CN116537886B - Blade top structure and blade with improve cooling efficiency - Google Patents
Blade top structure and blade with improve cooling efficiencyInfo
- Publication number
- CN116537886B CN116537886B CN202310706155.6A CN202310706155A CN116537886B CN 116537886 B CN116537886 B CN 116537886B CN 202310706155 A CN202310706155 A CN 202310706155A CN 116537886 B CN116537886 B CN 116537886B
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- Prior art keywords
- blade
- groove
- cooling
- wall
- blade tip
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Classifications
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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
- F01D5/00—Blades; Blade-carrying members; Heating, heat-insulating, cooling or antivibration means on the blades or the members
- F01D5/12—Blades
- F01D5/14—Form or construction
- F01D5/141—Shape, i.e. outer, aerodynamic form
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
- Y02T50/00—Aeronautics or air transport
- Y02T50/60—Efficient propulsion technologies, e.g. for aircraft
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- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Fluid Mechanics (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Turbine Rotor Nozzle Sealing (AREA)
Abstract
本发明公开了一种具有提高冷却效率的叶顶结构及叶片，包括形成在叶顶间隙泄漏流流动区域的凹槽，凹槽的内壁向叶片的中弧线倾斜，叶片的冷却孔的出口位于凹槽的内壁上，冷却孔输出的冷却工质的流向与泄漏流流动方向相同，将燕尾式凹槽和冷却孔结合，燕尾式凹槽抑制了压力侧角涡的形成，减少近压力面侧的换热系数；冷却孔将冷气直接吹出至叶顶高换热区域进行冲击冷却，冷气冲击冷却后在压差作用下向吸力面侧流动对壁面冷却，提升冷气利用率、均匀叶顶温度分布；另一方面，高速冷却射流形成近似周向肋结构，起到气动封严作用，抑制泄漏流向下游发展，减少叶顶泄漏量，提高了叶顶区域的气热特性，延长高压涡轮动叶的使用寿命并保障燃气涡轮安全有效地运行。
This invention discloses a blade tip structure and blade with improved cooling efficiency, including a groove formed in the leakage flow region of the blade tip clearance. The inner wall of the groove is inclined towards the mid-arc line of the blade. The outlet of the cooling hole of the blade is located on the inner wall of the groove. The flow direction of the cooling working fluid output from the cooling hole is the same as the flow direction of the leakage flow. The dovetail-shaped groove and the cooling hole are combined. The dovetail-shaped groove suppresses the formation of pressure-side angular vortices and reduces the heat transfer coefficient near the pressure surface. The cooling hole blows cold air directly to the high heat transfer region of the blade tip for impact cooling. After impact cooling, the cold air flows towards the suction surface under the action of pressure difference to cool the wall, improving the utilization rate of cold air and uniform blade tip temperature distribution. On the other hand, the high-speed cooling jet forms an approximately circumferential rib structure, which plays a pneumatic sealing role, suppressing the downstream development of the leakage flow, reducing the blade tip leakage, improving the aero-thermal characteristics of the blade tip region, extending the service life of the high-pressure turbine blade, and ensuring the safe and efficient operation of the gas turbine.
Description
Technical Field
The invention relates to the technical field of cooling of gas turbine blades, in particular to a turbine rotor blade top structure and a blade.
Background
With the rapid development of the aviation industry in recent years, various aspects of performances of an aeroengine face higher requirements, in order to improve thrust ratio and reduce oil consumption, the front inlet temperature of a turbine must be improved to improve thermal efficiency, but this also brings a series of serious problems to normal operation of the engine, the improvement speed of the inlet temperature of the turbine is far higher than the development speed of the temperature resistance of blade materials, particularly for the first-stage blade of a high-pressure turbine, the blade tip is subjected to oxidation and corrosion phenomena in a high-temperature environment for a long time, and further the performances and the service life of the blade are affected.
The groove blade top structure can effectively reduce leakage loss, the existing blade top groove structure is more in use on the turbine blade top, compared with a flat blade top, leakage flow of the blade top can be obviously restrained, but the leakage flow can cause higher temperature and heat load on the wall surface of the blade tip end region, and further the reliability and the service life of the turbine tip region are threatened.
