Internal cooling structure for tail edge of turbine moving blade of gas turbine

Abstract

The utility model provides a gas turbine rotor blade trailing edge internal cooling structure, and belongs to the technical field of gas turbine turbines. The problem of how to efficiently cool the tail edge of the turbine moving blade of the gas turbine is solved. The blade comprises a wedge-shaped part and a horizontal part, the wedge-shaped part and the horizontal part are communicated to form a wedge-shaped channel, a column rib cooling structure longitudinally penetrates through the interior of the wedge-shaped part, and the wedge-shaped part starts from the left side edge of an inlet of the blade tail edge cooling channel to the right side edge of the column rib cooling structure. A pit cooling structure is arranged on the bottom wall of the cooling channel in the tail edge of the turbine moving blade of the wedge-shaped part, and a plurality of flow dividing columns are arranged in the horizontal part. The combination of the column rib cooling structures and the pit cooling structures can form a stronger heat exchange effect, and the cooling capacity of the inner cavity of the trailing edge can be remarkably improved by additionally arranging the multiple rows of pit cooling structures between the column rib cooling structure arrays.

Description

Technical Field

[0001] The utility model belongs to the technical field of gas turbine turbines, in particular to an internal cooling structure of a gas turbine turbine blade trailing edge with a wedge-shaped turning channel combined with a concave pit and column ribs. Background Art

[0002] One of the main research directions of gas turbines is to increase the initial temperature of the gas and thus improve the efficiency of the gas turbine. In order to allow the turbine blades to operate normally at the highest possible initial temperature, they must be cooled.

[0003] Many domestic scholars have conducted extensive research on straight channels, including the arrangement, spacing, shape, and height of the ribs, as well as the addition of concave and convex structures. In typical blade trailing edge cooling channel designs, cooling air enters the internal channel radially, rotates 90°, and ultimately exits through the transverse trailing edge return groove. This zigzag channel is a typical feature of turbine blade trailing edge cooling channels. Therefore, the present invention improves the internal cooling structure of the zigzag channel at the trailing edge. Utility Model Content

[0004] In view of this, in order to solve the problem of how to efficiently cool the trailing edge of a gas turbine turbine blade, the utility model proposes an internal cooling structure of the trailing edge of a gas turbine turbine blade, which has a wedge-shaped turning channel with column ribs and a recess.

[0005] To achieve the above-mentioned purpose, the present invention adopts the following technical solution: an internal cooling structure of the trailing edge of a gas turbine turbine blade, which has a wedge-shaped turning channel with column ribs and a pit, comprising a wedge-shaped portion and a horizontal portion, wherein the wedge-shaped portion and the horizontal portion are connected to form a wedge-shaped channel, and a column rib cooling structure is longitudinally penetrated in the wedge-shaped portion, the wedge-shaped portion starts from the left side of the entrance of the blade trailing edge cooling channel and extends to the right side of the column rib cooling structure, a pit cooling structure is provided on the bottom wall of the internal cooling channel of the trailing edge of the turbine blade in the wedge-shaped portion, and a plurality of diverter columns are provided in the horizontal portion.

[0006] Furthermore, the cooling air enters the blade trailing edge cooling channel inlet radially, and rotates 90 degrees to pass through the column rib cooling structure and the pit cooling structure and then through the diverter column, and finally flows out from the blade trailing edge cooling channel outlet at the tail end of the horizontal part.

[0007] Furthermore, the column rib cooling structure includes a plurality of rows of column rib structures, and each row of column rib structures includes a plurality of column ribs.

[0008] Furthermore, the pit cooling structure includes several rows of pit structures, and each row of pit structures includes several pits.

[0009] Furthermore, the pit structures and the column rib structures are located in the same row, and the column ribs and the pits are arranged alternately.

[0010] Furthermore, the diameter of the column rib is 10 mm, the number of rows of the column rib cooling structure is 4, and they are arranged in a cross manner, with the row spacing and column spacing both being 25 mm.

[0011] Furthermore, each pit has a height H of 3 mm and a diameter D of 8 mm.

[0012] Furthermore, the cross section of the column rib is circular, elliptical or teardrop-shaped.

[0013] Furthermore, the included angle of the wedge-shaped channel is 10°, the height of the left side of the inlet of the cooling channel at the trailing edge of the blade is 42.2 mm, and the height of the horizontal portion is 10.5 mm.

[0014] Furthermore, the wedge-shaped portion includes a channel portion and a vertical portion, the channel portion and the vertical portion are perpendicular to each other, the starting end of the channel portion is the entrance of the cooling channel at the trailing edge of the blade, and the shape of the wedge-shaped portion is like a flag with a high left side and a low right side, and then the vertical portion is connected to the horizontal portion, and the height of the horizontal portion remains unchanged.

