Rapid design method for air film hole of air-cooled blade

Abstract

The invention discloses an air-cooled blade air film hole rapid design method, which comprises the following steps of: 1, creating a turbine blade model, and creating a plurality of air film holes in the turbine blade model; 2, extracting positioning information and shaping information of each air film hole, and converting the air film holes into imprinting surfaces based on the information; step 3, performing grouping naming operation on the impressing surface; step 4, performing grid size function setting on the impressing surface through auxiliary software so as to quickly adjust the distribution of the air film holes; and step 5, generating grids, adopting a mode of replacing solid film holes with the imprinting surfaces, and not creating detailed solid geometric features for each film hole, so that the number of required small-scale grids is effectively reduced, the demand on computing resources is reduced, and the quality of grid division and the efficiency of simulation calculation are improved.

Description

Technical Field

[0001] The invention relates to the technical field of aeroengine turbine blade design, and in particular to a method for quickly designing air film holes in air-cooled blades. Background Art

[0002] The working environment of turbine blades is extremely harsh, and their internal and external flow fields have strong three-dimensional characteristics, which requires comprehensive and accurate flow field and temperature field analysis of the internal and external channels of the blade cascade. The existence of complex internal serpentine cooling channels, air film holes, column ribs, trailing edge slits and other cooling structures greatly increases the workload and difficulty of analysis. The design of these cooling structures not only needs to consider the cooling efficiency, but also the mechanical strength and processing feasibility of the blades, making the design process more complicated.

[0003] As a key component of the cooling solution, the design of the air film hole usually requires multiple rounds of comparison and iteration of multiple solutions. Each iteration involves detailed flow field and temperature field analysis, and the length of these analysis cycles depends on the modeling speed of the geometric model, the efficiency of the meshing tool, and the experience and skill level of the researchers. In traditional methods, due to the lack of effective auxiliary tools and fast iteration mechanisms, the entire design cycle is long, making it difficult to quickly respond to market changes and technological advances.

[0004] The traditional design method of film holes for turbine blades uses a solid geometric model for subsequent meshing and simulation calculations. Although this method is intuitive, it requires a large number of small-scale meshes at the film hole locations to accurately describe the geometric details, which inevitably increases the number of meshes. Too many small-scale meshes not only increase the complexity of the simulation calculation, but also greatly increase the demand for computing resources, affecting the efficiency of the overall simulation calculation. In addition, the solid modeling method is not conducive to the rapid adjustment of the film hole layout, which limits the flexibility of the design scheme.

[0005] Therefore, it is necessary to provide a rapid design method for air film holes of air-cooled blades to solve the problems mentioned in the above background technology. Summary of the invention

[0006] To achieve the above object, the present invention provides the following technical solution: a method for quickly designing air film holes of an air-cooled blade, comprising: step 1: creating a turbine blade model, wherein a plurality of air film holes are created on the turbine blade model;

[0007] Step 2: extracting the positioning information and shaping information of each of the air film holes, and converting the air film holes into an imprinting surface based on the information;

[0008] Step 3: performing grouping and naming operations on the stamped surfaces;

[0009] Step 4: Setting a grid size function on the stamping surface through auxiliary software to quickly adjust the distribution of air film holes;

[0010] Step 5: Generate the grid.

[0011] Preferably, the stamping surface is a geometric plane or a curved surface.

[0012] Preferably, in step 3, the grouping and naming method of the stamping surface includes:

[0013] Based on the positioning information and shaping information of the air film holes on the stamping surface, a unique identifier is assigned to the inlet and outlet of each air film hole, and the holes are grouped and named according to a set naming rule to facilitate identification of the relationship between different air film holes.

[0014] Preferably, group naming is performed according to the naming rule of inlet / outlet+custom prefix+number.

[0015] Preferably, the custom prefix includes: increasing radius, decreasing radius, increasing axial direction or decreasing axial direction.

[0016] Preferably, in step five, the auxiliary software is Fluent Meshing software.

[0017] Preferably, in step five, the setting of the grid size function includes: selection and adjustment of a global size function, a local control function and a boundary layer control function, so as to control the scale of the grid.

[0018] Preferably, in step 2, the positioning information includes the positioning point coordinates and axis angle of the air film hole;

[0019] The shaping information includes the hole shape and hole shape geometric parameters of the air film hole.

[0020] Compared with the prior art, the present invention provides a method for quickly designing air film holes for air-cooled blades, which has the following beneficial effects:

[0021] 1. In the present invention, the imprinted surface is used instead of the physical air film hole. The inlet and outlet of the air film hole are marked by the imprinted surface, which greatly improves the speed of establishing the inlet and outlet of the air film hole. When performing simulation calculations, it is no longer necessary to create detailed physical geometric features for each air film hole, which effectively reduces the number of small-scale grids required, reduces the demand for computing resources, and improves the quality of grid division and the efficiency of simulation calculations. In addition, this method also allows the true shape of the inlet and outlet of the air film hole to be retained, making the results of the simulation calculation closer to the actual situation, further enhancing the accuracy and reliability of the simulation.