Disclosure of Invention
Aiming at the problems in the prior art, the invention provides the blade top structure and the blade with improved cooling efficiency, and the design is carried out on the top structure of the turbine movable blade, so that the pneumatic loss caused by leakage of the blade top can be effectively reduced, the heat exchange characteristic of the blade top area is improved, the service life of the blade is prolonged, and the working efficiency of the turbine blade is improved.
The invention is realized by the following technical scheme:
The utility model provides a top of leaf structure with improve cooling efficiency, includes the recess that forms in top of the leaf clearance leakage flow region, and the recess extends to the tail of the leaf from the apex of the blade, and the camber line slope of the inner wall of recess from bottom to top to the blade, and the export of the cooling hole of blade is located the inner wall of recess, and the flow direction of the cooling medium of cooling hole output is the same with leakage flow direction for strike the cooling to the recess bottom surface.
Preferably, the front end and the rear end of the groove are plane and perpendicular to the camber line of the blade.
Preferably, the inner wall of the pressure side or/and the suction side of the groove is inclined from bottom to top to the camber line of the blade.
Preferably, the outlets of the cooling holes 5 are located on the pressure side or/and suction side inner wall of the groove.
Preferably, the inner wall of the pressure side of the groove is inclined from bottom to top to the camber line of the blade, and the inner wall of the suction side of the groove is vertical to the bottom surface of the groove.
Preferably, the cooling holes are provided on the pressure side inner wall.
Preferably, the included angle between the bottom surface of the groove and the side wall is 15-75 degrees.
Preferably, the width of the upper shoulder wall of the groove is 2-4G, the width of the upper shoulder wall of the groove is 0.5-1.5G, and G is the height of the blade tip clearance.
9. The blade is characterized in that the top of the blade is provided with the blade top structure with the improved cooling efficiency.
A turbine engine having the above-described tip structure with improved cooling efficiency provided on rotor blades thereof.
Compared with the prior art, the invention has the following beneficial technical effects:
According to the blade top structure with improved cooling efficiency, the grooves are formed in the blade top clearance leakage flow flowing area of the blade, the upper ends of the inner walls of the grooves incline towards the camber line direction, the outlets of the cooling holes are arranged on the inner walls of the grooves, so that the flowing direction of cooling working media is the same as the flowing direction of leakage flow, the dovetail grooves are combined with the cooling holes by the blade top structure, the formation of pressure side corner vortex is restrained by the inner walls of the grooves, the heat exchange coefficient of the near pressure surface side is reduced, the cooling working media can be directly output to the blade top high heat exchange area by the cooling holes for impact cooling, the cooling working media can be cooled towards the suction surface side by the impact cooling working media under the action of pressure difference, the utilization rate of the cooling working media is improved, the blade top heat exchange coefficient can be reduced by uniform blade top temperature distribution, meanwhile, the high-speed cooling jet forms an approximate circumferential rib structure, the pneumatic sealing effect is realized, the downstream development of the leakage flow is restrained, the leakage quantity of the blade top is reduced, the gas thermal characteristics of the blade top area are improved, the leakage flow of the blade top clearance is restrained, the leakage flow is reduced, the effect of the flow is restrained, the effect of the flow is effectively cooled by the cooling jet flow is impacted by the cooling jet flow, the bottom surface is cooled, the effect is prolonged, the service life of the turbine is effectively cooled, and the service life of the turbine is ensured, and safe running is ensured.
And secondly, the front end and the rear end of the groove are perpendicular to the camber line of the blade tip, so that the groove is integrally formed into an approximately rectangular structure, the development of the vortex of the groove cavity is blocked, and the heat exchange characteristic from the chord to the tail edge of the blade tip is improved.
Drawings
FIG. 1 is a schematic view of a turbine rotor blade tip structure according to embodiment 1 of the present invention;
FIG. 2 is a top view of a turbine rotor blade tip structure according to embodiment 1 of the present invention;
FIG. 3 is a right side view of the tip structure of the turbine rotor of example 1 of the present invention;
FIG. 4 is a cross-sectional view of a turbine rotor blade tip structure A-A according to example 1 of the present invention.
