Turbine blade with a combination of a trip post and a streamwise trip rib cooling structure

Abstract

The application discloses a kind of turbulence column and flow direction turbulence rib combination cooling structure for turbine blade, belong to turbine blade cooling technical field;The structure includes upper wall surface, lower wall surface, multiple turbulence columns and two groups of turbulence ribs;Multiple turbulence columns array arrangement and are fixed between upper and lower wall surface;Two groups of turbulence ribs are symmetrically arranged in upper and lower wall surface, and turbulence rib unit of same group is spaced along the direction of development, and it is alternately arranged along the direction of flow with turbulence column.Turbulence rib unit is the arc tapering type flow guide structure that is opened to the direction of airflow incoming flow, located at the leeward side of turbulence column, and the inside wall surface profile is constructed using cubic polynomial aerodynamic curve, to form smooth tapering flow guide channel.Compared with prior art, the channel flow resistance of the application is reduced by 5.86% to 32.85%, the comprehensive thermal performance factor is improved by 3.24% to 6.65%, and the wall surface heat exchange uniformity is significantly improved, suitable for high-efficiency cooling of turbine blades of aeroengine and gas turbine.

Description

Technical Field

[0001] This invention belongs to the field of turbine blade cooling technology, specifically relating to a combined cooling structure of a turbulence column and a flow direction turbulence rib for turbine blades. Background Technology

[0002] In pursuit of higher thrust and thermal efficiency, the turbine inlet gas temperature in gas turbine engines continuously rises, posing a significant challenge to the normal operation of turbine blades. Current advanced gas turbine engines have turbine inlet gas temperatures exceeding 2000K, far surpassing the temperature resistance limit of turbine blade materials. Therefore, highly efficient cooling technologies must be employed to ensure the proper functioning of the blades.

[0003] Currently, turbine blades primarily employ a combination of internal and external cooling. External cooling involves adding film cooling holes to create a cool gas protective film between the blade wall and the high-temperature combustion gases, isolating heat transfer between them. Internal cooling achieves temperature reduction by increasing the heat transfer coefficient of the internal blades. However, due to the small size of the blades, the cooling structure design must balance heat transfer performance and blade strength. Turbine column cooling is a promising approach. On one hand, the turbulence enhances the turbulence of the cooling airflow inside the blade, thereby strengthening heat transfer to the blade wall. On the other hand, the turbulence column structure provides good structural support and connection for hollow blades, ensuring blade strength to a certain extent.

[0004] The turbulence column cooling structure is a typical heat transfer enhancement structure applied inside turbine blades. Previous studies have systematically obtained the flow structure and heat transfer characteristics of turbulence column structures applied inside turbine blades and confirmed their excellent heat transfer enhancement capabilities. However, there is still room for further improvement in the performance of turbulence column structures. Due to flow instability, the cold air flow rate in the channel is unevenly distributed along the spanwise direction, with the cold air flow rate near the sidewall being greater than that at the center of the channel. Furthermore, as the airflow develops further in the channel, the unevenness of the flow rate distribution gradually intensifies. Affected by the uneven distribution of the cold air flow rate, the heat transfer distribution characteristics on the wall also exhibit an uneven distribution pattern, with lower values ​​in the middle and higher values ​​on both sides. Summary of the Invention

[0005] The technical problem to be solved: To overcome the shortcomings of existing technologies, this invention provides a combined cooling structure of a baffle column and flow-directing baffle ribs for turbine blades. The arc-shaped funnel ribs directly guide airflow to impact the leeward region, enhancing local heat transfer. The arc-shaped transition design reduces airflow separation and pressure loss, and improves the unevenness of traditional baffle column structures, which are characterized by a low center and high sides. This invention effectively guides the high-speed mainstream flow to impact the low-speed wake region on the leeward side of the baffle column with minimal flow resistance, improving the leeward side heat transfer capacity and simultaneously enhancing the uniformity of heat transfer on the wall surface.

