Bitstream-based active cooling structure design method for additive manufacturing of flow-around runner

Abstract

The application discloses a kind of based on the active cooling structure design method of flow channel of flow around based on bit stream, comprising: obtaining the circumscribed circle corresponding to the avoidance area;According to the radius of circumscribed circle, obtain dipole strength term, different position plane streamline control point coordinates are obtained according to dipole strength term and preset different velocity potential;According to control point generation spline curve to fit plane streamline;The control point of plane streamline is mapped to the control point on the curved surface, and the curved surface streamline is established;The included angle between curved surface streamline and additive manufacturing direction is checked, if the included angle is greater than preset angle, then it does not meet the requirement, adjust the control point of curved surface streamline, obtain adjusted curved surface streamline;According to the cross-sectional shape of preset curved surface flow channel, using the scanning function of three-dimensional modeling software, curved surface flow channel is generated in active cooling structure according to adjusted curved surface streamline, and active cooling structure model is obtained.The application solves the problem of structure design under complex curved surface containing flow around flow channel.

Description

Technical Field

[0001] This invention belongs to the field of aircraft technology, and in particular relates to a design method for an additive manufacturing active cooling structure based on potential flow around a flow channel. Background Technology

[0002] During flight, aircraft generate significant heat through intense friction with the air, exceeding the melting point of alloys. Without heat-resistant materials, active structural cooling is necessary. This is achieved by delivering coolant through internal microchannels within the structure. However, designing these microchannels is extremely complex for mechanisms with complex shapes and internal interface requirements. Existing technologies also present challenges in designing structures with flow channels around complex curved surfaces. Summary of the Invention

[0003] The technical problem solved by this invention is to overcome the shortcomings of the prior art and provide a design method for an additive manufacturing active cooling structure based on potential flow channels, which solves the structural design problem of complex curved surfaces containing flow channels.

[0004] The objective of this invention is achieved through the following technical solution: a design method for an additive manufacturing active cooling structure based on potential flow around a flow channel, comprising: Step S1: obtaining the circumcircle corresponding to the avoidance area required by the active cooling structure; obtaining the dipole strength term in the cylindrical disturbance equation according to the radius of the circumcircle; obtaining the coordinates of control points of planar streamlines at different positions according to the dipole strength term and different velocity potentials in the preset cylindrical flow equation; and generating spline curves based on the control points to fit the planar streamlines; Step S2: mapping the control points of the planar streamlines onto a curved surface. Step S3: Obtain control points on the curved surface and establish surface streamlines based on the control points on the curved surface; Step S4: Check the angle α between the surface streamlines and the additive manufacturing direction. If the angle α is greater than the preset angle, the requirement is not met. Adjust the control points of the surface streamlines to ensure that the angle between the surface streamlines and the additive manufacturing direction is greater than the preset angle, and obtain the adjusted surface streamlines; Step S5: According to the adjusted surface streamlines and the preset cross-sectional shape of the surface flow channel, use the sweep function of the 3D modeling software to generate the surface flow channel in the active cooling structure, and obtain the active cooling structure model.

[0005] The above-mentioned design method for active cooling structure in additive manufacturing of flow channels based on potential flow further includes: Step S5: Import the active cooling structure model into finite element analysis software, define the material properties of the active cooling structure, mesh the structure, define the working temperature and pressure of the flow channel, and submit the calculation to obtain the stress; Step S6: Determine whether the stress is lower than the design value. If the stress is lower than the design value, the design requirements are met; Step S7: If the stress is not lower than the design value, the design requirements are not met. Adjust the cross-sectional shape of the curved flow channel and repeat steps S4 to S6 until the design requirements are met.

[0006] In the above-mentioned active cooling structure design method for additive manufacturing of flow channels based on potential flow, the avoidance area includes openings, sensor pin holes, and stiffener connections.

[0007] In the above design method for active cooling structure of additive manufacturing around a flow channel based on potential flow, the coordinates of the control points of the planar streamline are obtained by the following formula: ; in, This refers to the dipole strength term in the cylindrical perturbation equation. For different velocity potentials in the flow equation around a cylinder The x-coordinate of the control point of the streamline in the plane. The vertical coordinates of the control points for the plane streamlines are given.

[0008] In the above-mentioned active cooling structure design method for additive manufacturing based on potential flow channels, the preset angle is 60°.

