Finite element mesh adjustment methods, systems, equipment and media
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2022-08-29
- Publication Date
- 2026-08-14
AI Technical Summary
[0004]本公开要解决的技术问题是为了克服现有技术中调整圆孔位置后需要重新划分有限元网格并计算应力的缺陷，提供一种有限元网格调整方法、系统、设备和介质
[0050] The positive and progressive effects of this disclosure are as follows: Based on the changes of the circular hole before and after the adjustment position, the node adjustment area of the finite element mesh that needs to be adjusted synchronously is determined, and the adjustment direction and adjustment distance of the target node in the area are determined. The adjustment is based on the original mesh model without changing the overall mesh configuration and layout of the original structure. The node movement is based on the mesh size itself, which can better ensure the mesh quality. The adjusted finite element mesh meets the conditions for further design analysis, avoids re-meshing, reduces workload, saves finite element modeling time, avoids reapplying loads and boundary conditions, and improves design analysis efficiency.
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Figure CN117669280B_ABST
Abstract
Description
Technical Field
[0001] This disclosure relates to the field of engineering design technology, and in particular to a finite element mesh adjustment method, system, device and medium. Background Technology
[0002] Circular holes are common structural features in engineering, such as those found in blades, disks, and casings of aero-engines. These holes serve functions including ventilation, fluid flow, cooling, weight reduction, and condition monitoring. However, the presence of circular holes can lead to stress concentration and excessive stress in localized areas near them. Currently, engineering practices generally use the finite element method (FEM) to analyze the stress intensity of engineering structures (including structures with holes), and circular holes are a key area of focus in FEM stress analysis. The typical FEM process involves importing the geometric model of the structure with holes (created in geometric modeling software) into FEM meshing software or performing mesh generation within the FEM software itself, then adding boundary constraints and loads, and finally performing stress analysis.
[0003] In structural design, analysis, and optimization, adjustments to circular holes may be necessary. A common practice is to adjust the holes in geometric modeling software, then import the adjusted structural geometric model into finite element meshing or analysis software to re-mesh and perform calculations. This method is suitable for situations with a limited number of adjustments, as meshing can sometimes be very time-consuming. Furthermore, after re-meshing, the information of the original nodes changes, and the displacements and loads applied to the original nodes need to be reapplied. Summary of the Invention
[0004] The technical problem to be solved by this disclosure is to overcome the shortcomings of the prior art that requires re-dividing the finite element mesh and calculating the stress after adjusting the position of the circular hole, and to provide a finite element mesh adjustment method, system, device and medium.
[0005] This disclosure solves the above-mentioned technical problems through the following technical solution:
[0006] This disclosure provides a finite element mesh adjustment method, including:
[0007] Obtain the position information of the first circular hole and node positions on the finite element mesh before adjusting the position of the circular hole;
[0008] Obtain the position information of the second circular hole after adjusting its position;
[0009] The node adjustment area, the adjustment direction, and the adjustment distance of the target node in the node adjustment area are determined based on the first circular hole position information, the second circular hole position information, and the node position information; wherein, the first circular hole position information includes the position information of the center of the first circular hole, and the adjustment distance is negatively correlated with the radial distance, and the radial distance is the distance between the target node and the center of the first circular hole on the diameter of the circular hole.
[0010] Preferably, determining the node adjustment area and the adjustment direction and adjustment distance of the target node in the node adjustment area based on the first circular hole position information, the second circular hole position information, and the node position information includes:
[0011] The node adjustment area, the adjustment direction, and the moving distance of the center of the circular hole are determined based on the position information of the first and second circular holes.
[0012] The adjustment distance is determined based on the position information of the center of the first circular hole, the node adjustment area, the position information of the target node, and the moving distance.
[0013] Preferably, the first circular hole position information also includes the radius of the circular hole, and the second circular hole position information includes information about the center of the second circular hole;
[0014] The step of determining the node adjustment area, the adjustment direction, and the moving distance of the center of the circular hole based on the position information of the first and second circular holes includes:
[0015] The moving direction and moving distance of the center of the circular hole are determined based on the position information of the center of the first circular hole and the position information of the center of the second circular hole, and the adjustment direction is the same as the moving direction;
[0016] The maximum radius of the node adjustment area relative to the center of the first circular hole is determined based on the radius and the moving distance. The node adjustment area is the area outside the circular hole and whose distance from the center of the first circular hole is within the maximum radius.
[0017] The step of determining the adjustment distance based on the position information of the center of the first circular hole, the node adjustment area, the position information of the target node, and the moving distance includes:
[0018] The radial distance is calculated based on the position information of the center of the first circular hole and the position information of the target node;
[0019] The adjustment distance is calculated based on the radial distance, the radius, the maximum radius, and the moving distance, wherein the adjustment distance is linearly positively correlated with the moving distance.
[0020] Preferably, when the radial distance is equal to the radius, the adjustment distance is equal to the moving distance;
[0021] When the radial distance is equal to the maximum radius, the adjustment distance is equal to zero.
[0022] Preferably, the adjustment distance is expressed by the following formula:
[0023]
[0024] Wherein, ΔX represents the adjustment distance, ΔP represents the movement distance, R represents the radius, R1 represents the maximum radius, and X1 represents the radial distance.
[0025] Preferably, the maximum radius is greater than or equal to twice the radius.
[0026] Preferably, when the moving distance is less than the radius, the maximum radius is equal to twice the radius.