[0006] The technical solution of the present invention is: a combined cooling structure of turbulence columns and flow direction turbulence ribs for turbine blades, including an upper wall and a lower wall forming a cooling airflow channel, and a plurality of turbulence columns and two sets of turbulence ribs disposed in the channel; each set of turbulence ribs includes several turbulence rib units; The multiple turbulence columns are arranged in an array and fixedly connected between the upper and lower walls to turbulent airflow and enhance wall heat exchange. The two sets of turbulence ribs are symmetrically arranged on the upper and lower walls, respectively. The turbulence column and the turbulence rib unit located downstream of it constitute a turbulence group. Each turbulence group is arranged at intervals along the direction perpendicular to the flow direction; and they are arranged in a cross pattern along the flow direction. The rib unit is constructed as an arc-shaped tapering guide structure with an opening facing the direction of airflow. Each rib unit is respectively set on the leeward side of each rib, forming a guide channel for collecting, accelerating and reorienting the high-speed main flow that bypasses the rib. The high-speed main flow that bypasses the upstream rib is smoothly guided to the leeward side region of the downstream adjacent rib, so as to compress and accelerate the low-speed wake region airflow on the leeward side.

[0007] A further technical solution of the present invention is: the inner wall surface of the turbulence rib unit is an aerodynamically optimized smooth curved surface, and its contour line satisfies a cubic polynomial curve equation. A local coordinate system is established with the center of the outlet section of the turbulence rib unit as the origin and the reverse flow direction as the positive X-axis. The curve equation y(x) of the inner wall surface satisfies:

[0008] Where y(x) is the vertical distance from the inner wall surface of the rib unit to its central axis; L is the flow length of the rib unit; W half_out W is half the width at the outlet of the spoiler rib unit. half_in This is half the width at the inlet of the friction rib unit; A and B are shape coefficients, determined by the boundary conditions:

[0009]

[0010] The equation of the curve satisfies the derivative y'(L) = 0 at the entrance.

[0011] A further technical solution of the present invention is: the turbulence rib unit includes two symmetrically arranged concave arc ribs in the shape of a funnel, wherein the large-diameter end of the funnel is the inlet of the turbulence rib unit and the small-diameter end is the outlet of the turbulence rib unit; the radius R of the concave arc and the diameter D of the turbulence column satisfy: R=0.8D~1.2D.

[0012] A further technical solution of the present invention is: the center of a single rib of the turbulence rib unit is located on the perpendicular bisector of the line connecting the centers of two spanwise adjacent turbulence columns upstream of the turbulence rib unit, and the flow distance I between the center of a single rib and the connecting line satisfies: I = 0.6D ~ 1.5D.

[0013] A further technical solution of the present invention is: the height H1 of the turbulence column is 1D to 3D; The flow direction spacing S between the axes of two adjacent turbulence columns x =5D; The spanwise spacing S between two adjacent spoiler columns arranged along the spanwise direction y =2.5D; The number of rows of the turbulence-disrupting columns is 3 to 11 in the spanwise direction and 3 to 11 in the flowwise direction.

[0014] A further technical solution of the present invention is: the height H2 of the turbulence rib unit is 0.25D to 0.5D, and its rib thickness W is 0.05D to 0.3D.

[0015] A further technical solution of the present invention is: the flow-guiding channel is formed by two ribs in the flow-guiding rib unit, the outlet width of the flow-guiding channel is B < D, and the flow-guiding channel is symmetrically arranged about the axis of its upstream flow-guiding column.

