted that when the annular groove 41 is opened, the distance between the bottom of the annular groove 41 and the concave cavity 5 needs to be considered, and the structural strength needs to be considered. There is high-pressure liquid oxygen in the concave cavity 5, and there is relatively low-pressure high-temperature combustion gas in the annular groove 41. If the distance between the bottom of the annular groove 41 and the concave cavity 5 is too close, the thin walls formed on both sides of the close distance will be subjected to a large pressure difference, resulting in instability of the overall structure and easy deformation. If the distance between the bottom of the annular groove 41 and the concave cavity 5 is too far, that is, the axial depth of the annular groove 41 is too shallow, the isolated thin-walled structure formed by the groove surface of the annular groove 41 and the outer peripheral surface of the turbine stator 4 and the axial disk surface of the turbine stator 4 will be too small, and it will not be able to play a good role in actively releasing temperature stress. The beneficial effect of setting the axial depth of the annular groove 41 to 1 / 4-1 / 3 of the axial length of the turbine stator blade grid composed of multiple turbine stator blades 2 is: the stress level of the turbine stator 4 is reduced by 20%, which will not weaken the structural strength and effectively reduce the influence of deformation of the turbine stator structure caused by temperature stress on the performance of the turbine stator structure.

[0033] As a possible implementation method, a concave cavity 5 is opened along the inner circumference of the turbine stator 4. The concave cavity 5 is opened in the turbine stator 4 along the inner circumference of the turbine stator 4 radially away from the turbine moving disk 3. The gas turbine stator assembly is also provided with an annular boss 42. The annular boss 42 is opened on the disk surface of the turbine stator 4 facing the turbine moving disk 3 of the same level. The annular boss 42 is concentrically arranged with the disk surface of the turbine stator 4, and the axial surface of the annular boss 42 is penetrated by the axial extension surface of the axial surface of the concave cavity 5 radially away from the edge of the turbine moving disk 3. That is, the annular boss 42 is opened on the disk surface of the turbine stator 4 relative to the turbine moving disk 3 of the same level, and is concentrically arranged with the disk surface of the turbine stator 4. The annular boss 42 is opened around the center of the disk surface of the turbine stator 4. Since the turbine stator 4 is a disc-shaped structure, on the one hand, in order to make the structure have better strength, the boss is set as an annular boss 42, which is opened around the center of the disk surface of the turbine stator 4. In this way, the continuity of the annular boss 42 is maintained, and the structure has better strength; on the other hand, the purpose of setting the annular boss 42 is to improve the overall stiffness of the turbine stator structure and reduce the deformation of the turbine stator structure.

[0034] It should be noted that the concave cavity 5 is an oxygen pump cavity, which is filled with low-temperature high-pressure liquid oxygen. A disengageable end face sealing structure is provided between the oxygen pump cavity and the turbine stator 4. In the stable working stage of the engine, the high-pressure liquid oxygen in the oxygen pump flows to the end face seal, and the end face seal is disengaged under the action of the high-pressure liquid oxygen. The leaked high-pressure liquid oxygen displaces the high-temperature combustion gas in the turbine cavity away from the turbine cavity, thereby preventing the high-temperature combustion gas from flowing back to the oxygen pump cavity and causing cavitation in the oxygen pump cavity. The low-temperature high-pressure liquid oxygen that displaces the combustion gas flows between the turbine stator and the turbine blades, and after being mixed and gasified with the high-temperature high-pressure combustion gas on one side of the turbine stator 4, it drives the turbine blades to work together. The turbine stator located between the oxygen pump cavity and the gap between the turbine stator 4 and the turbine rotor 3 forms a thin-walled structure, one side of which contacts low-temperature high-pressure liquid oxygen, and the other side contacts high-temperature low-pressure combustion gas. Therefore, this thin-walled structure will bear the mechanical stress under the high-pressure environment, so that this thin-walled structure will generate an axial torsion force, so the radial surface of the turbine stator 4 close to the turbine rotor 3 has the risk of dynamic and static friction with the turbine rotor 3. Therefore, an axial annular boss 42 is arranged on the disk surface of the turbine stator 4, the purpose of which is to thicken the points that are prone to deformation at the thin-walled structure, improve the stiffness here, and make it less likely to deform. Compared with the turbine stator without the axial annular boss 42 structure, the radial deformation of the structure under the combined action of large temperature difference and high pressure difference is reduced by 12.5%, reducing the risk of dynamic and static friction between the turbine stator and the shaft, and improving the radial working clearance safety margin between the turbine stator and the turbine rotor 3.