[0027] This disclosure also provides a finite element mesh adjustment system, including: a first acquisition module, a second acquisition module, and a calculation module;
[0028] The first acquisition module is used to acquire the position information of the first circular hole and the node position information on the finite element mesh before adjusting the position of the circular hole;
[0029] The second acquisition module is used to acquire the position information of the second circular hole after adjusting its position;
[0030] The calculation module is used to determine the node adjustment area and the adjustment direction and adjustment distance of the target node in the node adjustment area based on the first circular hole position information, the second circular hole position information and the node position information; wherein, the first circular hole position information includes the position information of the center of the first circular hole, and the adjustment distance is negatively correlated with the radial distance, and the radial distance is the distance between the target node and the center of the first circular hole on the diameter of the circular hole.
[0031] Preferably, the computing module includes: a first computing unit and a second computing unit;
[0032] The first calculation unit is used to determine the node adjustment area, the adjustment direction, and the moving distance of the center of the circular hole based on the first circular hole position information and the second circular hole position information;
[0033] The second calculation unit is used to determine the adjustment distance based on the position information of the center of the first circular hole, the node adjustment area, the position information of the target node, and the moving distance.
[0034] Preferably, the first circular hole position information also includes the radius of the circular hole, and the second circular hole position information includes information about the center of the second circular hole;
[0035] The first calculation unit includes: a directional distance calculation subunit and a maximum radius calculation subunit;
[0036] The direction and distance calculation subunit is used to determine the moving direction and the moving distance of the center of the circular hole based on the position information of the center of the first circular hole and the position information of the center of the second circular hole, wherein the adjustment direction is the same as the moving direction;
[0037] The maximum radius calculation subunit is used to determine the maximum radius of the node adjustment area relative to the center of the first circular hole based on the radius and the moving distance. The node adjustment area is the area outside the circular hole and whose distance from the center of the first circular hole is within the maximum radius.
[0038] The second calculation unit includes: a radial distance calculation subunit and an adjustment distance calculation subunit;
[0039] The radial distance calculation subunit is used to calculate the radial distance based on the position information of the center of the first circular hole and the position information of the target node;
[0040] The adjustment distance calculation subunit is used to calculate the adjustment distance based on the radial distance, the radius, the maximum radius, and the movement distance, wherein the adjustment distance is linearly positively correlated with the movement distance.
[0041] Preferably, when the radial distance is equal to the radius, the adjustment distance is equal to the moving distance;
[0042] When the radial distance is equal to the maximum radius, the adjustment distance is equal to zero.
[0043] Preferably, the adjustment distance is expressed by the following formula:
[0044]
[0045] Wherein, ΔX represents the adjustment distance, ΔP represents the movement distance, R represents the radius, R1 represents the maximum radius, and X1 represents the radial distance.
[0046] Preferably, the maximum radius is greater than or equal to twice the radius.
[0047] Preferably, when the moving distance is less than the radius, the maximum radius is equal to twice the radius.
[0048] This disclosure also provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the aforementioned finite element mesh adjustment method.
[0049] This disclosure also provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the aforementioned finite element mesh adjustment method.
[0050] The positive and progressive effects of this disclosure are as follows: Based on the changes of the circular hole before and after the adjustment position, the node adjustment area of the finite element mesh that needs to be adjusted synchronously is determined, and the adjustment direction and adjustment distance of the target node in the area are determined. The adjustment is based on the original mesh model without changing the overall mesh configuration and layout of the original structure. The node movement is based on the mesh size itself, which can better ensure the mesh quality. The adjusted finite element mesh meets the conditions for further design analysis, avoids re-meshing, reduces workload, saves finite element modeling time, avoids reapplying loads and boundary conditions, and improves design analysis efficiency. Attached Figure Description
[0051] Figure 1 This is a flowchart of the finite element mesh adjustment method of Embodiment 1 of this disclosure.
[0052] Figure 2 This is a schematic diagram showing the movement of the center of the circular hole on section M in the finite element mesh adjustment method of Embodiment 1 of this disclosure.
[0053] Figure 3 This is an example of a rectangular coordinate system in the finite element mesh adjustment method of Embodiment 1 of this disclosure.
[0054] Figure 4 This is a schematic diagram of the node adjustment region and target node B on section M in the finite element mesh adjustment method of Embodiment 1 of this disclosure.
[0055] Figure 5 This is a flowchart of a specific implementation of step S13 in the finite element mesh adjustment method of Embodiment 1 of this disclosure.
[0056] Figure 6 This is a flowchart of another specific implementation of step S13 in the finite element mesh adjustment method of Embodiment 1 of this disclosure.
[0057] Figure 7 The original mesh model diagram is an example of the finite element mesh adjustment method in Embodiment 1 of this disclosure.
[0058] Figure 8 This is a mesh model diagram of an adjustment result from an example of the finite element mesh adjustment method in Embodiment 1 of this disclosure.
[0059] Figure 9 This is a mesh model diagram of another adjustment result in the finite element mesh adjustment method of Embodiment 1 of this disclosure.
[0060] Figure 10 This is a mesh model diagram of another adjustment result in the finite element mesh adjustment method of Embodiment 1 of this disclosure.
[0061] Figure 11 This is a mesh model diagram of another adjustment result in the finite element mesh adjustment method of Embodiment 1 of this disclosure.
[0062] Figure 12 This is a mesh model diagram of another adjustment result in the finite element mesh adjustment method of Embodiment 1 of this disclosure.
[0063] Figure 13 This is a schematic diagram of the module of the finite element mesh adjustment system of Embodiment 2 of this disclosure.