[0016] A design method for a combined cooling structure of baffle columns and flow-direction baffles for turbine blades includes the following steps: Step 1: Determine the parameters of the turbulence column array; Based on the cooling requirements of the turbine blade trailing edge, determine the diameter D of the turbulence column and set the flow direction spacing S. x =5D and spanning distance S y =2.5D, and the spoiler columns are arranged in a staggered manner to form a spoiler column array; Step 2: Determine the placement of the two sets of spoiler ribs; Two sets of ribs are symmetrically arranged on the upper and lower walls, respectively. An arc-shaped funnel-shaped rib unit is set on the leeward side of each turbulence column, so that the opening of the rib unit faces the direction of the airflow. Step 3: Construct the aerodynamic surface of the fringe rib unit; The inner wall profile of the turbulence rib is designed based on the cubic polynomial curve equation. A local coordinate system is established with the center of the outlet section of the turbulence rib unit as the origin and the counter-current direction as the positive X-axis. The parameters L and W in the curve equation are then determined. half_out W half_in And calculate coefficients A and B to make the curve satisfy the derivative y'(L) = 0 at the inlet, ensuring that the airflow enters in parallel without impact loss and the flow channel cross-sectional area transitions smoothly; Step 4: Determine the geometric parameters of the spoiler rib unit; The height H2 of the friction rib unit is set to 0.25D~0.5D, the rib thickness W=0.05D~0.3D, the radius R=0.8D~1.2D, and the flow distance I between the center of the friction rib and the line connecting the upstream friction column is set to 0.6D~1.5D. Step 5: Form a cross-shaped cooling structure; Two sets of turbulence ribs are arrayed on the upper and lower walls respectively. The turbulence column and the turbulence rib unit located downstream of it constitute a turbulence group. Each turbulence group is arranged at intervals in a direction perpendicular to the flow direction; and they are arranged in a cross pattern along the flow direction.

[0017] A turbine blade includes a combined cooling structure of a turbulence column and a flow-direction turbulence rib, designed by the aforementioned design method.

[0018] Beneficial effects The beneficial effects of this invention are as follows: This invention can effectively guide the cooling airflow to the leeward side of the turbulence column through the guiding effect of the turbulence ribs, improving the problem of weak heat exchange capacity on the leeward side of traditional turbulence columns. At the same time, it increases the heat exchange area and improves the heat exchange uniformity of the upper and lower walls. Specific effects are analyzed as follows: 1. This invention employs an arc-shaped funnel-shaped rib with an opening facing the wind. By utilizing the "nozzle effect" of the gradually narrowing flow channel, the high-speed mainstream flowing around the turbulence column is smoothly guided to the leeward side, compressing and accelerating the airflow in the low-speed wake region. This achieves active scouring of the leeward area and fundamentally solves the technical problems of weak heat exchange capacity and easy formation of local hot spots on the leeward side of traditional turbulence column structures.

[0019] 2. This invention guides airflow to a uniform distribution along the spanwise direction through the cross-arrangement of the turbulence-distributing ribs, balancing the heat transfer intensity between the windward and leeward sides of the turbulence-distributing columns, eliminating the temperature gradient in traditional structures, effectively reducing blade thermal stress, and extending the service life of turbine blades. The turbulence-distributing ribs further enhance fluid mixing near the wall, increasing near-wall turbulence and thus strengthening heat transfer between the upper and lower walls. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the combined cooling structure of the turbulence column and flow direction turbulence rib for turbine blades in an embodiment of the present invention; Figure 2 This is a partially enlarged schematic diagram of the combined cooling structure of the turbulence column and flow direction turbulence rib for turbine blades in an embodiment of the present invention; Figure 3 This is a schematic diagram illustrating the arrangement of the baffle columns and baffle ribs in an embodiment of the present invention; Figure 4 This is a top view showing the positional relationship between the baffle column and the baffle rib in an embodiment of the present invention; Figure 5 This is a cross-sectional view showing the positional relationship between the baffle column and the baffle rib in an embodiment of the present invention; Figure 6 The vortex cloud diagrams for Example 1 and Comparative Example 1 are shown below. Figure 7 The average Nusselt number distribution cloud map of the wall surface of a conventional staggered turbulence column structure when the dimensionless cold air flow rate Re=25000; Figure 8 When the dimensionless cold air flow rate Re=25000, the average Nusselt number distribution cloud map of the wall surface of the combined cooling structure of the turbulence column and flow direction turbulence rib used for turbine blades in Examples 1 and 2 is applied. Figure 9 Temperature distribution cloud diagrams of cross sections of the application embodiment 1 and the traditional cross-bracing turbulence column structure; Figure 10 The graphs show the average Nusselt number curves of the surface flow direction of the wall surface in Examples 1 and 2 and the traditional cross-row turbulence column structure. Figure 11 The graphs show the spanwise average Nusselt number curves of the wall surface of the application examples 1 and 2 and the traditional cross-row turbulence-disrupting column structure; Figure 12 The ratio of channel flow resistance to smooth pipe flow resistance is used in Examples 1 and 2 and Comparative Examples 1 and 2. f / f 0 bar chart; Figure 13 The overall heat transfer capacity (TPF) of the channels in Application Examples 1 and 2 and Comparative Examples 1 and 2 is shown in the bar chart. Explanation of reference numerals in the attached diagram: 1-Breakthrough column, 2-Upper wall surface, 3-Lower wall surface, 4-Breakthrough rib unit. Detailed Implementation