[0009] In the above-mentioned active cooling structure design method for additive manufacturing based on potential flow channels, in step S3, if the requirements are not met, the additive manufacturing direction is adjusted to ensure that the angle between the curved streamline and the additive manufacturing direction is greater than a preset angle.

[0010] In the above-mentioned active cooling structure design method for additive manufacturing of flow channels based on potential flow, the streamline of the curved surface is the axis of the curved flow channel.

[0011] A design system for an additive manufacturing active cooling structure based on potential flow around a flow channel includes: a first module for obtaining the circumcircle corresponding to the avoidance area required by the active cooling structure; obtaining the dipole strength term in the cylindrical disturbance equation according to the radius of the circumcircle; obtaining the control point coordinates of the planar streamline at different positions based on the dipole strength term and different velocity potentials in the preset cylindrical flow equation; and generating spline curves to fit the planar streamlines based on the control points; and a second module for mapping the control points of the planar streamlines onto a curved surface to obtain the control points on the curved surface. The first module establishes the surface streamline based on the control points on the surface; the second module checks the angle α between the surface streamline and the additive manufacturing direction. If the angle α is greater than the preset angle, the requirement is not met, and the control points of the surface streamline are adjusted to ensure that the angle between the surface streamline and the additive manufacturing direction is greater than the preset angle, thus obtaining the adjusted surface streamline; the third module generates the surface flow channel in the active cooling structure according to the adjusted surface streamline and the preset cross-sectional shape of the surface flow channel using the sweep function of the 3D modeling software, thus obtaining the active cooling structure model.

[0012] The above-mentioned active cooling structure design system for additive manufacturing of flow channels based on potential flow also includes: a fifth module, used to import the active cooling structure model into finite element analysis software, define the material properties of the active cooling structure, generate a mesh, define the working temperature and pressure of the flow channel, and submit the calculation to obtain the stress; and a sixth module, used to determine whether the stress is lower than the design value. If the stress is lower than the design value, then the design requirements are met.

[0013] An electronic device includes: a memory for storing computer-readable instructions; and a processor for executing the computer-readable instructions to perform a bit-flow-based additive manufacturing active cooling structure design method.

[0014] Compared with the prior art, the present invention has the following advantages: This invention solves the structural design problem of flow channels on complex curved surfaces, greatly improving the design efficiency of flow channels on complex curved surfaces and enhancing the design quality of active cooling structures. Attached Figure Description

[0015] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings: Figure 1 This is a flowchart of the active cooling structure design method for additive manufacturing of flow channels based on potential flow provided in this embodiment of the invention; Figure 2 This is a schematic diagram of the generation of streamlines provided in an embodiment of the present invention; Figure 3 This is a schematic diagram of streamlined surface mapping provided in an embodiment of the present invention; Figure 4 This is a schematic diagram of additive manufacturing angle inspection provided in an embodiment of the present invention; Figure 5 This is a schematic diagram of the flow channel structure generation provided in an embodiment of the present invention; Figure 6 This is a schematic diagram of the strength verification of the flow channel structure provided in an embodiment of the present invention. Detailed Implementation

[0016] Exemplary embodiments of the present disclosure will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided to enable a more thorough understanding of the present disclosure and to fully convey the scope of the disclosure to those skilled in the art. It should be noted that, unless otherwise specified, the embodiments and features described herein can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0017] Figure 1 This is a flowchart of the active cooling structure design method for additive manufacturing of flow channels based on potential flow, provided in an embodiment of the present invention. Figure 1 As shown, the method includes the following steps: Step S1: Based on the avoidance area required by the active cooling structure, obtain the circumcircle corresponding to the avoidance area; obtain the dipole strength term in the cylindrical turbulence equation according to the radius of the circumcircle; obtain the control point coordinates of the planar streamline at different positions according to the dipole strength term and the different velocity potentials in the preset cylindrical flow equation; generate spline curves based on the control points to fit the planar streamline. Step S2: Map the control points of the planar streamline onto the curved surface to obtain the control points on the curved surface, and establish the surface streamline based on the control points on the curved surface; Step S3: Check the angle α between the surface streamline and the additive manufacturing direction. If the angle α is greater than the preset angle, the requirement is not met. Adjust the control points of the surface streamline to ensure that the angle between the surface streamline and the additive manufacturing direction is greater than the preset angle, and obtain the adjusted surface streamline. Step S4: Based on the adjusted surface streamlines (the surface streamlines are the axes of the surface flow channels) and the preset cross-sectional shape of the surface flow channels, use the sweep function of the 3D modeling software to generate the surface flow channels in the active cooling structure to obtain the active cooling structure model.

