CN111571154A - Stator blade design method based on UG, stator blade and stator casing structure thereof - Google Patents
Stator blade design method based on UG, stator blade and stator casing structure thereof Download PDFInfo
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- CN111571154A CN111571154A CN202010439477.5A CN202010439477A CN111571154A CN 111571154 A CN111571154 A CN 111571154A CN 202010439477 A CN202010439477 A CN 202010439477A CN 111571154 A CN111571154 A CN 111571154A
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- China
- Prior art keywords
- edge plate
- stator
- upper edge
- lower edge
- outer ring
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- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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Classifications
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23P—METAL-WORKING NOT OTHERWISE PROVIDED FOR; COMBINED OPERATIONS; UNIVERSAL MACHINE TOOLS
- B23P15/00—Making specific metal objects by operations not covered by a single other subclass or a group in this subclass
- B23P15/04—Making specific metal objects by operations not covered by a single other subclass or a group in this subclass turbine or like blades from several pieces
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01D—NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
- F01D9/00—Stators
- F01D9/02—Nozzles; Nozzle boxes; Stator blades; Guide conduits, e.g. individual nozzles
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01D—NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
- F01D9/00—Stators
- F01D9/02—Nozzles; Nozzle boxes; Stator blades; Guide conduits, e.g. individual nozzles
- F01D9/04—Nozzles; Nozzle boxes; Stator blades; Guide conduits, e.g. individual nozzles forming ring or sector
- F01D9/041—Nozzles; Nozzle boxes; Stator blades; Guide conduits, e.g. individual nozzles forming ring or sector using blades
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01D—NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
- F01D9/00—Stators
- F01D9/02—Nozzles; Nozzle boxes; Stator blades; Guide conduits, e.g. individual nozzles
- F01D9/04—Nozzles; Nozzle boxes; Stator blades; Guide conduits, e.g. individual nozzles forming ring or sector
- F01D9/042—Nozzles; Nozzle boxes; Stator blades; Guide conduits, e.g. individual nozzles forming ring or sector fixing blades to stators
- F01D9/044—Nozzles; Nozzle boxes; Stator blades; Guide conduits, e.g. individual nozzles forming ring or sector fixing blades to stators permanently, e.g. by welding, brazing, casting or the like
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Structures Of Non-Positive Displacement Pumps (AREA)
Abstract
The present application specifically relates to a stator blade design method based on UG, which includes: obtaining a curved blade body of the stator blade through the curve group; processing the boundary curve at the upper end of the curved blade body by designing characteristic rotation to obtain an upper edge plate outer ring; summing the curved blade body and the outer ring of the upper edge plate, and performing surface rounding treatment to obtain the surface rounding of the upper edge plate; the tangent of the upper edge plate surface rounding and the outer ring of the upper edge plate is the tangent of the upper edge plate; stretching and offsetting the tangent line of the upper edge plate to obtain a sheet body for trimming the upper edge plate; and trimming the outer ring of the upper edge plate by using the upper edge plate trimming sheet body by modifying the characteristics of the upper edge plate to obtain the upper edge plate of the stator blade. The present application also relates to a stator vane having a configuration corresponding to that of a stator vane designed by the UG-based stator vane design method, and a stator case structure having a plurality of the stator vanes.
Description
Technical Field
The application belongs to the technical field of structural design of engine stator casings, and particularly relates to a stator blade design method based on UG, a stator blade and a stator casing structure of the stator blade.
Background
The existing stator casing structure includes: the stator casing is provided with a plurality of limiting holes distributed along the circumferential direction; an inner ring arranged in the stator casing; a plurality of stator blades circumferentially distributed between the stator casing and the inner ring; the upper end of each stator blade is provided with an upper edge plate, and the lower end of each stator blade is provided with a lower edge plate; the lower edge plate of each stator blade is welded with the inner ring, and the upper edge plate is correspondingly inserted into a limiting hole and is welded with the stator casing.
At present, in a stator casing structure, an upper edge plate of each stator blade has a relatively large sectional area, and the area of each limiting hole on the stator casing is correspondingly large, so that the rigidity of the stator casing is seriously damaged, and the stator casing is easy to deform in the working process of an engine and seriously affects the normal work of the engine; in addition, in order to detect the interior of the stator casing, a hole detector hole seat is welded on the stator casing, the hole detector hole seat is located between the upper edge plates of two adjacent stator blades, and under the condition that the sectional area of the upper edge plates of the two stator blades is large, the hole detector hole seat and the heat affected zone of the upper edge plates of the two stator blades on the stator casing can be intersected, so that high residual stress exists, and cracks are easily generated at the corresponding welding part in the working process of an engine, even the corresponding welding part is broken, and catastrophic accidents are caused.