[0021] The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the invention, and should not be construed as limiting the invention.

[0022] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0023] Several improvement schemes have been proposed to optimize the cooling structure of the baffle column. Existing technology CN118423137A discloses a "combined cooling structure of baffle column and spanwise baffle ribs," in which the baffle ribs extend spanwise and are sinusoidal wave-shaped. By guiding the high-speed airflow between adjacent spanwise baffle columns to the leeward side of the baffle column, it improves the heat transfer capacity on the leeward side. However, in this structure, the wave-shaped ribs require the airflow to change direction multiple times during the flow guidance process, leading to increased local flow losses. Furthermore, the large contact angle between the ribs and the airflow easily induces boundary layer separation, limiting further improvement in heat transfer efficiency.

[0024] The prior art CN118423138A discloses a "combined cooling structure of turbulence column and flow direction turbulence ribs", in which the turbulence ribs extend in a corrugated shape along the flow direction, aiming to make the cooling airflow uniformly distributed along the spanwise direction and improve the heat transfer uniformity. However, the corrugated ribs of this structure mainly act on the spanwise distribution of airflow, and have a weak ability to directly scour the low-speed wake region on the leeward side of the turbulence column, making it difficult to effectively eliminate the problem of hot spot accumulation on the leeward side.

[0025] The prior art CN118532234A discloses a "figure-eight shaped oblique rib" cooling structure, which enhances local disturbance and cyclone by setting oblique ribs arranged in a figure-eight shape downstream of the turbulence column, thereby improving the heat transfer effect. However, the oblique ribs form a large angle with the airflow direction (usually 45° to 60°), and the airflow collides with the ribs at a large angle, resulting in a sudden change in the flow cross-sectional area, which significantly increases the flow resistance and limits the overall thermal performance.

[0026] Based on the above problems, this invention proposes a combined cooling structure of a baffle column and spanwise baffle rib for turbine blades to solve the problems existing in the prior art, improve the heat transfer level of the wall and the heat transfer capacity of the leeward side of the baffle column.

[0027] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0028] In one embodiment, refer to Figures 1-5 As shown, this embodiment provides a combined cooling structure of turbulence columns and flow direction turbulence ribs for turbine blades, which can be used for cooling turbine blades of aero engines and gas turbines, including an upper wall surface 2, a lower wall surface 3, multiple turbulence columns 1 and two sets of turbulence rib units 4. Multiple baffle columns 1 are arranged in an array and installed between the upper wall surface 2 and the lower wall surface 3. The upper end of the baffle column 1 is fixed to the lower end surface of the upper wall surface 2, and the lower end of the baffle column 1 is fixed to the upper end surface of the lower wall surface 3. An airflow channel is formed between the upper wall surface 2 and the lower wall surface 3. The cold air inlet of the airflow channel is in the direction of the outlet, which is the direction of fluid flow. Two sets of turbulence rib units 4 are symmetrically arranged and fixed to the lower end face of the upper wall 2 and the upper end face of the lower wall 3, respectively, thereby achieving turbulence on the upper wall 2 and the lower wall 3. The turbulence rib units in the same group are arranged in an array, and the turbulence column and the turbulence rib unit located downstream of it constitute a turbulence group. Each turbulence group is arranged at intervals along a direction perpendicular to the flow direction; along the flow direction, they are arranged in a cross pattern. The turbulence rib unit is located on the leeward side of its upstream turbulence column 1, and is funnel-shaped with its opening facing the fluid. Its opening guides the fluid, thereby guiding the airflow flowing through the turbulence column 1 to its leeward side, improving the problem of weak heat exchange capacity on the leeward side of the turbulence column 1, and improving the heat exchange uniformity of the upper wall 2 and the lower wall 3. The gaps in the turbulence rib units 4 do not affect the airflow direction to the windward side of the turbulence column 1.

