CN-121976856-A - Turbine guide vane air film hole structure and turbine guide vane

Abstract

The invention discloses a turbine guide vane air film hole structure and a turbine guide vane, wherein the turbine guide vane air film hole structure comprises at least one air film hole, the air film hole comprises a cylindrical section air cooling channel and an expansion section air cooling channel which incline along the same direction, the cylindrical section air cooling channel is communicated with the expansion section air cooling channel, the cross section of the expansion section air cooling channel is in a symmetrical pattern on the cross section perpendicular to the depth direction of the air film hole, and the symmetrical center of the cross section of the expansion section air cooling channel is positioned between the circle center and the end wall side of the cross section of the cylindrical section air cooling channel. The whole cold air channel of expansion section is offset towards the end wall side for the air film cooling jet flow direction takes place to bias, and the air film cooling gas can be transported to the position that is close to turbine stator terminal region, increases the coverage area of air film in turbine stator near-end region, and then reduces uncooled triangle area.

Inventors

• MA YUDAO
• ZHAO QINGJUN
• ZHAO WEI
• SUI XIUMING
• PU JIAN
• ZHANG JIE

Assignees

• 中国科学院工程热物理研究所

Dates

Publication Date

20260505

Application Date

20260325

Claims (10)

1. 1. Turbine vane film hole structure, both sides of the turbine vane (2) defining end wall sides (22), characterized in that the turbine vane film hole structure comprises: At least one air film hole (1), air film hole (1) are including cylinder section air conditioning passageway (11) and expansion section air conditioning passageway (12) of following the same direction slope, cylinder section air conditioning passageway (11) with expansion section air conditioning passageway (12) intercommunication, on the cross-section of perpendicular to air film hole (1) depth direction, the cross-section of expansion section air conditioning passageway (12) is symmetrical figure, the symmetry center of the cross-section of expansion section air conditioning passageway (12) is located the centre of a circle of the cross-section of cylinder section air conditioning passageway (11) with between end wall side (22).
2. 2. Turbine vane film hole structure according to claim 1, characterized in that the cross section of the expanded section cold air channel (12) is racetrack-shaped with a width equal to the diameter of the cylindrical section cold air channel (11) on a cross section perpendicular to the depth direction of the film hole (1).
3. 3. The turbine vane film hole structure as claimed in claim 2, wherein the opening of the expansion section cold air channel (12) on the cooled surface is the same shape and size as the opening of the existing standard spanwise symmetric channel on the cooled surface.
4. 4. A turbine vane film hole structure according to claim 3, characterized in that on a projection plane parallel to the cooled surface, the angle between the projection of the side wall of the expansion section cold air passage (12) near the end wall and the projection of the center line of the film hole (1) is beta 1 , the angle between the projection of the side wall on the other side and the projection of the center line of the film hole (1) is beta 2 , satisfying that 0 ° -beta 2 ＜β 1 -40 °, and 10 ° -beta 2 +β 1 -40 °.
5. 5. Turbine vane film hole structure according to claim 3 or 4, characterized in that the length of the long side of the opening of the expansion section cold air channel (12) on the cooled surface is 1-5 times the diameter of the cylinder section cold air channel (11).
6. 6. A turbine vane film hole structure according to claim 3, characterized in that the angle between the centre line of the film hole (1) and the cooled surface is 30 ° -60 °.
7. 7. Turbine vane film hole structure according to claim 1, characterized in that the total length of the film hole (1) is 4-8 times the diameter of the cylindrical section cold air channel (11).
8. 8. Turbine vane film hole structure according to claim 1, characterized in that the total length of the film hole (1) is 2-4 times the length of the cylindrical section cold air channel (11).
9. 9. Turbine vane film hole structure according to claim 1, characterized in that the diameter of the cross section of the cylindrical section cold air channel (11) is 0.3-3 mm on a cross section perpendicular to the depth direction of the film hole (1).
10. 10. Turbine vane, characterized in that it comprises a vane body (21), said vane body (21) having a suction side and a pressure side, both of which are provided with the turbine vane film hole structure according to any one of claims 1-9.