[0018] The method also includes the following steps: Step S5: Import the active cooling structure model into the finite element analysis software, define the material properties of the active cooling structure, mesh the structure, define the working temperature and pressure of the flow channel, and submit the calculation to obtain the stress. Step S6: Determine if the stress is lower than the design value. If the stress is lower than the design value, the design requirements are met. Step S7: If the stress is not lower than the design value, the design requirements are not met. Adjust the cross-sectional shape of the curved flow channel and repeat steps S4 to S6 until the design requirements are met.

[0019] It should be understood that steps S5 to S7 are optional.

[0020] The avoidance area includes openings, sensor pin holes, and reinforcing rib connections.

[0021] The coordinates of the control points of the streamline in the plane are obtained by the following formula: ; in, This refers to the dipole strength term in the cylindrical perturbation equation. For different velocity potentials in the flow equation around a cylinder The x-coordinate of the control point of the streamline in the plane. The vertical coordinates of the control points for the plane streamlines are given.

[0022] The preset angle is 60°.

[0023] In step S3, if the requirements are not met, the additive manufacturing direction is adjusted to ensure that the angle between the surface streamline and the additive manufacturing direction is greater than a preset angle.

[0024] Specifically, the method includes the following steps ( Figure 1 ): Step 1: Based on the required clearance area of ​​the active cooling structure (such as openings, sensor pin holes, and stiffener connections), obtain the circumcircle corresponding to the clearance area. Using the radius of the circumcircle, derive the dipole strength term in the cylindrical turbulence equation. Different velocity potentials in the pre-defined flow equations around a cylinder The coordinates of the control points of the planar streamlines at different positions are obtained based on the dipole strength term and different velocity potentials in the flow equation around the cylinder: ; in, For velocity potential, adjust Streamlines at different locations can be obtained. Describing the strength of a dipole for cylindrical turbulence, Let be the radius of the cylinder. and The coordinates of the control points describing the streamlines. Given the velocity potential. Solving the above equation yields a streamline at a specific location. Adjustment It can adjust the overall curvature of the curve. The larger the radius, the greater the streamline curvature. It should be set according to the radius of the circumcircle of the area to be avoided. This ensures that the flow can pass through the channel.

[0025] The plane streamline is fitted by generating spline curves based on control points. Figure 2 ).

[0026] Step 2: Based on the mapping relationship between the plane and the curved surface, and according to the arc length of each section of the curved surface, map the control points of the plane streamline onto the curved surface proportionally to obtain the control points on the curved surface. Then, establish the surface streamline based on the control points on the curved surface. Figure 3 ).

[0027] Step 3: Check the angle α between the streamlined surface in Step 2 and the additive manufacturing direction. If the angle α is greater than 60°, it does not meet the requirements. Adjust the control points of the streamlined surface to meet the process requirements; or adjust the additive manufacturing direction. Figure 4 To meet process requirements, the adjusted curved streamline is obtained.

[0028] Step 4: Based on the streamlined surface adjusted in Step 3 (the streamlined surface is the axis of the flow channel), and according to the preset cross-sectional shape of the flow channel, use the sweep function of the 3D modeling software to generate the flow channel in the active cooling structure. Figure 5 ), thus obtaining the active cooling structure model.

[0029] Step 5: Based on the product formed in Step 4, and the operating temperature, pressure, and load of the structure, perform finite element analysis (FEM) verification of the flow channel structure. The FEM verification first involves importing the active cooling structure model from Step 4 into the FEM software, defining the material properties of the active cooling structure, meshing, defining the operating temperature and pressure of the flow channel, and submitting the calculation. Check if the stress in the calculation results is lower than the design value. If it is lower, the design requirements are met, and the structure is usable. If the design requirements are not met, adjust the cross-sectional shape from Step 4, and repeat Steps 4 and 5 until the design requirements are met. Figure 6 The result is an active cooling structure with a flow channel that can be manufactured using additive manufacturing. This structure consists of only one part, which contains a flow channel inside.