[0064] Figure 14 This is a schematic diagram of the structure of the electronic device according to Embodiment 3 of this disclosure. Detailed Implementation
[0065] The present disclosure is further illustrated below by way of embodiments, but the present disclosure is not limited to the scope of the embodiments described herein.
[0066] Example 1
[0067] This embodiment provides a finite element mesh adjustment method, referring to... Figure 1 Finite element mesh adjustment methods include:
[0068] S11. Obtain the position information of the first circular hole and the node position information on the finite element mesh before adjusting the position of the circular hole.
[0069] S12. Obtain the position information of the second circular hole after adjusting the position of the circular hole.
[0070] S13. Determine the node adjustment area and the adjustment direction and adjustment distance of the target node within the node adjustment area based on the first circular hole position information, the second circular hole position information, and the node position information. The first circular hole position information includes the position information of the center of the first circular hole. The adjustment distance is negatively correlated with the radial distance, which is the distance between the target node and the center of the first circular hole along the diameter of the hole.
[0071] Adjusting the position of the circular hole involves moving it parallel to the axis while keeping its axial direction unchanged. The shape and size of the circular hole remain unchanged before and after adjustment, and it does not intersect with other structural features on the finite element mesh, thus not affecting other structural features.
[0072] Since the axial direction of the circular hole remains unchanged before and after adjustment, and the axis before adjustment is parallel to the axis after adjustment, and the circular hole moves parallel to the axis in a direction perpendicular to the axis, the direction and distance of movement of the circular hole's center can be reflected by the direction and distance of movement of the hole's center on any cross-section perpendicular to the axis. The axis of the circular hole includes the set of the circular hole's centers on all cross-sections.
[0073] For ease of calculation, the adjustment direction and adjustment distance of the target node can be calculated by using a cross-section that includes the target node and is perpendicular to the axis.
[0074] Specifically, assume that the cross section including the target node B and perpendicular to the axis is M. Figure 2 The diagram illustrates the movement of the center of a circular hole on section M. The solid line represents the circular hole before adjustment, point O represents the center of the circular hole before adjustment (i.e., the center of the first circular hole), the dashed line represents the circular hole after adjustment, and point O′ represents the center of the circular hole after adjustment. OO′ represents the displacement of the center of the circular hole, and the line segment from point O to point O′ points in the direction of movement of the center of the circular hole. The length of the line segment OO′ is the distance the center of the circular hole moves.
[0075] The direction and distance of movement of the center of the circular hole can be represented in several ways, one of which is through a coordinate system established with point O as the origin. Figure 3 An example of a rectangular coordinate system is shown. Figure 2 and Figure 3 In this diagram, point O is the origin, the Z-axis represents the axial direction of the circular hole, and the Z-axis direction is along the axial direction. The X and Y axes are on section M, with the X-axis pointing towards the reference direction (OX) for adjusting the position of the circular hole, and the Y-axis perpendicular to the X and Z axes and determined by the right-hand rule. θ is the angle between OX and OO′, which can be used to represent the direction of movement of the center of the circular hole.
[0076] Since finite element meshing software and finite element software can usually automatically convert the coordinates of the original coordinate system to the coordinates of the new coordinate system after constructing the new coordinate system, this function can be used to quickly obtain the required data by constructing a new coordinate system.
[0077] For example, with Figure 2Establish a cylindrical coordinate system with the center O of the circular hole as the origin. The Z-axis represents the axial direction of the cylindrical coordinate system / circular hole, and its direction is along the axial direction. The X-axis represents the radial direction of the cylindrical coordinate system / circular hole, and the Y-axis represents the circumferential direction of the cylindrical coordinate system / circular hole. The angle θ can be quickly obtained from the circumferential coordinates of point O′ in the cylindrical coordinate system, and the movement distance ΔP of the center of the circular hole can be quickly obtained from the radial coordinates of point O′ in the cylindrical coordinate system.
[0078] For example, to Figure 3 In the rectangular coordinate system, the X-axis and Y-axis are rotated around the origin O by an angle θ to obtain the X′-axis and Y′-axis, so that the X′-axis overlaps with OO′. Then, the value of the X′-axis coordinate of point O′ in the new coordinate system of X′-axis, Y′-axis and Z-axis is equal to the length of OO′. In other words, the moving distance ΔP of the center of the circular hole can be quickly obtained by the coordinate of point O′ on the X′-axis.
[0079] Figure 4 A schematic diagram of the node adjustment region and target node B on section M is shown. The dashed line represents the outer edge of the node adjustment region, and the solid circle represents the edge of the circular hole before its position is adjusted. Point A is the intersection of line OB and the edge of the circular hole, and point C is the intersection of the extension of line OB and the outer edge. Target node B is located between points A and C. The inner and outer edges of the node adjustment region are determined by the position information of the circular hole before and after adjustment and the node position information on the finite element mesh. The solid circle is also the inner edge of the node adjustment region, and the node adjustment region cannot intersect with other structural features on the finite element mesh. Under the condition that the node adjustment region does not intersect with other structural features on the finite element mesh, the larger the movement distance OO′ of the circular hole center, the larger the outer edge of the node adjustment region can be set.
[0080] The adjustment direction of target node B is determined by the movement direction of the center of the circular hole. For example, the adjustment direction of target node B is the same as the movement direction of the center of the circular hole, that is, target node B moves parallel to the center of the circular hole.