[0029] Specifically, the direction of fluid flow is called the flow direction, and the direction perpendicular to the flow direction is called the spanwise direction. The turbulence column 1 has multiple rows in both the flow direction and the spanwise direction. The two rows of turbulence column 1 adjacent to each other in the flow direction are staggered, and the two rows of turbulence column 1 adjacent to each other in the spanwise direction are also staggered, which can further improve the turbulence effect and facilitate the arrangement of the turbulence rib unit 4.

[0030] Specifically, the diameter of the turbulence column 1 is D, and the height of the turbulence column 1 is H1, where H1 = 1.5D.

[0031] Specifically, the vertical distance between the axes of two adjacent turbulence columns 1 is S. x S x =5D; the distance between adjacent spoiler columns 1 arranged along the span is S. y S y =2.5D; the number of rows of the turbulence columns is 3 to 4 in the spanwise direction and 7 in the flowwise direction.

[0032] Specifically, the flow-guiding channel is formed by two ribs in the flow-guiding rib unit, the outlet width of the flow-guiding channel is B < D, and the flow-guiding channel is symmetrically arranged about the axis of its upstream flow-guiding column.

[0033] Specifically, the turbulence rib unit is a funnel-shaped structure composed of two symmetrically arranged concave arc ribs with a radius of R, where R = 0.8D to 1.2D; the center of a single rib of the turbulence rib unit is located on the perpendicular bisector of the line connecting the centers of two spanwise adjacent turbulence columns upstream of the turbulence rib unit, and the flow distance I between the center of a single rib and the connecting line satisfies: I = 0.6D to 1.5D.

[0034] Specifically, the height of the friction rib unit 4 is H2, where H2 = 0.25D to 0.5D; and the thickness of its ribs is W, where W = 0.05D to 0.3D.

[0035] In one embodiment, a design method for a combined cooling structure of a baffle column and a flow-direction baffle rib for turbine blades is disclosed, comprising the following steps: Step 1: Determine the parameters of the turbulence column array; Based on the cooling requirements of the turbine blade trailing edge, the diameter D of the turbulence column is determined to be 1 mm, and the flow direction spacing S is set. x =5D and spanning distance S y =2.5D, and the spoiler columns are arranged in a staggered manner to form a spoiler column array; Step 2: Determine the placement of the two sets of spoiler ribs; Two sets of ribs are symmetrically arranged on the upper and lower walls, respectively. An arc-shaped funnel-shaped rib unit is set on the leeward side of each turbulence column, so that the opening of the rib unit faces the direction of the airflow. Step 3: Construct the aerodynamic surface of the fringe rib unit; The inner wall profile of the turbulence rib is designed based on the cubic polynomial curve equation. A local coordinate system is established with the center of the outlet section of the turbulence rib unit as the origin and the counter-current direction as the positive X-axis. The parameters L and W in the curve equation are then determined. half_out W half_in And calculate coefficients A and B to make the curve satisfy the derivative y'(L) = 0 at the inlet, ensuring that the airflow enters in parallel without impact loss and the flow channel cross-sectional area transitions smoothly; Step 4: Determine the geometric parameters of the spoiler rib unit; The height of the rib unit is set to H2=0.25D, the rib thickness to W=0.05D, the radius to R=0.8D, and the flow distance between the center of the rib and the line connecting the upstream rib to the rib column to I=0.6D. Step 5: Form an alternating cooling structure; Two sets of turbulence ribs are arrayed on the upper and lower walls respectively. The turbulence column and the turbulence rib unit located downstream of it constitute a turbulence group. Each turbulence group is arranged at intervals in a direction perpendicular to the flow direction; and they are arranged in a cross pattern along the flow direction.