Description

Turbine guide vane air film hole structure and turbine guide vane Technical Field The invention relates to the technical field of aeroengines, in particular to a turbine guide vane air film hole structure and a turbine guide vane. Background In the prior art, a turbine of a gas turbine engine widely uses a film cooling technology to ensure that the turbine cannot overheat, and the basic principle is that cooling gas is sprayed out through film cooling holes on blades and covers the surfaces of the blades, so that metal blades and high-temperature gas are isolated, and blade ablation is avoided. When the turbine guide vanes rotate, the front edge cuts air at a high speed and forms horseshoe vortices at two sides, after suction surface branches of the horseshoe vortices at the front edge are intersected with pressure surface branches of adjacent blades, the pressure surface branches migrate from the pressure surface to the suction surface under the action of circumferential pressure gradient, low-energy fluid in boundary layers is continuously sucked, and finally a pair of channel vortices with opposite directions are formed in blade channels between two adjacent turbine guide vanes. The channel vortices in the region of the turbine vane near the end wall provide shear forces on the suction side in the direction of the blade such that the wall polar restrictor line is offset into the blade. For suction surface air film cooling, the channel vortex suction effect enables the air film jet flow at the near end area of the blade to deviate towards the middle direction of the blade, and the wind-suction cold air leaves the wall surface, so that the cold air is accumulated in She Zhongou areas to generate waste, triangular areas which are not covered by the air film are formed on the end walls at the two sides of the turbine guide blade, and the triangular areas are not cooled for short, so that the air film cooling effect is reduced in the near end wall area of the blade, and the problem of overtemperature is easy to occur. In the prior art, the uncooled triangular region problem is solved by adopting the air film hole with the compound angle, but the scheme has the following problems that firstly, in the area of the near end wall of the blade, the processing of the air film hole is limited due to the existence of the upper end wall and the lower end wall, and the inclined hole with the compound angle is difficult to punch. Secondly, because the length of the air film Kong Zhan with the composite angle is larger, the air film needs to occupy larger blade expanding space, thereby influencing the number, the positions and the arrangement of the air film holes of the blades. Thirdly, the composite angle can change geometric parameters such as the length-diameter ratio of the air film hole, the outlet area and the like, so that the selection of geometric parameters of the air film Kong Zuiyou is affected. Finally, for low aspect ratio blades, the number of film holes is limited, thus requiring a larger coverage area per film hole. Therefore, there is a need to design a turbine vane gas film hole structure and a turbine vane to solve the above problems. Disclosure of Invention The invention aims to provide a turbine guide vane air film hole structure which is simple to process and can reduce the area of an uncooled triangular region. The turbine guide vane air film hole structure comprises at least one air film hole, wherein the air film hole comprises a cylindrical section air cooling channel and an expansion section air cooling channel which incline along the same direction, the cylindrical section air cooling channel is communicated with the expansion section air cooling channel, the cross section of the expansion section air cooling channel is in a symmetrical pattern on the cross section perpendicular to the depth direction of the air film hole, and the symmetrical center of the cross section of the expansion section air cooling channel is positioned between the center of the cross section of the cylindrical section air cooling channel and the end wall side. Preferably, the cross section of the expansion section cold air passage is in a racetrack shape with a width equal to the diameter of the cylindrical section cold air passage on a cross section perpendicular to the depth direction of the air film hole. Preferably, the opening of the expansion section cold air channel on the cooled surface is the same as the opening of the existing standard spanwise symmetric channel on the cooled surface in shape and size. Preferably, on a projection plane parallel to the cooled surface, an angle between a projection of a side wall of the expansion section cold air passage close to the end wall and a projection of a center line of the air film hole is beta 1, and an angle between a projection of a side wall of the other side and a projection of a center line of the air film hole is beta 2, and the angle satisfies that beta 2＜β1