[0015] Compared with the prior art, the internal cooling structure of the trailing edge of a gas turbine rotor blade with a wedge-shaped turning channel and a recess with column ribs described in the present invention has the following beneficial effects:

[0016] 1. The present invention adopts a combination of column rib cooling structure and pit cooling structure to form a stronger heat exchange effect. By adding multiple rows of pit cooling structures between the column rib cooling structure array, the cooling capacity of the trailing edge cavity can be significantly improved.

[0017] 2. In the present invention, while cooling air consumption is reduced, the combination of the column ribs and the pit structure improves the overall heat exchange efficiency and increases the service life of the turbine. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The accompanying drawings, which constitute part of the present invention, are intended to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are intended to explain the present invention and do not constitute an improper limitation of the present invention. In the accompanying drawings:

[0019] Figure 1 This is a schematic diagram of the structure of the trailing edge of a gas turbine rotor blade;

[0020] Figure 2 This is a schematic structural diagram of the internal cooling structure of the trailing edge of a gas turbine rotor blade with a wedge-shaped turning channel with column ribs combined with a recess according to the present invention;

[0021] Figure 3 The main view and dimension marking of the internal cooling structure of the turbine blade trailing edge;

[0022] Figure 4 Schematic diagram of the wedge channel angle α;

[0023] Figure 5 Schematic diagram of the column rib and pit structure, where the solid part is the pit and the hollow part is the column rib;

[0024] Figure 6 is a schematic diagram of the structure of the pit;

[0025] Figure 7 The Nusselt number changes of the original bottom wall and the one with the pit structure under different Reynolds numbers;

[0026] Figure 8 This is the change diagram of comprehensive heat transfer efficiency of the original bottom wall and the one with the pit structure under different Reynolds numbers;

[0027] In the figure: 1-blade trailing edge cooling channel inlet, 2-blade trailing edge cooling channel outlet, 3-column rib cooling structure, 4-pit cooling structure, 5-bottom wall of the internal cooling channel at the trailing edge of the turbine blade, 6-diverter column, 7-wedge-shaped channel, 8-column rib, 9-pit. DETAILED DESCRIPTION

[0028] The following will be combined with the accompanying drawings in the embodiments of the present invention to clearly and completely explain the technical solutions in the embodiments of the present invention. It should be noted that the embodiments and features in the embodiments of the present invention can be combined with each other in the absence of conflict, and the embodiments described are only part of the embodiments of the present invention, not all of the embodiments.

[0029] See also Figure 1-8 This embodiment describes an internal cooling structure of the trailing edge of a gas turbine turbine blade having a wedge-shaped turning channel with column ribs combined with a recess. The main improved structure includes a column rib cooling structure 3 and a recess cooling structure 4. The cooling gas enters from the cooling channel inlet 1 of the blade trailing edge, turns 90 degrees, passes through the column rib cooling structure 3 and the recess cooling structure 4, and then passes through the diverter column 6, and flows out from the cooling channel outlet 2 of the blade trailing edge.

[0030] A pit cooling structure 4 is added to the bottom wall 5 of the cooling channel inside the trailing edge of the turbine blade. The diameter of the column rib 8 is 10 mm, the number of the column rib rows is 4, and they are arranged in a cross-wise manner. The row spacing and column spacing are both 25 mm. Figure 5 shown.

[0031] The bottom wall 5 of the internal cooling channel at the trailing edge of the turbine blade has an area of ​​300×105mm. The bottom wall 5 of the internal cooling channel at the trailing edge of the turbine blade starts 15mm to the right of the right side of the cooling channel inlet 1 at the trailing edge of the blade and ends at the left side of the horizontal part. It is 105mm long and the horizontal length is 256.5mm. Figure 3 shown.

[0032] The included angle of the wedge-shaped channel 7 is 10°, the height of the left side of the blade trailing edge cooling channel inlet 1 is 42.2 mm, and the height of the horizontal part is 10.5 mm.

[0033] In the dimple cooling structure 4 , the height H of each dimple 9 is 3 mm, and the diameter D of the dimple 9 is 8 mm.

[0034] The cross section of the column rib 8 of the column rib cooling structure 3 can be circular, or can be replaced with other geometric shapes (elliptical, teardrop-shaped, etc.), mainly by adding pits 9 in the gaps between the column ribs 8 and arranging them alternately.

[0035] The Nusselt number is used to characterize the strength of convective heat transfer. When the Reynolds number is 2w, 4w, 6w, 8w, and 10w, the surface average Nusselt number of the normal bottom wall is 147.06, 208.21, 265.13, 317.30, and 366.87, respectively. After adding the pit structure, the surface average Nusselt number becomes 168.24, 238.02, 300.80, 357.89, and 409.27, which are increased by 14.4%, 14.3%, 13.5%, 12.8%, and 11.6%, respectively (e.g. Figure 7 The comprehensive heat exchange efficiency increased from the original 79%, 66%, 61%, 58%, 55% to 88%, 71%, 64%, 60%, 56% (as shown). Figure 8 shown).