[0030] This embodiment describes the design of an active cooling channel, including steps such as streamline generation, streamline surface mapping, additive manufacturing angle checking, channel structure generation, and channel structure strength verification. The final structural design was verified through experiments. The flowchart is shown below. Figure 1 The specific details are as follows: (1) Generation of streamlines around the flow The streamlined ribs are synthesized by the function of the straight DC and the dipole, and the result is a cylindrical turbulence, as shown in the following equation: ; in, For velocity potential, adjust Streamlines at different locations can be obtained. Describing the strength of a dipole for cylindrical turbulence, Let be the radius of the cylinder. and The coordinates of the control points describing the streamlines. Given the velocity potential. Solving the above equation yields a streamline at a specific location. Adjustment It can adjust the overall curvature of the curve. The larger the radius, the greater the streamline curvature. It should be set according to the radius of the circumcircle of the area to be avoided. This ensures that the flow can pass through the channel.

[0031] In practice, multiple control points are set on the streamline in the plane, and spline curves are generated based on the control points to approximate the streamline. Figure 2 ).

[0032] (2) Streamline surface mapping The streamlines in (1) above are generated based on planar flow. For the flow channels in the curved skin, the planar flow streamlines need to be mapped onto the curved surface. Based on the arc length of each section of the curved surface, the control points of the planar flow streamlines are mapped onto the curved surface proportionally, and then streamlines are established on the curved surface based on the control points. Figure 3 ).

[0033] (3) Angle inspection in additive manufacturing Based on the product's orientation during additive manufacturing, check the angle between the streamlines and the deposition direction. This angle must not exceed the equipment's forming limit. If it exceeds the limit, adjust the streamlines locally or adjust the product's orientation. Figure 4 ).

[0034] (4) Generation of flow channel structure Select a suitable flow channel cross section, and generate the flow channel structure by sweeping according to the generated streamlines. Figure 5 ).

[0035] (5) Strength check of flow channel structure Finite element analysis was performed on the flow channel structure based on the operating temperature, pressure, and load, and optimization was carried out based on the analysis results.

[0036] This embodiment also provides a design system for an additive manufacturing active cooling structure based on potential flow in a flow channel. The system includes: a first module, used to obtain the circumcircle corresponding to the avoidance area required by the active cooling structure; obtain the dipole strength term in the cylindrical turbulence equation according to the radius of the circumcircle; obtain the control point coordinates of the planar streamlines at different positions based on the dipole strength term and different velocity potentials in the preset cylindrical flow equation; and generate spline curves based on the control points to fit the planar streamlines; a second module, used to map the control points of the planar streamlines onto a curved surface to obtain... The first module uses control points on the curved surface to establish the surface streamline. The second module checks the angle α between the surface streamline and the additive manufacturing direction. If the angle α is greater than the preset angle, the requirement is not met. The control points of the surface streamline are adjusted to ensure that the angle between the surface streamline and the additive manufacturing direction is greater than the preset angle, resulting in the adjusted surface streamline. The third module uses the sweep function of 3D modeling software to generate the surface flow channel in the active cooling structure according to the adjusted surface streamline and the preset cross-sectional shape of the surface flow channel, thus obtaining the active cooling structure model.

[0037] The system also includes: a fifth module, used to import the active cooling structure model into the finite element analysis software, define the material properties of the active cooling structure, generate a mesh, define the working temperature and pressure of the flow channel, and submit the calculation to obtain the stress; and a sixth module, used to determine whether the stress is lower than the design value. If the stress is lower than the design value, then the design requirements are met.

[0038] This embodiment also provides an electronic device, including: a memory for storing computer-readable instructions; and a processor for running the computer-readable instructions to execute a bit-flow-based additive manufacturing active cooling structure design method.

[0039] This embodiment makes it possible for the internal flow channel to avoid local structures through the potential flow equation. This embodiment also significantly improves the design efficiency of flow channels around complex curved surfaces and enhances the design quality of active cooling structures through programming. Furthermore, this embodiment automatically completes additive manufacturing process checks to ensure the feasibility of the design scheme.

[0040] Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make possible changes and modifications to the technical solutions of the present invention by utilizing the methods and techniques disclosed above without departing from the spirit and scope of the present invention. Therefore, any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solutions of the present invention shall fall within the protection scope of the technical solutions of the present invention.