FIG. 5 is a three-dimensional streamline comparison of prior art and inventive turbine rotor tip structures, (a) is a three-dimensional streamline of a conventional film cooled tip, and (b) is a three-dimensional streamline of an inventive tip.
FIG. 6 is a graph showing the comparison of the air film cooling effect distribution of the prior art and the turbine rotor blade tip structure of the present invention, wherein (a) is the air film cooling effect distribution of the conventional air film cooling blade tip, and (b) is the air film cooling effect distribution of the blade tip of the present invention.
In the figure, the blade is 1-, the blade tip is 2-, the groove bottom is 3-, the pressure side shoulder wall is 4-, the cooling hole is 5-, the suction side shoulder wall is 6-, the front end of the groove is 7-, the rear end of the groove is 8-and the turbine casing is 9-.
Detailed Description
The invention will now be described in further detail with reference to the accompanying drawings, which illustrate but do not limit the invention.
The utility model provides a tip structure with improve cooling efficiency, including forming the cooling hole in inside blade 1, and the recess of formation at tip 2, the recess extends to the tail from the apex of the blade, the pitch arc slope of the pressure side or/and suction side inner wall of recess from bottom to top to the blade, the export of cooling hole 5 is located on the pressure side or/and the suction side inner wall of recess, the flow direction of the cooling medium of cooling hole 5 output is the same with leakage flow direction, be used for carrying out the impingement cooling to recess bottom surface 3.
The front end 7 of the groove and the rear end 8 of the groove are planes and perpendicular to the camber line of the blade, the front end 7 of the groove is close to the front edge of the blade, the rear end 8 of the groove is close to the tail edge of the blade, the groove extends from the front edge of the blade to the tail edge, the length L of the groove is 0.2-0.8C, the width of the shoulder wall at the top of the groove is 2-4G, the width of the shoulder wall at the bottom of the groove is 0.5-1.5G, the depth D1 of the groove is 0.5-1.5G, the included angle alpha 1 between the inner wall of the groove and the bottom surface of the groove is 15-75 degrees, and the diameter D1 of the cooling hole is 0.8-1.5G.
The shoulder wall is the distance from the side wall of the groove to the suction surface or the pressure surface of the blade, and G is the height of the clearance between the blade tip and the turbine casing, namely the distance from the blade tip 2.
According to the turbine rotor blade top structure, the grooves are formed in the blade top clearance leakage flow flowing area of the blade, extend from the front edge of the blade to the tail edge along the flow direction, the upper ends of the inner walls of the grooves incline to the camber line direction, the sections of the grooves form a dovetail groove structure, outlets of cooling holes are arranged on the inner walls of the grooves, the flow direction of cooling working mediums is the same as the flow direction of leakage flow, the cooling working mediums impact cooling the bottom surfaces of the grooves, the dovetail groove is combined with the cooling holes by the blade top structure, the formation of pressure side corner vortex is restrained by the inner walls of the grooves, the heat exchange coefficient of the side close to the pressure surface is reduced, the cooling holes can directly output the cooling working mediums to the blade top high heat exchange area for impact cooling, the cooling working mediums flow to the wall surface under the effect of pressure difference after impact cooling, the utilization rate of the cooling working mediums is improved, the blade top temperature distribution can be evenly reduced, the air heat exchange coefficient of the blade top is improved, the air heat characteristics of the blade top area are improved, the front ends and the rear ends of the grooves are perpendicular to the camber line of the blade top, the grooves are integrally formed into a similar rectangular structure, the development of a cavity of the groove is blocked, the heat exchange coefficient is improved, the heat exchange coefficient of the blade top is improved, the heat exchange efficiency of the blade top is improved, the blade top heat exchange efficiency of the blade top is improved, and the overall efficiency of the blade top efficiency is improved, and the performance of an engine is improved, and the efficiency of a rotor blade efficiency is improved.