[0035] It is worth mentioning that the temperature range of high-temperature low-pressure fuel gas is 400 degrees Celsius to 550 degrees Celsius, the temperature range of low-temperature high-pressure liquid oxygen is -160 degrees Celsius to -120 degrees Celsius, and the pressure difference between the two is 6MPa-10MPa.

[0036] Furthermore, the axial height of the annular boss 42 is 1.5mm-4mm. That is, the axial height of the annular boss 42 extending axially relative to the disk surface of the turbine stator 4 is 1.5mm-4mm. As can be seen from the above, the purpose of setting the annular boss 42 is to increase the rigidity and prevent the relatively weak thin-walled structure from being deformed due to pressure difference and temperature difference. It is proposed that the preferred height of the annular boss 42 is 1.5mm-4mm. The height of the annular boss 42 within this range can achieve a good effect of increasing the rigidity. If it exceeds this range, the effect of increasing the rigidity will not be significantly improved, and it will affect the flow of low-temperature oxygen, so that the low-temperature oxygen cannot play a good role in blocking the high-temperature combustion gas from invading the disk cavity, and it will increase the weight of the structure, causing unnecessary weight burden on the operation of the structure; if the height of the annular boss 42 is lower than this range, it cannot achieve the expected effect of increasing the rigidity.

[0037] In some embodiments, Figure 2 As shown, the side wall surface of the annular boss 42 away from the center of the disk surface is the groove wall surface of the annular groove 41 close to the center of the disk surface. That is, if the radial surface of the annular groove 41 away from the turbine rotor disk 3 is defined as the outer ring surface of the annular groove 41, and the radial surface of the annular groove 41 close to the turbine rotor disk 3 is defined as the inner ring surface of the annular groove 41, the inner ring surface is axially extended and bent to form a side wall surface of the annular boss 42. The purpose of such a setting is to shrink the spatial position of the additional structure opened on the turbine stator 4 to a smaller range, which reduces the impact on the structural strength of the turbine stator compared to setting it at two different positions.

[0038] As a possible implementation method, the turbine stator blade 2 is electron beam welded to the turbine casing 1. One end of the turbine stator blade 2 is electron beam welded to the casing to form a turbine stator assembly. Electron beam welding uses a high-energy electron beam as a processing heat source, and bombards the guide component and the part of the casing to be welded with a high-energy density electron beam to make it melt quickly, and then quickly cool to achieve the purpose of welding. The weld after electron beam welding is not easy to oxidize and has a small amount of thermal deformation. During the operation of the engine, high-temperature fuel gas is passed through the casing at the weld, so the weld of the casing is prone to thermal deformation. Due to the good performance of electron beam welding, thermal deformation can be effectively prevented.

[0039] It is worth mentioning that the turbine stator blades 2 may be welded to the turbine casing 1 by submerged arc welding or other welding methods.