[0022] 2. In the present invention, in order to ensure the clear distinction between each air film hole and the accuracy of data processing, a systematic grouping mechanism is adopted. The inlet and outlet of each air film hole are assigned a unique identifier and named according to predefined rules. This not only helps to identify the relationship between different air film holes, but also facilitates subsequent data management and analysis, thereby improving the organization and orderliness of the design process. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is a flow chart of a rapid design method for air film holes in air-cooled blades. DETAILED DESCRIPTION

[0024] See also Figure 1 The present invention provides a method for quickly designing air film holes of an air-cooled blade, comprising:

[0025] Step 1: creating a turbine blade model, wherein a plurality of air film holes are created on the turbine blade model;

[0026] Step 2: extracting the positioning information and shaping information of each of the air film holes, and converting the air film holes into an imprinting surface based on the information;

[0027] Step 3: performing grouping and naming operations on the stamped surfaces;

[0028] Step 4: Setting a grid size function on the stamping surface through auxiliary software to quickly adjust the distribution of air film holes;

[0029] Specifically, the auxiliary software is Fluent Meshing software.

[0030] Step 5: Generate the grid.

[0031] It should be explained that in the traditional method, in order to accurately simulate the air film hole, a large number of small-scale grids are required to describe its geometric features, which not only increases the complexity of the calculation, but also increases the demand for computing resources. After the imprinted surface is used to replace the solid geometric model, the number of grids is greatly reduced, especially avoiding the generation of too many small-scale grids at the location of the air film hole. This change not only simplifies the meshing process, but also significantly reduces the resource consumption and time cost of simulation calculations.

[0032] Fewer grids mean lower computational complexity and faster computational speed, thus improving the efficiency of the overall simulation calculation. In addition, since the number of grids is reduced, subsequent data processing becomes simpler and more reliable, further enhancing the accuracy and reliability of the simulation.

[0033] Specifically, the stamping surface is a special geometric representation method and a non-physical structure.

[0034] The specific transformation method of the stamped surface is: use the positioning information and shaping information of the air film hole to mark the air inlet and outlet of the air film hole on the surface of the turbine blade, parameterize the air film hole features, and retain the true shape of the air film hole inlet and outlet through parameterization, avoid the creation of the solid geometric features of the air film hole, and improve the establishment speed of the air film hole inlet and outlet.

[0035] Furthermore, the stamping surface is a geometric plane or a curved surface.

[0036] Through the design method of the stamped surface, the real shape of the air film hole inlet and outlet is retained. When the simulated flow calculation is performed, the result is closer to the actual situation. Compared with the traditional method, this method can not only improve the accuracy of the flow calculation, but also better reflect the cooling performance under actual working conditions, providing a more reliable basis for the optimization design.

[0037] Furthermore, in order to ensure the distinction between the air film holes and the accuracy of data processing, in step three, the grouping and naming method of the stamping surface includes:

[0038] Based on the positioning information and shaping information of the air film holes on the stamping surface, the inlet and outlet of each air film hole are respectively assigned unique identifiers, such as inlet_01 and outlet_01, and are grouped and named according to the set naming rules to facilitate identification of the relationship between different air film holes, and at the same time, facilitate subsequent data management and analysis.

[0039] Furthermore, group and name them according to the naming rule of inlet / outlet+custom prefix+number.

[0040] Furthermore, in step three, the custom prefix includes: increasing radius, decreasing radius, increasing axial direction or decreasing axial direction, which makes the name of the stamping surface more intuitive and more practical, which not only enhances the flexibility of naming, but also facilitates user understanding and operation, and improves user experience.

[0041] Furthermore, in step five, the setting of the grid size function includes: selection and adjustment of a global size function, a local control function, and a boundary layer control function, which are used to control the scale of the grid (the density and distribution of the grid).

[0042] Among them, the global size function is usually used to define the mesh size of the entire model or most areas. It is suitable for situations where the geometry is relatively simple and there is no need to encrypt the mesh in a specific area. When the simulation does not require high mesh accuracy or the overall structure of the geometric model is uniform, select this function to adjust the mesh density. Specifically, in Fluent Meshing, you can adjust it by setting the maximum mesh size and the minimum mesh size value.

[0043] Local control functions are usually used to mesh specific areas in a geometric model, such as areas with complex geometry, large gradient changes, or areas that need to capture details. When the simulation needs to capture the flow details of these areas with high precision, select this function to adjust the mesh density. Specifically, in Fluent Meshing, you can adjust it by adding local size controls (such as curvature and proximity, etc.).