The present application has been made in view of the above-mentioned technical drawbacks.
It should be noted that the above background disclosure is only for the purpose of assisting understanding of the inventive concept and technical solutions of the present invention, and does not necessarily belong to the prior art of the present patent application, and the above background disclosure should not be used for evaluating the novelty and inventive step of the present application without explicit evidence to suggest that the above content is already disclosed at the filing date of the present patent application.
Disclosure of Invention
The present application is directed to a UG-based stator blade design method, a stator blade and a stator casing structure thereof, which overcome or alleviate at least one of the known technical disadvantages.
The technical scheme of the application is as follows:
in one aspect, a UG-based stator blade design method is provided, including:
obtaining a curved blade body of the stator blade through the curve group;
processing the boundary curve at the upper end of the curved blade body by designing characteristic rotation to obtain an upper edge plate outer ring;
summing the curved blade body and the outer ring of the upper edge plate, and performing surface rounding treatment to obtain the surface rounding of the upper edge plate; the tangent of the upper edge plate surface rounding and the outer ring of the upper edge plate is the tangent of the upper edge plate;
stretching and offsetting the tangent line of the upper edge plate to obtain a sheet body for trimming the upper edge plate;
and trimming the outer ring of the upper edge plate by using the upper edge plate trimming sheet body by modifying the characteristics of the upper edge plate to obtain the upper edge plate of the stator blade.
According to at least one embodiment of the present application, the UG-based stator blade design method further includes:
processing a boundary curve at the lower end of the curved blade body by designing characteristic rotation to obtain a lower edge plate outer ring;
summing the curved blade body and the outer ring of the lower edge plate, and performing surface rounding treatment to obtain a lower edge plate surface rounding; the tangent line of the lower edge plate surface rounding and the outer ring of the lower edge plate is the tangent line of the lower edge plate;
stretching and offsetting the tangent of the lower edge plate to obtain a sheet body for trimming the lower edge plate;
and trimming the outer ring of the lower edge plate by using the sheet body for trimming the lower edge plate by modifying the characteristics of the body to obtain the lower edge plate of the stator blade.
Another aspect provides a stator vane having a configuration conforming to a configuration of a stator vane designed by any of the above-described UG-based stator vane design methods.
Still another aspect provides a stator case structure, including:
the stator casing is provided with a plurality of limiting holes distributed along the circumferential direction;
an inner ring arranged in the stator casing;
a plurality of stator blades arranged between the stator casing and the inner ring; the lower edge plate of each stator blade is connected with the inner ring, and the upper edge plate is correspondingly inserted into one limiting hole.
According to at least one embodiment of the present application, in the above-described stator case structure, the lower edge plate of each stator blade is welded to the inner ring by electron beam welding.
According to at least one embodiment of the present application, in the above-described stator case structure, the upper flange plate and the stator case are welded by electron beam welding.
According to at least one embodiment of the present application, the above-mentioned stator casing structure further includes:
and the hole detector hole seat is welded on the stator casing through electron beams and is positioned between the upper edge plates of two adjacent stator blades.
Drawings
FIG. 1 is a schematic configuration diagram of a stator blade designed by a UG-based stator blade design method provided by an embodiment of the application;
wherein:
1-curved blade body; 2-cutting the upper edge plate; 3-upper edge plate; 4-lower flange.
Detailed Description
In order to make the technical solutions and advantages of the present application clearer, the technical solutions of the present application will be further clearly and completely described in the following detailed description with reference to the accompanying drawings, and it should be understood that the specific embodiments described herein are only some of the embodiments of the present application, and are only used for explaining the present application, but not limiting the present application. It should be noted that, for convenience of description, only the parts related to the present application are shown in the drawings, other related parts may refer to general designs, and the embodiments and technical features in the embodiments in the present application may be combined with each other to obtain a new embodiment without conflict.