[0081] The length of line OB is the radial distance between target node B and the center O of the first circular hole. If a target node exists at point C, the radial distance OC is greater than the radial distance OB, and the adjustment distance of target node C is less than the adjustment distance of target node B. If a target node exists at point A, the radial distance OA is less than the radial distance OB, and the adjustment distance of target node A is greater than the adjustment distance of target node B.
[0082] The adjusted position information of target node B can be obtained by updating the adjustment direction and adjustment distance of target node B.
[0083] In this embodiment, based on the changes in the circular hole before and after the adjustment position, the node adjustment area of the finite element mesh that needs to be adjusted synchronously is determined, and the adjustment direction and adjustment distance of the target node in the area are determined. The adjustment is carried out based on the original mesh model without changing the overall mesh configuration and layout of the original structure. The node movement is based on the mesh size itself, which can better ensure the mesh quality. The adjusted finite element mesh meets the conditions for further design analysis, avoids re-meshing, reduces workload, saves finite element modeling time, avoids reapplying loads and boundary conditions, and improves design analysis efficiency.
[0084] In specific implementation, refer to Figure 5 Step S13 includes:
[0085] S131. Determine the node adjustment area, adjustment direction, and moving distance of the center of the hole based on the position information of the first and second holes.
[0086] S132. Determine the adjustment distance based on the position information of the center of the first circular hole, the node adjustment area, the position information of the target node, and the moving distance.
[0087] The position information of the first and second circular holes can determine the node adjustment area, adjustment direction, and the moving distance of the center of the circular hole. For example, the node adjustment area, adjustment direction, and moving distance of the center of the circular hole can be determined by the movement of the center of the circular hole.
[0088] The node adjustment area can be established around the center of the first circular hole. The greater the radial distance between the target node and the center of the first circular hole, the smaller the adjustment distance of the target node; the smaller the radial distance between the target node and the center of the first circular hole, the greater the adjustment distance of the target node.
[0089] In practice, the location information of the first circular hole also includes the radius of the circular hole, and the location information of the second circular hole includes the information of the center of the second circular hole.
[0090] Reference Figure 6 Step S131 includes:
[0091] S1311. Determine the moving direction and moving distance of the center of the circular hole based on the position information of the center of the first circular hole and the position information of the center of the second circular hole, and adjust the direction to be the same as the moving direction.
[0092] S1312. Determine the maximum radius of the node adjustment area relative to the center of the first circular hole based on the radius and the moving distance. The node adjustment area is the area outside the circular hole and within the maximum radius of the distance from the center of the first circular hole.
[0093] Step S132 includes:
[0094] S1321. The radial distance is calculated based on the position information of the center of the first circular hole and the position information of the target node.
[0095] S1322. The adjustment distance is calculated based on the radial distance, radius, maximum radius, and moving distance, wherein the adjustment distance is linearly positively correlated with the moving distance.
[0096] In this embodiment, based on the changes in the circular hole before and after the adjustment position, the node adjustment area of the finite element mesh that needs to be adjusted synchronously is determined, and the adjustment direction and adjustment distance of the target node in this area are determined. The adjustment direction is the same as the movement direction. The adjustment is based on the original mesh model and does not change the overall mesh configuration and layout of the original structure. The adjustment distance is linearly positively correlated with the movement distance. The node movement is based on the mesh size itself, which can better ensure the mesh quality. The adjusted finite element mesh meets the conditions for further design analysis, avoids re-meshing, reduces workload, saves finite element modeling time, avoids reapplying loads and boundary conditions, and improves design analysis efficiency.
[0097] In practice, when the radial distance is equal to the radius, the adjustment distance is equal to the movement distance.
[0098] When the radial distance equals the maximum radius, the adjustment distance is zero.
[0099] Among them, with Figure 4 For example, if a target node exists at point C, the adjustment distance of target node C is zero. If a target node exists at point A, the adjustment distance of target node A is equal to the movement distance ΔP of the center of the circular hole.
[0100] In practice, the following formula is used to represent the adjustment distance:
[0101]
[0102] Where ΔX represents the adjustment distance, ΔP represents the movement distance, R represents the radius, R1 represents the maximum radius, and X1 represents the radial distance.
[0103] by Figure 4 For example, to facilitate the calculation of the adjustment distance ΔX of target node B, assume that there are also target nodes at points A and C. Then, the adjustment distance of target node A is equal to the movement distance ΔP of the center of the circular hole, and the adjustment distance of target node C is zero. The adjustment directions of target nodes A, B, and C are the same as the movement direction of the center of the circular hole. In the figure, the solid arrow with point A as the endpoint represents the adjustment displacement of target node A, and the solid arrow with point B as the endpoint represents the adjustment displacement of target node B. The solid arrows point in the adjustment direction, and the length of the solid arrow represents the adjustment distance.
[0104] Based on the properties of similar triangles, we get:
[0105] ΔX / ΔP = BC / AC.
[0106] At the same time, BC = R1 - X1 and AC = R1 - R, we can obtain:
[0107]
[0108] X1 can be quickly obtained from the radial coordinates of the target node B in the cylindrical coordinate system with point O as the origin, as described above.
[0109] After calculating ΔX, the coordinates X2 of the target node B along the X′ axis can be obtained using the Cartesian coordinate system with point O as the origin, as described above. Then, the coordinates X3 of the target node B along the adjusted X′ axis can be calculated quickly.
[0110] X3 = X2 + ΔX.