[0044] The boundary layer control function is usually used to generate high-quality boundary layer meshes near solid walls. When the simulation needs to capture the flow characteristics near the wall with high precision, select this function to adjust the mesh density. Specifically, in FluentMeshing, this can be achieved by adding boundary layer parameters. Users can select the area where the boundary layer needs to be generated and set parameters such as the number of boundary layer layers, the height of the first layer of mesh, and the growth rate. In addition, you can also select the distribution method of the boundary layer mesh, such as aspect ratio, uniform distribution, etc., to control the shape and density of the boundary layer mesh.

[0045] It needs to be explained that during the iteration process of the air film hole scheme, the data of the internal and external flow fields can be reused, thereby significantly shortening the calculation time required for each iteration, thereby avoiding the traditional method where each time the air film hole layout is modified, the entire grid needs to be regenerated and a new simulation calculation needs to be performed. The present invention only needs to update part of the grid to complete the new simulation task, greatly speeding up the design optimization.

[0046] At the same time, combined with efficient mesh generation tools such as Fluent Meshing, the present invention can generate high-quality meshes in a short time to meet the requirements of simulation calculations. Users can set global size functions, local control functions and boundary layer control functions according to their needs, flexibly control the density and distribution of the mesh, and maximize the calculation efficiency while ensuring the simulation accuracy. In addition, the mesh contains the identification and grouping information about the inlet and outlet stamping surfaces of the air film holes, which is convenient for subsequent fluid dynamics simulation calculations. Wherein, the Fluent Meshing software is prior art.

[0047] Furthermore, in step 2, the positioning information includes the positioning point coordinates and axis angle of the air film hole;

[0048] The shaping information includes the hole shape and hole shape geometric parameters of the air film hole.

[0049] Specifically, the hole types include cylindrical holes, conical holes, racetrack holes, dustpan holes, etc.

[0050] In another embodiment, if the turbine blade model described in step one requires newly designed air film holes, a corresponding stamping surface can be directly generated on the surface of the turbine blade model according to design parameters such as the positioning information and shaping information of each required air film hole to quickly establish the inlet and outlet of the air film hole.

[0051] In the specific implementation, a turbine blade model is created, on which a number of air film holes are created; the positioning information and shaping information of each of the air film holes are extracted, and based on the information, the air film holes are converted into imprinting surfaces; the imprinting surfaces are grouped and named; the mesh size function of the imprinting surface is set through Fluent Meshing software to achieve rapid adjustment of the distribution of the air film holes; and a mesh is generated.

[0052] What has been described above are only preferred specific implementations of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field, within the technical scope disclosed by the present invention, can make equivalent replacements or changes based on the technical solutions and inventive concepts of the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A rapid design method for air film holes of air-cooled blades, characterized in that: include: Step 1: creating a turbine blade model, wherein a plurality of air film holes are created on the turbine blade model; Step 2: extracting the positioning information and shaping information of each of the air film holes, and converting the air film holes into an imprinting surface based on the information; Step 3: performing grouping and naming operations on the stamped surfaces; Step 4: Setting a grid size function on the stamping surface through auxiliary software to quickly adjust the distribution of air film holes; Step 5: Generate the grid.

2. The rapid design method of air film holes for air-cooled blades according to claim 1 is characterized in that: The stamping surface is a geometric plane or a curved surface.

3. The rapid design method of air film holes for air-cooled blades according to claim 1 is characterized in that: In step 3, the grouping and naming method of the stamping surface includes: Based on the positioning information and shaping information of the air film holes on the stamping surface, a unique identifier is assigned to the inlet and outlet of each air film hole, and the holes are grouped and named according to a set naming rule to facilitate identification of the relationship between different air film holes.

4. The rapid design method of air film holes for air-cooled blades according to claim 3 is characterized in that: Group and name them according to the naming rule of inlet / outlet+custom prefix+number.

5. The rapid design method of air film holes for air-cooled blades according to claim 4 is characterized in that: The custom prefix includes: radius increasing, radius decreasing, axial increasing or axial decreasing.

6. The rapid design method of air film holes for air-cooled blades according to claim 1 is characterized in that: In step 4, the auxiliary software is Fluent Meshing software.

7. The rapid design method of air film holes for air-cooled blades according to claim 1 is characterized in that: In step five, the setting of the grid size function includes: selection and adjustment of a global size function, a local control function and a boundary layer control function, which are used to control the scale of the grid.

8. The rapid design method of air film holes for air-cooled blades according to claim 1 is characterized in that: In step 2, the positioning information includes the positioning point coordinates and axis angle of the air film hole; The shaping information includes the hole shape and hole shape geometric parameters of the air film hole.

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