[0036] In one embodiment, a turbine blade includes a combined cooling structure of a turbulence column and a flow-direction turbulence rib designed using the above-described design method.

[0037] Application Examples: Example 1: The diameter of the baffle column 1 is D=1mm, the flow direction spacing of the baffle column 1 is Sx=2.5D, and the spacing between adjacent baffle columns 1 arranged along the spanwise direction is S y=2.5D, the height H1 of the spoiler column 1 is 1.5D, and the number of rows of spoiler columns 1 is N=7. The height H2 of the spoiler rib unit 4 is 0.25D, the rib thickness W of the spoiler rib unit 4 is 0.1D, and the vertical distance C1 between the axis of the spoiler rib unit 4 and the corresponding spoiler column 1 is 0.2076D~0.9D.

[0038] Example 2: Based on Example 1, the height of the turbulence rib unit 4 is changed from H2 in Example 1 to H3=0.5D.

[0039] Comparative example: Comparative Example 1: Based on the previous embodiment, the arc-shaped tapered spoiler ribs were replaced with figure-eight ribs. The diameter of the spoiler column is D=1mm, the flow spacing of the spoiler columns is Sx=2.5D, the spacing between adjacent spoiler columns arranged along the span is Sy=2.5D, the height of the spoiler column is H1=1.5D, and the number of rows of spoiler columns is N=7. The height of the spoiler rib unit is H4=0.25D, the rib thickness of the spoiler rib unit is W=0.1D, and the vertical distance between the axis of the spoiler rib unit and the corresponding spoiler column is C2=0.2076D~0.9D.

[0040] Comparative Example 2: Based on Example 1, the height of the spoiler rib was changed from H4 in Comparative Example 1 to H5 = 0.5D.

[0041] Reference Figure 6 As shown, the vortex cloud diagrams of Example 1 and Comparative Example 1 at Re=25000 are compared. It can be seen that Example 1 has wall-attached vortices behind the turbulence column, while Comparative Example 1 has obvious off-wall structures. The vortex structure near the wall in Example 1 makes its heat transfer performance behind the column higher than that in Comparative Example 1. At the same time, the wall-attached vortices in Example 1 are high-speed vortices compared to the off-wall vortices in Comparative Example 1. The high-speed wall-attached vortices enhance the heat transfer of the turbulence column, but at the same time, due to the streamlined structure of the example, the flow resistance of the fluid flow is reduced, so this example achieves a good balance between high heat transfer and low flow resistance.

[0042] Reference Figure 7 , Figure 8 As shown, the dimensionless cold air flow rate was compared. Re When the coefficient is 25000, the dimensionless heat transfer coefficient of the surface of the traditional cylindrical, unribbed, and unperforated turbulence column structure in Examples 1 and 2 is compared with that in Examples 1 and 2. NuThe comparison results are shown in the cloud map. It can be seen that the application of Example 1 makes the cold air more uniform in the airflow channel. From the heat transfer cloud map, the heat transfer is weakened near the two walls, while it is enhanced near the middle. Therefore, the heat transfer uniformity of the two walls is improved to a certain extent. In addition, the arrangement of the funnel-shaped ribs will further accelerate the high-speed airflow between the ribs and the adjacent turbulence column 1, which not only enhances the heat transfer capacity of the leeward area of ​​the turbulence column, but also enhances the heat transfer capacity of the windward side of the turbulence column 1.

[0043] Reference Figure 9 As shown, the dimensionless cold air flow rates were compared. Re When the temperature distribution of the first application example is 25000, the comparison results of the temperature distribution of the traditional turbulence column structure show that the overall temperature of the first application example is slightly higher than that of the traditional turbulence column structure, the low temperature area is significantly reduced, and the temperature distribution is more uniform.