[0111] In this embodiment, based on the changes in the circular hole's position before and after adjustment, the node adjustment region of the finite element mesh that needs to be adjusted synchronously is determined, and the adjustment direction and distance of the target nodes within this region are also determined. Adjustment is performed based on the original mesh model, without changing the overall mesh configuration and layout of the original structure. Node movement based on the mesh's own dimensions can better ensure mesh quality. The adjusted finite element mesh meets the conditions for further design analysis, avoiding the need for re-meshing, reducing workload, saving finite element modeling time, and avoiding the reapplication of loads and boundary conditions, thus improving design analysis efficiency. This finite element mesh adjustment method is adaptable to various meshes / elements, including hexahedral and tetrahedral meshes. Due to its high adjustment efficiency, it can be applied to various scenarios such as structural optimization design, sensitivity analysis, and reliability assessment.
[0112] In practice, the maximum radius is greater than or equal to twice the radius.
[0113] Preferably, for faster calculation, the maximum radius can be set to twice the radius. Alternatively, when the moving distance is greater than or equal to the radius, the maximum radius can be set to the sum of the moving distance and the radius.
[0114] In practice, when the moving distance is less than the radius, the maximum radius is equal to twice the radius.
[0115] Figure 7-12 An example of a finite element mesh adjustment method is shown. Wherein, Figure 7 The original mesh model before adjusting the position of the circular hole is shown; the radius of the hole is approximately 0.65 mm. For this original mesh model, Figure 8 The mesh model with node adjustment is shown, where θ is 45 degrees and ΔP is 0.3 mm. Figure 9The mesh model with node adjustment is shown, where θ is 90 degrees and ΔP is 0.3 mm. Figure 10 The mesh model with node adjustment is shown, where θ is 135 degrees and ΔP is 0.3 mm. Figure 11 The mesh model with node adjustment is shown with θ = 0 degrees and ΔP = 0.3 mm. Figure 12 The mesh model with node adjustment is shown, where θ is 240 degrees and ΔP is 0.3 mm.
[0116] Example 2
[0117] This embodiment provides a finite element mesh adjustment system, referring to... Figure 13 The finite element mesh adjustment system includes: a first acquisition module 21, a second acquisition module 22, and a calculation module 23.
[0118] The first acquisition module 21 is used to acquire the position information of the first circular hole and the node position information on the finite element mesh before adjusting the position of the circular hole.
[0119] The second acquisition module 22 is used to acquire the position information of the second circular hole after adjusting its position.
[0120] The calculation module 23 is used to determine the node adjustment area, the adjustment direction, and the adjustment distance of the target node within the node adjustment area based on the first circular hole position information, the second circular hole position information, and the node position information. The first circular hole position information includes the position information of the center of the first circular hole. The adjustment distance is negatively correlated with the radial distance, which is the distance between the target node and the center of the first circular hole along the diameter of the hole.
[0121] Adjusting the position of the circular hole involves moving it parallel to the axis while keeping its axial direction unchanged. The shape and size of the circular hole remain unchanged before and after adjustment, and it does not intersect with other structural features on the finite element mesh, thus not affecting other structural features.
[0122] Since the axial direction of the circular hole remains unchanged before and after adjustment, and the axis before adjustment is parallel to the axis after adjustment, and the circular hole moves parallel to the axis in a direction perpendicular to the axis, the direction and distance of movement of the circular hole's center can be reflected by the direction and distance of movement of the hole's center on any cross-section perpendicular to the axis. The axis of the circular hole includes the set of the circular hole's centers on all cross-sections.
[0123] For ease of calculation, the adjustment direction and adjustment distance of the target node can be calculated by using a cross-section that includes the target node and is perpendicular to the axis.
[0124] Specifically, assume that the cross section including the target node B and perpendicular to the axis is M. Figure 2The diagram illustrates the movement of the center of a circular hole on section M. The solid line represents the circular hole before adjustment, point O represents the center of the circular hole before adjustment (i.e., the center of the first circular hole), the dashed line represents the circular hole after adjustment, and point O′ represents the center of the circular hole after adjustment. OO′ represents the displacement of the center of the circular hole, and the line segment from point O to point O′ points in the direction of movement of the center of the circular hole. The length of the line segment OO′ is the distance the center of the circular hole moves.
[0125] The direction and distance of movement of the center of the circular hole can be represented in several ways, one of which is through a coordinate system established with point O as the origin. Figure 3 An example of a rectangular coordinate system is shown. Figure 2 and Figure 3 In this diagram, point O is the origin, the Z-axis represents the axial direction of the circular hole, and the Z-axis direction is along the axial direction. The X and Y axes are on section M, with the X-axis pointing towards the reference direction (OX) for adjusting the position of the circular hole, and the Y-axis perpendicular to the X and Z axes and determined by the right-hand rule. θ is the angle between OX and OO′, which can be used to represent the direction of movement of the center of the circular hole.
[0126] Since finite element meshing software and finite element software can usually automatically convert the coordinates of the original coordinate system to the coordinates of the new coordinate system after constructing the new coordinate system, this function can be used to quickly obtain the required data by constructing a new coordinate system.
[0127] For example, with Figure 2 Establish a cylindrical coordinate system with the center O of the circular hole as the origin. The Z-axis represents the axial direction of the cylindrical coordinate system / circular hole, and its direction is along the axial direction. The X-axis represents the radial direction of the cylindrical coordinate system / circular hole, and the Y-axis represents the circumferential direction of the cylindrical coordinate system / circular hole. The angle θ can be quickly obtained from the circumferential coordinates of point O′ in the cylindrical coordinate system, and the movement distance ΔP of the center of the circular hole can be quickly obtained from the radial coordinates of point O′ in the cylindrical coordinate system.