Referring to fig. 1-2, a tip structure with improved cooling efficiency includes a groove provided in a gap leakage flow region of a tip 2, the groove extending from a leading edge of a blade toward a trailing edge in a flow direction of the blade, a pressure side inner wall of the groove being inclined from bottom to top toward a camber line of the blade, a suction side of the groove being perpendicular to a groove bottom surface 3, a groove front end 7 and a groove rear end 8 being planes perpendicular to the camber line of the blade.
Referring to fig. 3, a plurality of cooling holes 5 are provided in the blade, the inlets of the cooling holes are located at the blade root, the outlets of the cooling holes are disposed on the pressure measuring inner wall of the groove, and the flow direction of the cooling working medium output by the cooling holes 5 is the same as the flow direction of the leakage flow, so as to perform impact cooling on the bottom surface 3 of the groove.
The number of the cooling holes is 1-8, and the cooling holes are distributed at intervals along the pressure measuring inner wall of the groove.
Referring to fig. 4, the length of the groove is L0.2-0.8 c, the top width w1 of the pressure side shoulder wall 4 of the groove is 2-4 g, the bottom width w2 of the pressure side shoulder wall 4 of the groove is 0.5-1.5 g, the width w3 of the suction side shoulder wall 5 of the groove is 0.5-1.5 g, the groove depth D1 is 0.5-2 g, the included angle α1 between the pressure side inner wall of the groove and the bottom surface of the groove is 15 ° -75 °, and the diameter D1 of the cooling hole is 0.8-1.5 g.
Example 1
A blade top structure capable of improving cooling efficiency comprises a groove arranged on a blade top, wherein the inner wall of the pressure side of the groove is inclined to the camber line of a blade from bottom to top, the suction side of the groove is vertical to the bottom surface 3 of the groove, the front end 7 of the groove and the rear end 8 of the groove are planes which are vertical to the camber line of the blade, 3 cooling holes 5 are arranged in the blade, the inlets of the cooling holes are positioned at blade roots, the outlets of the cooling holes are arranged on the inner wall of the pressure measurement groove, and the flow direction of cooling working media output by the cooling holes 5 is the same as the flow direction of leakage flow and is used for performing impact cooling on the bottom surface 3 of the groove.
The length of the groove is L0.7C, the ratio of the upper shoulder wall to the lower shoulder wall of the pressure side is w 1/w2=3/2, the top width w1 of the pressure side shoulder wall 4 of the groove is 3.0mm, the bottom width w2 of the pressure side shoulder wall 4 of the groove is 2mm, the width w3 of the suction side shoulder wall 5 of the groove is 1mm, the depth D1 of the groove is 1.5mm, the included angle alpha 1 between the pressure side inner wall of the groove and the bottom surface of the groove is 30 degrees, the diameter D1 of the cooling hole is 1mm, the blade tip clearance height G is 1mm, and the blade chord length C is 57mm.
In the embodiment, the width ratio of the upper and lower shoulder walls of the pressure side dovetail groove is w1/w 2=3/2, the angle between the cooling hole and the bottom of the groove is 30 degrees, the dovetail groove belt impact cooling structure formed by different arrangement of the width ratio of the upper and lower shoulder walls of the pressure side and the angle of the cooling hole is used for inhibiting the formation of pressure side angular vortex, reducing the heat exchange coefficient of the near pressure side and reducing the heat load, and the cooling hole of the pressure side shoulder wall is used for spraying cool air to the bottom surface of the groove for impact cooling, inhibiting the flow of leakage flow at the front edge of the blade top, changing the formation of cavity vortex, cooling the blade top wall surface, inhibiting the leakage flow, improving the utilization rate of cool air and improving the gas-heat characteristic of the blade top area.
Referring to fig. 5, in this embodiment, the inner wall of the pressure side of the groove is obliquely arranged to form a dovetail groove structure, and a cooling hole is arranged on the side wall, the inclined inner wall inhibits the formation of angular vortex on the pressure side and reduces the heat exchange coefficient on the near pressure side, the cooling hole on the shoulder wall of the dovetail groove on the pressure side can directly blow out cold air to the high heat exchange area of the blade tip for impact cooling, the impact cooled cold air flows to the suction side by the action of pressure difference to cool the wall surface, and the high-speed cold air jet forms an approximate circumferential rib structure to inhibit downstream development of leakage flow, thereby effectively controlling the pneumatic loss caused by the leakage of the blade tip, improving the heat exchange characteristic of the blade tip area, prolonging the service life of the blade and improving the working efficiency of the turbine blade.