[0044] Reference Figure 10 As shown, the dimensionless cold air flow rates were compared. Re When the coefficient is 25000, the spanwise average dimensionless heat transfer coefficient of Examples 1 and 2 and the traditional turbulence column structure are compared. Nu L The comparison results show that, compared with the traditional turbulence column structure, the application examples 1 and 2 have a higher average dimensionless heat transfer coefficient in the spanwise direction. Nu L Compared to traditional baffle columns, the funnel-shaped baffle ribs in the application examples improve heat transfer behind the baffle column, thereby improving the heat transfer uniformity of the wall surface and enhancing heat transfer.

[0045] Reference Figure 11 As shown, the dimensionless cold air flow rates were compared. Re When the coefficient is 25000, the average dimensionless heat transfer coefficient of the flow direction in Examples 1 and 2 and the traditional turbulence column structure are compared. Nu L The comparison results show that, compared with the traditional turbulence column structure, the first and second application examples have a higher average dimensionless heat transfer coefficient in the flow direction. Nu L Compared to traditional baffles, the funnel-shaped baffles in this application example enhance the airflow velocity behind the baffle column, resulting in a faster scouring speed of the cold airflow and thus improving convective heat transfer.

[0046] Reference Figure 12 As shown, the dimensionless cold air flow rates were compared. ReWhen the value is 25000, the comparison results of the ratio of the overall flow resistance of the channel to the flow resistance of the smooth pipe in Application Examples 1 and 2 and Comparative Examples 1 and 2 show that Application Examples 1 and 2 have lower flow resistance compared with Comparative Examples 1 and 2, which is about 5.86%-32.85% lower, and the higher the rib height, the more obvious the effect.

[0047] Reference Figure 13 As shown, the dimensionless cold air flow rates were compared. Re When the heat exchange rate is 25000, the comparison results of the overall heat exchange capacity of the channels in Application Examples 1 and 2 and Comparative Examples 1 and 2 show that Application Examples 1 and 2 have a stronger heat exchange capacity than Comparative Examples 1 and 2, which is about 3.24%-6.65% higher, and the higher the fin height, the more obvious the effect.

[0048] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention without departing from the principles and spirit of the present invention.

Claims

1. A combined cooling structure of a baffle column and a flow-direction baffle rib for turbine blades, characterized in that, It includes an upper and lower wall surface constituting a cooling airflow channel, and multiple turbulence columns and two sets of turbulence ribs disposed within the channel; each set of turbulence ribs includes several turbulence rib units; characterized in that: The multiple turbulence columns are arranged in an array and fixedly connected between the upper and lower walls to turbulent airflow and enhance wall heat exchange. The two sets of turbulence ribs are symmetrically arranged on the upper and lower walls, respectively. The turbulence column and the turbulence rib unit located downstream of it constitute a turbulence group. Each turbulence group is arranged at intervals along the direction perpendicular to the flow direction; and they are arranged in a cross pattern along the flow direction. The rib unit is constructed as an arc-shaped tapering guide structure with an opening facing the direction of airflow. Each rib unit is respectively set on the leeward side of each rib, forming a guide channel for collecting, accelerating and reorienting the high-speed main flow that bypasses the rib. The high-speed main flow that bypasses the upstream rib is smoothly guided to the leeward side region of the downstream adjacent rib, so as to compress and accelerate the low-speed wake region airflow on the leeward side.

2. The combined cooling structure of a baffle column and a flow-direction baffle rib for turbine blades according to claim 1, characterized in that: The inner wall of the turbulence rib unit is an aerodynamically optimized smooth curved surface, and its contour line satisfies a cubic polynomial curve equation. A local coordinate system is established with the center of the outlet section of the turbulence rib unit as the origin and the counter-current direction as the positive X-axis. The curve equation y(x) of the inner wall surface satisfies: Where y(x) is the vertical distance from the inner wall surface of the rib unit to its central axis; L is the flow length of the rib unit; W half_out W is half the width at the outlet of the spoiler rib unit. half_in This is half the width at the inlet of the friction rib unit; A and B are shape coefficients, determined by the boundary conditions: The equation of the curve satisfies the derivative y'(L) = 0 at the entrance.