[0128] For example, to Figure 3 In the rectangular coordinate system, the X-axis and Y-axis are rotated around the origin O by an angle θ to obtain the X′-axis and Y′-axis, so that the X′-axis overlaps with OO′. Then, the value of the X′-axis coordinate of point O′ in the new coordinate system of X′-axis, Y′-axis and Z-axis is equal to the length of OO′. In other words, the moving distance ΔP of the center of the circular hole can be quickly obtained by the coordinate of point O′ on the X′-axis.
[0129] Figure 4A schematic diagram of the node adjustment region and target node B on section M is shown. The dashed line represents the outer edge of the node adjustment region, and the solid circle represents the edge of the circular hole before its position is adjusted. Point A is the intersection of line OB and the edge of the circular hole, and point C is the intersection of the extension of line OB and the outer edge. Target node B is located between points A and C. The inner and outer edges of the node adjustment region are determined by the position information of the circular hole before and after adjustment and the node position information on the finite element mesh. The solid circle is also the inner edge of the node adjustment region, and the node adjustment region cannot intersect with other structural features on the finite element mesh. Under the condition that the node adjustment region does not intersect with other structural features on the finite element mesh, the larger the movement distance OO′ of the circular hole center, the larger the outer edge of the node adjustment region can be set.
[0130] The adjustment direction of target node B is determined by the movement direction of the center of the circular hole. For example, the adjustment direction of target node B is the same as the movement direction of the center of the circular hole, that is, target node B moves parallel to the center of the circular hole.
[0131] The length of line OB is the radial distance between target node B and the center O of the first circular hole. If a target node exists at point C, the radial distance OC is greater than the radial distance OB, and the adjustment distance of target node C is less than the adjustment distance of target node B. If a target node exists at point A, the radial distance OA is less than the radial distance OB, and the adjustment distance of target node A is greater than the adjustment distance of target node B.
[0132] The adjusted position information of target node B can be obtained by updating the adjustment direction and adjustment distance of target node B.
[0133] In this embodiment, based on the changes in the circular hole before and after the adjustment position, the node adjustment area of the finite element mesh that needs to be adjusted synchronously is determined, and the adjustment direction and adjustment distance of the target node in the area are determined. The adjustment is carried out based on the original mesh model without changing the overall mesh configuration and layout of the original structure. The node movement is based on the mesh size itself, which can better ensure the mesh quality. The adjusted finite element mesh meets the conditions for further design analysis, avoids re-meshing, reduces workload, saves finite element modeling time, avoids reapplying loads and boundary conditions, and improves design analysis efficiency.
[0134] In a specific implementation, the calculation module 23 includes: a first calculation unit 231 and a second calculation unit 232.
[0135] The first calculation unit 231 is used to determine the node adjustment area, adjustment direction, and moving distance of the center of the hole based on the position information of the first and second holes.
[0136] The second calculation unit 232 is used to determine the adjustment distance based on the position information of the center of the first circular hole, the node adjustment area, the position information of the target node, and the moving distance.
[0137] The position information of the first and second circular holes can determine the node adjustment area, adjustment direction, and the moving distance of the center of the circular hole. For example, the node adjustment area, adjustment direction, and moving distance of the center of the circular hole can be determined by the movement of the center of the circular hole.
[0138] The node adjustment area can be established around the center of the first circular hole. The greater the radial distance between the target node and the center of the first circular hole, the smaller the adjustment distance of the target node; the smaller the radial distance between the target node and the center of the first circular hole, the greater the adjustment distance of the target node.
[0139] In practice, the location information of the first circular hole also includes the radius of the circular hole, and the location information of the second circular hole includes the information of the center of the second circular hole.
[0140] The first calculation unit 231 includes: a direction distance calculation subunit 2311 and a maximum radius calculation subunit 2312.
[0141] The direction and distance calculation subunit 2311 is used to determine the moving direction and moving distance of the center of the circular hole based on the position information of the center of the first circular hole and the position information of the center of the second circular hole, and adjust the direction to be the same as the moving direction.
[0142] The maximum radius calculation subunit 2312 is used to determine the maximum radius of the node adjustment area relative to the center of the first circular hole based on the radius and the moving distance. The node adjustment area is the area outside the circular hole and within the maximum radius of the distance from the center of the first circular hole.
[0143] The second calculation unit 232 includes: a radial distance calculation subunit 2321 and an adjustment distance calculation subunit 2322.
[0144] The radial distance calculation subunit 2321 is used to calculate the radial distance based on the position information of the center of the first circular hole and the position information of the target node.
[0145] The adjustment distance calculation subunit 2322 is used to calculate the adjustment distance based on the radial distance, radius, maximum radius and moving distance, wherein the adjustment distance is linearly positively correlated with the moving distance.
[0146] In this embodiment, based on the changes in the circular hole before and after the adjustment position, the node adjustment area of the finite element mesh that needs to be adjusted synchronously is determined, and the adjustment direction and adjustment distance of the target node in this area are determined. The adjustment direction is the same as the movement direction. The adjustment is based on the original mesh model and does not change the overall mesh configuration and layout of the original structure. The adjustment distance is linearly positively correlated with the movement distance. The node movement is based on the mesh size itself, which can better ensure the mesh quality. The adjusted finite element mesh meets the conditions for further design analysis, avoids re-meshing, reduces workload, saves finite element modeling time, avoids reapplying loads and boundary conditions, and improves design analysis efficiency.
[0147] In practice, when the radial distance is equal to the radius, the adjustment distance is equal to the movement distance.