[0036] The working principle of the internal cooling structure of the gas turbine turbine blade trailing edge with the wedge-shaped turning channel with column ribs and the recessed pit is as follows:

[0037] The column-rib cooling structure 3 enhances heat transfer by increasing the heat exchange area and increasing the turbulent energy of the cooling airflow. The presence of the column-rib cooling structure 3 at the trailing edge increases airflow disturbance, forming a trailing-edge vortex. This helps accelerate the separation of the boundary layer on the turbine blade's internal wall, further improving heat transfer efficiency.

[0038] The dimple cooling structure 4 enhances local heat transfer by generating eddies on the wall surface. The combined rib cooling structure 3 and dimple cooling structure 4 leverage the respective advantages of the ribs and dimples to achieve more efficient heat exchange. By optimizing flow and heat transfer characteristics, the combined rib cooling structure 3 and dimple cooling structure 4 improves turbine blade cooling efficiency while maintaining low coolant consumption. This combined technology provides an effective cooling strategy for turbine blade design.

[0039] The embodiments of the present invention disclosed above are intended only to illustrate the present invention. These embodiments do not exhaust all details, nor do they limit the present invention to the specific embodiments described. Numerous modifications and variations are possible based on the contents of this specification. These embodiments are selected and described in detail in this specification to better explain the principles and practical applications of the present invention, thereby enabling those skilled in the art to better understand and utilize the present invention.

Claims

1. A gas turbine turbine blade trailing edge internal cooling structure, characterized by: The invention comprises a wedge-shaped portion and a horizontal portion, wherein the wedge-shaped portion and the horizontal portion are connected to form a wedge-shaped channel (7), a column rib cooling structure (3) is longitudinally penetrated in the wedge-shaped portion, the wedge-shaped portion starts from the left side of the cooling channel inlet (1) of the blade trailing edge and extends to the right side of the column rib cooling structure (3), a pit cooling structure (4) is provided on the bottom wall (5) of the cooling channel inside the turbine blade trailing edge of the wedge-shaped portion, and a plurality of diverter columns (6) are provided in the horizontal portion.

2. The internal cooling structure for the trailing edge of a gas turbine rotor blade according to claim 1, characterized in that: The wedge-shaped portion comprises a channel portion and a vertical portion, the channel portion and the vertical portion are perpendicular to each other, and the starting end of the channel portion is the blade trailing edge cooling channel inlet (1).

3. The internal cooling structure for the trailing edge of a gas turbine rotor blade according to claim 2, characterized in that: The cooling air enters the blade trailing edge cooling channel inlet (1) from the radial direction, and after rotating 90 degrees, passes through the column rib cooling structure (3) and the pit cooling structure (4), and then passes through the diverter column (6), and finally flows out from the blade trailing edge cooling channel outlet (2) at the tail end of the horizontal part.

4. The internal cooling structure for the trailing edge of a gas turbine rotor blade according to claim 1, 2 or 3, characterized in that: The column rib cooling structure (3) comprises a plurality of rows of column rib structures, and each row of column rib structures comprises a plurality of column ribs (8).

5. The internal cooling structure for the trailing edge of a gas turbine rotor blade according to claim 4, characterized in that: The pit cooling structure (4) comprises a plurality of rows of pit structures, and each row of pit structures comprises a plurality of pits (9).

6. The internal cooling structure for the trailing edge of a gas turbine rotor blade according to claim 5, characterized in that: The pit structure and the column rib structure are located in the same row, and the column ribs (8) and the pits (9) are arranged alternately.

7. The internal cooling structure for the trailing edge of a gas turbine rotor blade according to claim 6, characterized in that: The column rib (8) has a diameter of 10 mm, and the column rib cooling structure (3) has 4 rows, arranged in a cross-arrangement manner, with both the row spacing and column spacing being 25 mm.

8. The internal cooling structure for the trailing edge of a gas turbine rotor blade according to claim 6, characterized in that: The height H of each pit (9) is 3 mm, and the diameter D of the pit (9) is 8 mm.

9. The internal cooling structure for the trailing edge of a gas turbine rotor blade according to claim 6, characterized in that: The cross section of the column rib (8) is circular, elliptical or teardrop-shaped.

10. The internal cooling structure for the trailing edge of a gas turbine rotor blade according to claim 1, characterized in that: The included angle of the wedge-shaped channel (7) is 10°, the height of the left side of the blade trailing edge cooling channel inlet (1) is 42.2 mm, and the height of the horizontal part is 10.5 mm.

Images