In addition, unless otherwise defined, technical or scientific terms used in the description of the present application shall have the ordinary meaning as understood by one of ordinary skill in the art to which the present application belongs. The terms "upper", "lower", "left", "right", "center", "vertical", "horizontal", "inner", "outer", and the like used in the description of the present application, which indicate orientations, are used only to indicate relative directions or positional relationships, and do not imply that the devices or elements must have a specific orientation, be constructed and operated in a specific orientation, and when the absolute position of the object to be described is changed, the relative positional relationships may be changed accordingly, and thus, should not be construed as limiting the present application. The use of "first," "second," "third," and the like in the description of the present application is for descriptive purposes only to distinguish between different components and is not to be construed as indicating or implying relative importance. The use of the terms "a," "an," or "the" and similar referents in the context of describing the application is not to be construed as an absolute limitation on the number, but rather as the presence of at least one. The use of the terms "comprising" or "including" and the like in the description of the present application is intended to indicate that the element or item preceding the term covers the element or item listed after the term and its equivalents, without excluding other elements or items.
Further, it is noted that, unless expressly stated or limited otherwise, the terms "mounted," "connected," and the like are used in the description of the invention in a generic sense, e.g., connected as either a fixed connection or a removable connection or integrally connected; can be mechanically or electrically connected; they may be directly connected or indirectly connected through an intermediate medium, or they may be connected through the inside of two elements, and those skilled in the art can understand their specific meaning in this application according to the specific situation.
The present application is described in further detail below with reference to fig. 1.
In one aspect, a UG-based stator blade design method is provided, including:
obtaining a curved blade body 1 of the stator blade through the curve group;
the upper edge plate outer ring is obtained by designing a characteristic rotation processing curve of the upper end of the curved blade body 1;
summing the curved blade body 1 and the outer ring of the upper edge plate, and performing surface rounding treatment to obtain the surface rounding of the upper edge plate; the tangent line of the upper edge plate surface rounding and the outer ring of the upper edge plate is the upper edge plate tangent line 2;
processing an upper edge plate tangent line 2 by stretching and offsetting, wherein the offset can be determined according to a welding influence area of an upper edge plate of the stator vane and a casing/inner ring, so as to obtain a sheet body for trimming the upper edge plate;
by modifying the body characteristics, the upper edge plate outer ring is trimmed with the upper edge plate trimming sheet body, and the upper edge plate 3 of the stator blade is obtained.
For the stator blade design method based on UG disclosed in the above embodiments, those skilled in the art can understand that the upper edge plate in the stator blade configuration obtained based on the design has a relatively small cross-sectional area under the condition of meeting the requirements, and that the stator blade obtained based on the design is applied to the stator casing structure, and the area required by each limiting hole on the stator casing is correspondingly small, so that the rigidity of the stator casing can be effectively ensured, and the influence on the normal operation of the engine due to the occurrence of severe deformation in the working process of the engine can be avoided.
In some optional embodiments, the UG-based stator blade design method further includes:
the lower end boundary curve of the curved surface blade body 1 is processed through design characteristic rotation to obtain a lower edge plate outer ring;
summing the curved blade body 1 and the outer ring of the lower edge plate, and performing surface rounding treatment to obtain the surface rounding of the lower edge plate; the tangent line of the lower edge plate surface rounding and the outer ring of the lower edge plate is the tangent line of the lower edge plate;
processing a tangent line of the lower edge plate by stretching and offsetting, wherein the offset can be determined according to a welding influence area of the lower edge plate of the stator blade and the casing/inner ring to obtain a sheet body for trimming the lower edge plate;
by modifying the body characteristics, the lower edge plate outer ring is trimmed by the sheet body for trimming the lower edge plate, and the lower edge plate 4 of the stator blade is obtained.
Another aspect provides a stator vane having a configuration conforming to a configuration of a stator vane designed by any of the above-described UG-based stator vane design methods.
For the stator blade disclosed in the above embodiment, it can be understood by those skilled in the art that the stator blade can be designed and obtained based on any of the above UG-based stator blade design methods, and the upper edge plate has a relatively small cross-sectional area under the condition that the requirements are met, and when the stator blade is applied to a stator casing structure, the area required by each limiting hole on the stator casing is correspondingly small, so that the rigidity of the stator casing can be effectively ensured, and the influence on the normal operation of an engine due to the occurrence of severe deformation in the working process of the engine can be avoided.
Still another aspect provides a stator case structure, including:
the stator casing is provided with a plurality of limiting holes distributed along the circumferential direction;
an inner ring arranged in the stator casing;
a plurality of stator blades arranged between the stator casing and the inner ring; the lower edge plate of each stator blade is connected with the inner ring, and the upper edge plate is correspondingly inserted into one limiting hole.
For the stator casing structure disclosed in the above embodiments, those skilled in the art can understand that the upper edge plate of the stator blade has a relatively small sectional area, and the area required by each limiting hole on the stator casing is also relatively small, so that the rigidity of the stator casing can be effectively ensured, and the influence on the normal operation of the engine due to the occurrence of serious deformation in the operation process of the engine can be avoided.
