CN-121993262-A - Air-cooled turbine curved blade and design method thereof

CN121993262ACN 121993262 ACN121993262 ACN 121993262ACN-121993262-A

Abstract

The application provides an air-cooled turbine bent blade and a design method thereof, and relates to the technical field of aeroengines and gas turbines, wherein the bent blade comprises a plurality of blade profile sections which are sequentially overlapped, and the gravity centers of the blade profile sections form an overlapping line of the bent blade; wherein the stacking line is configured as a C-arc, and the center of gravity of a third blade profile section positioned at the center of the plurality of blade profile sections is horizontally offset towards the pressure surface side by a first distance relative to the center of gravity of a first blade profile section positioned at the blade root, and the center of gravity of a second blade profile section positioned at the blade tip is horizontally offset towards the suction surface side by a second distance relative to the center of gravity of the first blade profile section.

Inventors

ZHANG XIAODONG
LI CHEN
ZHANG ZHIXIN
XU QINGZONG
WANG SHANYOU

Assignees

中国科学院工程热物理研究所

Dates

Publication Date: 20260508
Application Date: 20260318

Claims (10)

1. An air-cooled turbine curved blade, characterized in that the curved blade comprises a plurality of blade profile sections which are sequentially overlapped, and the gravity centers of the plurality of blade profile sections form an overlapped line of the curved blade; Wherein the stacking line is configured as a C-shaped arc line, and the center of gravity of a third blade profile section positioned at the center of the blade profile sections is horizontally offset towards the pressure surface side by a first distance relative to the center of gravity of a first blade profile section positioned at the blade root, and the center of gravity of a second blade profile section positioned at the blade tip is horizontally offset towards the suction surface side by a second distance relative to the center of gravity of the first blade profile section.
2. The bent blade according to claim 1, wherein a vertical distance between a center of gravity of the first blade profile section and a center of gravity of the second blade profile section is a third distance, and a ratio of the first distance to the third distance ranges from 0.05 to 0.1.
3. The bent blade according to claim 2, wherein the ratio of the second distance to the third distance is in the range of 0.03-0.15.
4. The curved blade of claim 1, wherein the chord length of a plurality of said airfoil sections increases progressively from said root to tip.
5. A curved blade according to claim 1, wherein the root of the curved blade is provided with a root fillet, and the radius of curvature of the root fillet decreases gradually from the leading edge of the profiled section to the trailing edge of the profiled section.
6. The bent blade according to claim 5, wherein the radius of curvature of the root fillet at the leading edge of the root is 1.5-2.5 times the radius of curvature of the root fillet at the trailing edge of the root.
7. A method of designing an air cooled turbine bucket, the bucket comprising a plurality of airfoil sections stacked in sequence, the method comprising: determining a first stacking point position of a first blade profile section positioned at a blade root; Determining a second stacking point position of a second blade profile section positioned at the blade tip based on the first stacking point position and a first preset distance, wherein the first preset distance represents a preset distance for horizontally shifting the second stacking point position towards the suction surface side relative to the first stacking point position; determining a third stacking point position of a third blade-shaped section positioned at the center based on the first stacking point position and a second preset distance, wherein the second preset distance represents a preset distance for horizontally shifting the third stacking point position towards the pressure surface side relative to the first stacking point position; determining a stacking line of the bent blade based on the first stacking point position, the second stacking point position, and the third stacking point position; And stacking a plurality of blade profile sections based on the stacking line to obtain the bent blade.
8. The method of claim 7, wherein stacking a plurality of the profiled sections based on the stacking line to obtain the bent blade comprises: Determining a target offset of the center of gravity of the blade profile section at each radial height based on the initial position of the center of gravity of the blade profile section at each radial height and a target position of the stacking line at a corresponding height; and translating the blade profile sections of each radial height based on the target offset of the gravity centers of the blade profile sections of each radial height, so that the gravity centers of the blade profile sections of each radial height are positioned on the stacking line, and obtaining the bent blade.
9. The method of claim 7, wherein a vertical distance between the first stacking point position and the second stacking point position is a third distance; The ratio range of the first preset distance to the third distance is 0.03-0.15; the ratio of the second preset distance to the third distance ranges from 0.05 to 0.1.
10. The method of claim 7, wherein the method further comprises: Determining a meridional flow channel based on the dimensional parameters of the upper and lower rim plates, wherein the width of the upper rim plate is greater than the width of the lower rim plate; And generating a plurality of blade profile sections with different radial heights by taking the meridian flow passage as a constraint boundary.