[0040] Furthermore, the thickness of the turbine casing 1 at the electron beam welding position is 1 / 2-2 / 3 of the axial length of the turbine stator blade grid composed of multiple turbine stator blades 2. When welding by electron beam welding, the structural thickness of the turbine casing 1 at the welding position needs to be considered. In this embodiment, electron beam welding is performed at the axial length of the turbine stator blade grid where the thickness of the turbine casing 1 is 1 / 2-2 / 3, and the turbine stator blade grid and the turbine casing 1 are welded into an assembly. The purpose of limiting the structural wall thickness of the turbine casing 1 at the welding position to this range is that, on the one hand, such a wall thickness can ensure that the electron beam weld can be fully penetrated, ensuring the welding quality of the weld, and such an appropriate wall thickness ensures the structural strength of the turbine stator; on the other hand, considering that electron beam welding uses a high-energy electron beam for welding, a large amount of energy will be released, such an appropriate wall thickness can control the welding energy of the electron beam weld, reduce the influence of the heat energy converted from the energy at the weld on the deformation of the turbine stator blade grid structure, thereby preventing the influence of the weld heat energy on the turbine starting performance.

[0041] An embodiment of the present invention further provides a gas turbine, comprising a gas turbine stator assembly as recited in any one of the above claims and a turbine rotor 3 matched with the gas turbine stator assembly.

[0042] Compared with the prior art, the beneficial effects of the gas turbine provided by the embodiment of the present invention are the same as the beneficial effects of the gas turbine stator assembly provided by the above technical solution, which will not be elaborated here.

[0043] In the description of the above embodiments, specific features, structures, materials or characteristics may be combined in a suitable manner in any one or more embodiments or examples.

[0044] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A gas turbine stator assembly, characterized in that: include: turbine casing; A plurality of turbine stator blades, one end of each of which is fixedly connected to the interior of the turbine casing and extends from the inner circumference of the turbine casing to the radial direction of the turbine casing; The turbine stator is in the shape of a circular disk, a through hole is provided at the center of the disk surface of the turbine stator, the through hole is used to pass through the turbine moving disk, the other end of the turbine stator blade is fixedly connected to the outer peripheral surface of the turbine stator, an annular groove is provided on the disk surface of the turbine stator facing the moving disk of the same level turbine, and the annular groove is provided concentrically with the disk surface of the turbine stator.

2. The gas turbine stator assembly according to claim 1, characterized in that: The radial distance between the groove edge of the annular groove away from the disk center of the turbine stator and the edge of the outer peripheral surface of the turbine stator is B, and B is 3mm-5mm larger than the blade thickness of the turbine stator at the contact point with the turbine stator.

3. The gas turbine stator assembly according to claim 1, characterized in that: The axial depth of the annular groove is 1 / 4-1 / 3 of the axial length of the turbine stator blade grid composed of a plurality of the turbine stator blades.

4. The gas turbine stator assembly according to claim 1, characterized in that: A concave cavity is opened along a circle of the inner circumference of the turbine stator disk, and the concave cavity is opened in the turbine stator disk along the inner circumference of the turbine stator disk in a direction radially away from the turbine moving disk. The gas turbine stator assembly is also provided with an annular boss, and the annular boss is opened on the disk surface of the turbine stator disk facing the turbine moving disk of the same level. The annular boss is concentrically arranged with the disk surface of the turbine stator disk, and the axial surface of the annular boss is penetrated by the axial extension surface of the axial surface of the concave cavity which is radially away from the edge of the turbine moving disk.

5. The gas turbine stator assembly according to claim 4, characterized in that: The axial height of the annular boss is 1.5 mm-4 mm.

6. The gas turbine stator assembly according to claims 3 and 4, characterized in that The side wall surface of the annular boss away from the center of the disk surface is the groove wall surface of the annular groove close to the center of the disk surface.

7. The gas turbine stator assembly according to claim 1, characterized in that: The turbine stator blades are electron beam welded to the turbine casing.

8. The gas turbine stator assembly according to claim 7, characterized in that: The thickness of the turbine casing at the electron beam welding location is 1 / 2-2 / 3 of the axial length of the turbine stator blade grid composed of a plurality of the turbine stator blades.

9. A gas turbine, characterized in that: Comprising a gas turbine stator assembly as claimed in any one of claims 1 to 8.

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