[0148] When the radial distance equals the maximum radius, the adjustment distance is zero.
[0149] Among them, with Figure 4 For example, if a target node exists at point C, the adjustment distance of target node C is zero. If a target node exists at point A, the adjustment distance of target node A is equal to the movement distance ΔP of the center of the circular hole.
[0150] In practice, the following formula is used to represent the adjustment distance:
[0151]
[0152] Where ΔX represents the adjustment distance, ΔP represents the movement distance, R represents the radius, R1 represents the maximum radius, and X1 represents the radial distance.
[0153] by Figure 4 For example, to facilitate the calculation of the adjustment distance ΔX of target node B, assume that there are also target nodes at points A and C. Then, the adjustment distance of target node A is equal to the movement distance ΔP of the center of the circular hole, and the adjustment distance of target node C is zero. The adjustment directions of target nodes A, B, and C are the same as the movement direction of the center of the circular hole. In the figure, the solid arrow with point A as the endpoint represents the adjustment displacement of target node A, and the solid arrow with point B as the endpoint represents the adjustment displacement of target node B. The solid arrows point in the adjustment direction, and the length of the solid arrow represents the adjustment distance.
[0154] Based on the properties of similar triangles, we get:
[0155] ΔX / ΔP = BC / AC.
[0156] At the same time, BC = R1 - X1 and AC = R1 - R, we can obtain:
[0157]
[0158] X1 can be quickly obtained from the radial coordinates of the target node B in the cylindrical coordinate system with point O as the origin, as described above.
[0159] After calculating ΔX, the coordinates X2 of the target node B along the X′ axis can be obtained using the Cartesian coordinate system with point O as the origin, as described above. Then, the coordinates X3 of the target node B along the adjusted X′ axis can be calculated quickly.
[0160] X3 = X2 + ΔX.
[0161] In this embodiment, based on the changes in the circular hole's position before and after adjustment, the node adjustment region of the finite element mesh that needs to be adjusted synchronously is determined, and the adjustment direction and distance of the target nodes within this region are also determined. Adjustment is performed based on the original mesh model, without changing the overall mesh configuration and layout of the original structure. Node movement based on the mesh's own dimensions can better ensure mesh quality. The adjusted finite element mesh meets the conditions for further design analysis, avoiding the need for re-meshing, reducing workload, saving finite element modeling time, and avoiding the reapplication of loads and boundary conditions, thus improving design analysis efficiency. This finite element mesh adjustment method is adaptable to various meshes / elements, including hexahedral and tetrahedral meshes. Due to its high adjustment efficiency, it can be applied to various scenarios such as structural optimization design, sensitivity analysis, and reliability assessment.
[0162] In practice, the maximum radius is greater than or equal to twice the radius.
[0163] Preferably, for faster calculation, the maximum radius can be set to twice the radius. Alternatively, when the moving distance is greater than or equal to the radius, the maximum radius can be set to the sum of the moving distance and the radius.
[0164] In practice, when the moving distance is less than the radius, the maximum radius is equal to twice the radius.
[0165] Figure 7-12 An example of a finite element mesh adjustment method is shown. Wherein, Figure 7 The original mesh model before adjusting the position of the circular hole is shown; the radius of the hole is approximately 0.65 mm. For this original mesh model, Figure 8 The mesh model with node adjustment is shown, where θ is 45 degrees and ΔP is 0.3 mm. Figure 9 The mesh model with node adjustment is shown, where θ is 90 degrees and ΔP is 0.3 mm. Figure 10 The mesh model with node adjustment is shown, where θ is 135 degrees and ΔP is 0.3 mm. Figure 11 The mesh model with node adjustment is shown with θ = 0 degrees and ΔP = 0.3 mm. Figure 12 The mesh model with node adjustment is shown, where θ is 240 degrees and ΔP is 0.3 mm.
[0166] Example 3
[0167] Figure 14 This is a schematic diagram of the structure of an electronic device provided in Embodiment 3 of this disclosure. The electronic device includes a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the program, it implements the finite element mesh adjustment method in Embodiment 1. Figure 14 The electronic device 30 shown is merely an example and should not impose any limitation on the functionality and scope of use of the embodiments disclosed herein.
[0168] The electronic device 30 may be in the form of a general-purpose computing device, such as a server device. The components of the electronic device 30 may include, but are not limited to: at least one processor 31, at least one memory 32, and a bus 33 connecting different system components (including memory 32 and processor 31).
[0169] Bus 33 includes a data bus, an address bus, and a control bus.
[0170] The memory 32 may include volatile memory, such as random access memory (RAM) 321 and / or cache memory 322, and may further include read-only memory (ROM) 323.
[0171] The memory 32 may also include a program / utility 325 having a set (at least one) of program modules 324, including but not limited to: an operating system, one or more application programs, other program modules, and program data, each or some combination of these examples may include an implementation of a network environment.
[0172] The processor 31 executes various functional applications and data processing by running computer programs stored in the memory 32, such as the finite element mesh adjustment method in Embodiment 1 of this disclosure.
[0173] Electronic device 30 can also communicate with one or more external devices 34 (e.g., buttons, pointing devices, etc.). This communication can be performed via input / output (I / O) interface 35. Furthermore, the model-generated electronic device 30 can also communicate with one or more networks (e.g., local area network (LAN), wide area network (WAN), and / or public networks, such as the Internet) via network adapter 36. As shown in the figure, network adapter 36 communicates with other modules of the model-generated electronic device 30 via bus 33. It should be understood that, although not shown in the figure, other hardware and / or software modules can be used in conjunction with the model-generated electronic device 30, including but not limited to: microcode, device drivers, redundant processors, external disk drive arrays, RAID (disk array) systems, tape drives, and data backup storage systems.