3. The combined cooling structure of a baffle column and a flow-direction baffle rib for turbine blades according to claim 1, characterized in that: The turbulence rib unit includes two symmetrically arranged concave arc ribs in the shape of a funnel, wherein the larger diameter end of the funnel is the inlet of the turbulence rib unit and the smaller diameter end is the outlet of the turbulence rib unit; the radius R of the concave arc and the diameter D of the turbulence column satisfy: R = 0.8D ~ 1.2D.

4. The combined cooling structure of a baffle column and a flow-direction baffle rib for turbine blades according to claim 3, characterized in that: The center of a single rib of the turbulence rib unit is located on the perpendicular bisector of the line connecting the centers of two spanwise adjacent turbulence columns upstream of the turbulence rib unit, and the flow distance I between the center of a single rib and the connecting line satisfies: I = 0.6D ~ 1.5D.

5. The combined cooling structure of a baffle column and a flow-direction baffle rib for turbine blades according to claim 1, characterized in that: The height of the turbulence column H1 is 1D to 3D; The flow direction spacing S between the axes of two adjacent turbulence columns x =5D; The spanwise spacing S between two adjacent spoiler columns arranged along the spanwise direction y =2.5D; The number of rows of the turbulence-disrupting columns is 3 to 11 in the spanwise direction and 3 to 11 in the flowwise direction.

6. The combined cooling structure of a baffle column and a flow-direction baffle rib for turbine blades according to claim 1, characterized in that: The height H2 of the turbulence rib unit is 0.25D to 0.5D, and the rib thickness W is 0.05D to 0.3D.

7. The combined cooling structure of a baffle column and a flow-direction baffle rib for turbine blades according to claim 1, characterized in that: The flow-guiding channel is formed by two ribs in the flow-guiding rib unit. The outlet width of the flow-guiding channel is B < D, and the flow-guiding channel is symmetrical about the axis of its upstream flow-guiding column.

8. A design method for a combined cooling structure of a baffle column and a flow-direction baffle rib for turbine blades as described in any one of claims 1-7, characterized in that, Includes the following steps: Step 1: Determine the parameters of the turbulence column array; Based on the cooling requirements of the turbine blade trailing edge, determine the diameter D of the turbulence column and set the flow direction spacing S. x =5D and spanning distance S y =2.5D, and the spoiler columns are arranged in a staggered manner to form a spoiler column array; Step 2: Determine the placement of the two sets of spoiler ribs; Two sets of ribs are symmetrically arranged on the upper and lower walls, respectively. An arc-shaped funnel-shaped rib unit is set on the leeward side of each turbulence column, so that the opening of the rib unit faces the direction of the airflow. Step 3: Construct the aerodynamic surface of the fringe rib unit; The inner wall profile of the turbulence rib is designed based on the cubic polynomial curve equation. A local coordinate system is established with the center of the outlet section of the turbulence rib unit as the origin and the counter-current direction as the positive X-axis. The parameters L and W in the curve equation are then determined. half_out W half_in And calculate coefficients A and B to make the curve satisfy the derivative y'(L) = 0 at the inlet, ensuring that the airflow enters in parallel without impact loss and the flow channel cross-sectional area transitions smoothly; Step 4: Determine the geometric parameters of the spoiler rib unit; The height H2 of the friction rib unit is set to 0.25D~0.5D, the rib thickness W=0.05D~0.3D, the radius R=0.8D~1.2D, and the flow distance I between the center of the friction rib and the line connecting the upstream friction column is set to 0.6D~1.5D. Step 5: Form a cross-shaped cooling structure; Two sets of turbulence ribs are arrayed on the upper and lower walls respectively. The turbulence column and the turbulence rib unit located downstream of it constitute a turbulence group. Each turbulence group is arranged at intervals in a direction perpendicular to the flow direction; and they are arranged in a cross pattern along the flow direction.

9. A turbine blade, characterized in that: This includes a combined cooling structure of turbulence columns and flow-direction turbulence ribs designed using the design method described in claim 8.

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