Numerical simulation results have initially demonstrated that the inventive tip structure is capable of significantly reducing the tip heat load (as shown in fig. 6).
Example 2
The blade top structure with the cooling efficiency improvement comprises cooling holes formed in a blade 1 and grooves formed in a blade top 2, wherein the grooves extend from a blade tip to a blade tail, the inner walls of a pressure side and a suction side of the grooves incline from bottom to top to a mean camber line of the blade, 8 cooling holes are uniformly formed in the pressure side and the suction side of the blade, outlets of the cooling holes are formed in the inner walls of the pressure side and the suction side of the grooves, the cooling holes in the inner walls of the pressure side and the suction side are staggered, and the flow direction of cooling working media output by the cooling holes 5 is the same as the flow direction of leakage flow and is used for performing impact cooling on the bottom surface 3 of the grooves.
In the embodiment, the inner walls of the pressure side and the suction side of the groove are inclined from bottom to top to the camber line of the blade, cooling holes are formed in the inner walls, the inclined inner walls inhibit the formation of pressure side angle vortex and suction angle vortex, the wall heat exchange coefficient of the pressure side and the suction side in the groove is reduced, the cooling holes staggered on the inner walls of the pressure side and the suction side can directly blow cold air to the wall surface of the blade top groove for impact cooling, the cold air covers the wall surface of the blade top groove in a large area and reduces the wall surface heat load, and the high-speed cold air jet forms an approximate circumferential rib structure to inhibit downstream development of leakage flow, so that the aerodynamic loss caused by the leakage of the blade top is effectively controlled, the heat exchange characteristic of the blade top area is improved, the service life of the blade is prolonged, and the working efficiency of the turbine blade is improved.
Example 3
A blade, the top of which is provided with the blade tip structure described above.
Example 4
A turbine engine has the above blade tip structure provided on a rotor blade thereof.
The above is only for illustrating the technical idea of the present invention, and the protection scope of the present invention is not limited by this, and any modification made on the basis of the technical scheme according to the technical idea of the present invention falls within the protection scope of the claims of the present invention.
Claims (4)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310706155.6A CN116537886B (en) | 2023-06-14 | 2023-06-14 | Blade top structure and blade with improve cooling efficiency |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310706155.6A CN116537886B (en) | 2023-06-14 | 2023-06-14 | Blade top structure and blade with improve cooling efficiency |
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| Publication Number | Publication Date |
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| CN116537886A CN116537886A (en) | 2023-08-04 |
| CN116537886B true CN116537886B (en) | 2025-11-07 |
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| CN202310706155.6A Active CN116537886B (en) | 2023-06-14 | 2023-06-14 | Blade top structure and blade with improve cooling efficiency |
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Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN119878316B (en) * | 2025-02-12 | 2025-10-31 | 中国航发湖南动力机械研究所 | A turbine blade tip configuration and its design method |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6672829B1 (en) * | 2002-07-16 | 2004-01-06 | General Electric Company | Turbine blade having angled squealer tip |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2982903B1 (en) * | 2011-11-17 | 2014-02-21 | Snecma | GAS TURBINE BLADE WITH INTRADOS SHIFTING OF HEAD SECTIONS AND COOLING CHANNELS |
| WO2015069411A1 (en) * | 2013-11-11 | 2015-05-14 | United Technologies Corporation | Gas turbine engine turbine blade tip cooling |
| CN112922674B (en) * | 2021-02-04 | 2022-07-26 | 南京航空航天大学 | Turbine blade with air film cooling groove |
| CN217176719U (en) * | 2022-05-11 | 2022-08-12 | 中国航发商用航空发动机有限责任公司 | Turbine blade |
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Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6672829B1 (en) * | 2002-07-16 | 2004-01-06 | General Electric Company | Turbine blade having angled squealer tip |
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