[0174] It should be noted that although several modules / modules or sub-modules / modules of the electronic device have been mentioned in the detailed description above, this division is merely exemplary and not mandatory. In fact, according to embodiments of this disclosure, the features and functions of two or more modules / modules described above can be embodied in one module / module; conversely, the features and functions of one module / module described above can be further divided into multiple modules / modules.
[0175] Example 4
[0176] This embodiment provides a computer-readable storage medium on which a computer program is stored, which, when executed by a processor, implements the finite element mesh adjustment method in Embodiment 1.
[0177] The readable storage medium may be more specifically adopted, including but not limited to: portable disk, hard disk, random access memory, read-only memory, erasable programmable read-only memory, optical storage device, magnetic storage device, or any suitable combination thereof.
[0178] In a possible implementation, this disclosure can also be implemented as a program product comprising program code that, when the program product is run on a terminal device, causes the terminal device to execute the finite element mesh adjustment method of Embodiment 1.
[0179] The program code for executing this disclosure can be written in any combination of one or more programming languages, and the program code can be executed entirely on a user device, partially on a user device, as a stand-alone software package, partially on a user device and partially on a remote device, or entirely on a remote device.
[0180] While specific embodiments of this disclosure have been described above, those skilled in the art should understand that these are merely illustrative examples, and the scope of protection of this disclosure is defined by the appended claims. Those skilled in the art can make various changes or modifications to these embodiments without departing from the principles and essence of this disclosure, but all such changes and modifications fall within the scope of protection of this disclosure.
Claims
1. A finite element mesh adjustment method, characterized in that, include: Obtain the position information of the first circular hole and node positions on the finite element mesh before adjusting the position of the circular hole; Obtain the position information of the second circular hole after adjusting its position; The node adjustment area, the adjustment direction, and the adjustment distance of the target node in the node adjustment area are determined based on the first circular hole position information, the second circular hole position information, and the node position information; wherein, the first circular hole position information includes the position information of the center of the first circular hole, and the adjustment distance is negatively correlated with the radial distance, and the radial distance is the distance between the target node and the center of the first circular hole on the diameter of the circular hole.
2. The finite element mesh adjustment method as described in claim 1, characterized in that, The step of determining the node adjustment area and the adjustment direction and adjustment distance of the target node in the node adjustment area based on the first circular hole position information, the second circular hole position information, and the node position information includes: The node adjustment area, the adjustment direction, and the moving distance of the center of the circular hole are determined based on the position information of the first and second circular holes. The adjustment distance is determined based on the position information of the center of the first circular hole, the node adjustment area, the position information of the target node, and the moving distance.
3. The finite element mesh adjustment method as described in claim 2, characterized in that, The first circular hole position information also includes the radius of the circular hole, and the second circular hole position information includes information about the center of the second circular hole; The step of determining the node adjustment area, the adjustment direction, and the moving distance of the center of the circular hole based on the position information of the first and second circular holes includes: The moving direction and moving distance of the center of the circular hole are determined based on the position information of the center of the first circular hole and the position information of the center of the second circular hole, and the adjustment direction is the same as the moving direction. The maximum radius of the node adjustment area relative to the center of the first circular hole is determined based on the radius and the moving distance. The node adjustment area is the area outside the circular hole and whose distance from the center of the first circular hole is within the maximum radius. The step of determining the adjustment distance based on the position information of the center of the first circular hole, the node adjustment area, the position information of the target node, and the moving distance includes: The radial distance is calculated based on the position information of the center of the first circular hole and the position information of the target node; The adjustment distance is calculated based on the radial distance, the radius, the maximum radius, and the moving distance, wherein the adjustment distance is linearly positively correlated with the moving distance.
4. The finite element mesh adjustment method as described in claim 3, characterized in that, When the radial distance is equal to the radius, the adjustment distance is equal to the movement distance; When the radial distance is equal to the maximum radius, the adjustment distance is equal to zero.
5. The finite element mesh adjustment method as described in claim 3, characterized in that, The adjustment distance is expressed by the following formula: Wherein, ΔX represents the adjustment distance, ΔP represents the movement distance, R represents the radius, R1 represents the maximum radius, and X1 represents the radial distance.
6. The finite element mesh adjustment method as described in claim 3, characterized in that, The maximum radius is greater than or equal to twice the radius.
7. The finite element mesh adjustment method as described in claim 6, characterized in that, When the moving distance is less than the radius, the maximum radius is equal to twice the radius.
8. A finite element mesh adjustment system, characterized in that, include: The module consists of a first acquisition module, a second acquisition module, and a calculation module. The first acquisition module is used to acquire the position information of the first circular hole and the node position information on the finite element mesh before adjusting the position of the circular hole; The second acquisition module is used to acquire the position information of the second circular hole after adjusting its position; The calculation module is used to determine the node adjustment area and the adjustment direction and adjustment distance of the target node in the node adjustment area based on the first circular hole position information, the second circular hole position information and the node position information; wherein, the first circular hole position information includes the position information of the center of the first circular hole, and the adjustment distance is negatively correlated with the radial distance, and the radial distance is the distance between the target node and the center of the first circular hole on the diameter of the circular hole.
9. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes a computer program, it implements the finite element mesh adjustment method as described in any one of claims 1 to 7.
10. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the finite element mesh adjustment method according to any one of claims 1 to 7.
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