Claims

1. A design method for an additive manufacturing active cooling structure based on potential flow in a flow channel, characterized in that... include: Step S1: Based on the avoidance area required by the active cooling structure, obtain the circumcircle corresponding to the avoidance area; The dipole strength term in the cylindrical flow equation is obtained according to the radius of the circumcircle. The coordinates of the control points of the planar streamlines at different positions are obtained according to the dipole strength term and the different velocity potentials in the preset cylindrical flow equation. Spline curves are generated based on the control points to fit the planar streamlines. Step S2: Map the control points of the planar streamline onto the curved surface to obtain the control points on the curved surface, and establish the surface streamline based on the control points on the curved surface; Step S3: Check the angle α between the surface streamline and the additive manufacturing direction. If the angle α is greater than the preset angle, the requirement is not met. Adjust the control points of the surface streamline to ensure that the angle between the surface streamline and the additive manufacturing direction is greater than the preset angle, and obtain the adjusted surface streamline. Step S4: Based on the adjusted surface streamlines and the preset cross-sectional shape of the surface flow channel, use the sweep function of the 3D modeling software to generate the surface flow channel in the active cooling structure to obtain the active cooling structure model.

2. The active cooling structure design method for additive manufacturing based on potential flow channels according to claim 1, characterized in that... Also includes: Step S5: Import the active cooling structure model into the finite element analysis software, define the material properties of the active cooling structure, mesh the structure, define the working temperature and pressure of the flow channel, and submit the calculation to obtain the stress. Step S6: Determine if the stress is lower than the design value. If the stress is lower than the design value, the design requirements are met. Step S7: If the stress is not lower than the design value, the design requirements are not met. Adjust the cross-sectional shape of the curved flow channel and repeat steps S4 to S6 until the design requirements are met.

3. The active cooling structure design method for additive manufacturing based on potential flow channels according to claim 1, characterized in that: The avoidance area includes openings, sensor pin holes, and reinforcing rib connections.

4. The active cooling structure design method for additive manufacturing based on potential flow channels according to claim 1, characterized in that: The coordinates of the control points of the streamline in the plane are obtained by the following formula: ； in, This refers to the dipole strength term in the cylindrical perturbation equation. For different velocity potentials in the flow equation around a cylinder The x-coordinate of the control point of the streamline in the plane. The vertical coordinates of the control points for the plane streamlines are given.

5. The active cooling structure design method for additive manufacturing based on potential flow channels according to claim 1, characterized in that: The preset angle is 60°.

6. The active cooling structure design method for additive manufacturing based on potential flow channels according to claim 1, characterized in that: In step S3, if the requirements are not met, the additive manufacturing direction is adjusted to ensure that the angle between the surface streamline and the additive manufacturing direction is greater than a preset angle.

7. The active cooling structure design method for additive manufacturing based on potential flow channels according to claim 1, characterized in that: The streamlines of the curved surface are the axes of the curved flow channel.

8. A design system for an active cooling structure in additive manufacturing based on potential flow channels, characterized in that... include: The first module is used to obtain the circumcircle corresponding to the avoidance area required by the active cooling structure; obtain the dipole strength term in the cylindrical turbulence equation according to the radius of the circumcircle; obtain the control point coordinates of the planar streamline at different positions according to the dipole strength term and the different velocity potentials in the preset cylindrical flow equation; and generate spline curves based on the control points to fit the planar streamline. The second module is used to map the control points of the planar streamlines onto the curved surface to obtain the control points on the curved surface, and to establish the surface streamlines based on the control points on the curved surface. The third module is used to check the angle α between the surface streamline and the additive manufacturing direction. If the angle α is greater than the preset angle, the requirement is not met. The control points of the surface streamline are adjusted to ensure that the angle between the surface streamline and the additive manufacturing direction is greater than the preset angle, and the adjusted surface streamline is obtained. The fourth module is used to generate the surface flow channel in the active cooling structure according to the adjusted surface streamline and the preset cross-sectional shape of the surface flow channel, using the sweep function of the 3D modeling software, and obtain the active cooling structure model.

9. The active cooling structure design system for additive manufacturing based on potential flow channels according to claim 8, characterized in that... Also includes: The fifth module is used to import the active cooling structure model into the finite element analysis software, define the material properties of the active cooling structure, generate a mesh, define the working temperature and pressure of the flow channel, and submit the calculation to obtain the stress. The sixth module is used to determine whether the stress is lower than the design value. If the stress is lower than the design value, the design requirements are met.

10. An electronic device, characterized in that, include: Memory: Used to store computer-readable instructions; as well as Processor: for executing the computer-readable instructions to perform the method as described in any one of claims 1 to 7.

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