In some alternative embodiments, the stator case structure described above wherein the lower edge plate of each stator blade is welded to the inner ring by electron beam welding.
In some alternative embodiments, the stator case structure described above wherein the upper flange plate and the stator case are welded by electron beam welding.
In some optional embodiments, the stator casing structure further includes:
the hole detector hole seat is welded on the stator casing through the electron beams and is positioned between the upper edge plates of two adjacent stator blades, and the cross section area of the upper edge plates of the stator blades is relatively small, so that the possibility of intersecting with a welding heat influence area of the hole detector hole seat on the stator casing is reduced, the existence of high residual stress is avoided, and cracks are prevented from easily growing at corresponding welding parts in the working process of an engine.
The embodiments are described in a progressive manner in the specification, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments are referred to each other.
Having thus described the present application in connection with the preferred embodiments illustrated in the accompanying drawings, it will be understood by those skilled in the art that the scope of the present application is not limited to those specific embodiments, and that equivalent modifications or substitutions of related technical features may be made by those skilled in the art without departing from the principle of the present application, and those modifications or substitutions will fall within the scope of the present application.
Claims (7)
1. A stator blade design method based on UG is characterized by comprising the following steps:
obtaining a curved blade body (1) of the stator blade through a curve group;
the upper end boundary curve of the curved blade body (1) is subjected to characteristic rotation processing to obtain an upper edge plate outer ring;
summing the curved blade body (1) and the outer ring of the upper edge plate, and performing surface rounding treatment to obtain the upper edge plate surface rounding; the tangent line of the upper edge plate surface rounding and the outer ring of the upper edge plate is the upper edge plate tangent line (2);
stretching and offsetting the upper edge plate tangent line (2) to obtain a sheet body for trimming the upper edge plate;
and trimming the outer ring of the upper edge plate by using the upper edge plate trimming sheet body by modifying the characteristics of the upper edge plate to obtain the upper edge plate (3) of the stator blade.
2. A stator blade design method based on UG is characterized in that,
further comprising:
the lower end boundary curve of the curved blade body (1) is subjected to characteristic rotation processing to obtain a lower edge plate outer ring;
summing the curved blade body (1) and the outer ring of the lower edge plate, and performing surface rounding treatment to obtain the surface rounding of the lower edge plate; the tangent line of the lower edge plate surface rounding and the outer ring of the lower edge plate is the tangent line of the lower edge plate;
stretching and offsetting the tangent of the lower edge plate to obtain a sheet body for trimming the lower edge plate;
and trimming the outer ring of the lower edge plate by using the sheet body for trimming the lower edge plate by modifying the characteristics of the body to obtain the lower edge plate (4) of the stator blade.
3. A stator vane characterized by a configuration conforming to that of a stator vane designed by the UG-based stator vane design method as recited in any one of claims 1 to 2.
4. A stator case structure, comprising:
the stator casing is provided with a plurality of limiting holes distributed along the circumferential direction;
an inner ring arranged in the stator casing;
a plurality of stator vanes as set forth in claim 3 disposed between the stator case and the inner ring; the lower edge plate of each stator blade is connected with the inner ring, and the upper edge plate is correspondingly inserted into one limiting hole.
5. The stator case structure according to claim 4,
the lower edge plate of each stator blade is welded with the inner ring through electron beam welding.
6. The stator case structure according to claim 4, wherein the upper flange plate and the stator case are welded by electron beam welding.
7. The stator case structure according to claim 6,
further comprising:
and the hole detector hole seat is welded on the stator casing through electron beams and is positioned between the upper edge plates of two adjacent stator blades.
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CN202010439477.5A CN111571154B (en) | 2020-05-22 | 2020-05-22 | Stator blade design method based on UG, stator blade and stator casing structure thereof |
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CN202010439477.5A CN111571154B (en) | 2020-05-22 | 2020-05-22 | Stator blade design method based on UG, stator blade and stator casing structure thereof |
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CN111571154B CN111571154B (en) | 2021-03-26 |
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Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN116441696A (en) * | 2023-06-19 | 2023-07-18 | 中国航发成都发动机有限公司 | Vacuum electron beam welding method and clamping device for stator assembly of aero-engine |
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CN116441696B (en) * | 2023-06-19 | 2023-09-15 | 中国航发成都发动机有限公司 | Vacuum electron beam welding method and clamping device for stator assembly of aero-engine |
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