Description

Air-cooled turbine curved blade and design method thereof Technical Field The application relates to the technical field of aeroengines and gas turbines, in particular to an air-cooled turbine bent blade and a design method of the air-cooled turbine bent blade. Background Turbine bending blade technology is one of the core technologies of modern high performance gas turbine and aeroengine turbine designs, the core goal of which is to reconstruct three-dimensional flow within a flow channel by optimizing the three-dimensional spatial configuration of the blades. The degree of freedom in designing the curved shape of a conventional cooling-free blade is high. However, for air-cooled turbine blades, in particular guide blades of the insert-type cooling structure, the three-dimensional design thereof not only requires consideration of the aerodynamic properties, but also must be compatible with the assemblability of the inner cooling insert. The overly complex curved shape may result in a non-smooth flow path through the cavity, increasing the difficulty of manufacturing and assembling the cooling insert. Disclosure of Invention In view of this, the present application provides an air-cooled turbine curved blade and a method of designing an air-cooled turbine curved blade. An aspect of the application provides a turbine curved blade, which comprises a plurality of blade profile sections which are sequentially overlapped, wherein the gravity centers of the plurality of blade profile sections form an overlapped line of the curved blade, the overlapped line is configured into a C-shaped arc line, the gravity center of a third blade profile section positioned at the center of the plurality of blade profile sections is horizontally offset towards a pressure surface side by a first distance relative to the gravity center of a first blade profile section positioned at a blade root, and the gravity center of a second blade profile section positioned at a blade tip is horizontally offset towards a suction surface side by a second distance relative to the gravity center of the first blade profile section. According to the embodiment of the application, the vertical distance between the center of gravity of the first blade profile section and the center of gravity of the second blade profile section is a third distance, and the ratio of the first distance to the third distance is in the range of 0.05-0.1. According to the embodiment of the application, the ratio of the second distance to the third distance is in the range of 0.03-0.15. According to an embodiment of the application, the chord length of the plurality of profiled sections increases gradually from the blade root to the blade tip, the chord length being the linear distance between the leading edge of the profiled section and the trailing edge of the profiled section. According to an embodiment of the application, the blade root of the curved blade is provided with a blade root fillet, and the radius of curvature of the blade root fillet gradually decreases from the leading edge of the profiled section to the trailing edge of the profiled section. According to the embodiment of the application, the curvature radius of the blade root fillet at the front edge of the blade root is 1.5-2.5 times of the curvature radius of the blade root fillet at the rear edge of the blade root. The application provides a design method of a turbine curved blade, which comprises a plurality of sequentially overlapped blade profile sections, wherein the method comprises the steps of determining a first stacking point position of a first blade profile section positioned at a blade root, determining a second stacking point position of a second blade profile section positioned at a blade top based on the first stacking point position and the first preset distance, wherein the first preset distance represents a preset distance that the second stacking point position horizontally deviates towards a suction surface side relative to the first stacking point position, determining a third stacking point position of a third blade profile section positioned at the center based on the first stacking point position and the second preset distance, wherein the second preset distance represents a preset distance that the third stacking point position horizontally deviates towards a pressure surface side relative to the first stacking point position, determining a stacking line of the curved blade based on the first stacking point position, the second stacking point position and the third stacking point position, and obtaining the curved blade based on the stacking line. According to the embodiment of the application, a plurality of blade profile sections are stacked based on stacking lines to obtain a bent blade, wherein the method comprises the steps of determining target offset of the gravity centers of the blade profile sections with radial heights based on initial positions of the gravity center