Traction fan lightweight method and device, storage medium and product

Abstract

The invention discloses a traction fan lightening method and device, a storage medium and a product, and relates to the field of structure optimization. The method comprises the steps that topological optimization calculation is conducted on a base finite element model, the base finite element model is lightened according to an optimization result, and a base model after primary optimization is obtained; performing topological optimization calculation on the finite element model of the air duct, and lightening the finite element model of the air duct according to an optimization result to obtain an air duct model after primary optimization; according to the air duct model after primary optimization, a multi-objective optimization function with the section size and the part wall thickness of the base model after primary optimization as design variables, the original mode of a base, the rigidity of an installation point and the strength under the acceleration load as design constraints and the minimum mass and the maximum flexibility as optimization objectives is constructed, multi-objective optimization is carried out, and a multi-objective optimization result is obtained; and determining the traction fan of the motor vehicle. The lightweight effect and efficiency of the traction fan of the motor vehicle can be improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of structural optimization, and in particular relates to a method, equipment, storage medium and product for lightweighting a traction fan of a power vehicle. Background Art

[0002] High-speed railways have developed rapidly due to their advantages of large transport capacity, high speed, low energy consumption, and environmental protection. Nowadays, as people rely more and more on high-speed trains, the requirements for quality performance and transportation efficiency are also increasing. As a key component of a power train, the lightweight research of traction fans has extremely high research value.

[0003] The research on lightweight traction fans can effectively reduce the weight of the vehicle and extend the driving range. Foreign lightweight research mainly includes:

[0004] Reference 1 (Wang L, Wang T, Luo Y. Improved non-dominated sorting genetic algorithm (NSGA)-II in multi-objective optimization studies of wind turbine blades [J]. Applied Mathematics and Mechanics, 2011, 32: 739-748.) studied a new multi-objective optimization method for turbine blade structure by improving the non-dominated sorting genetic algorithm. The optimization results with maximum power coefficient and minimum blade mass as the objectives showed that the optimization method has good performance in dealing with multi-objective optimization of wind turbine structure.

[0005] Reference 2 (Chen J, Wang Q, Shen WZ, et al. Structural optimization study of composite wind turbine blade [J]. Materials and Design, 2013, 46: 247-255.) uses a combination of finite element analysis and particle swarm optimization to optimize the design of composite wind turbine blades, effectively reducing the mass of the blades.

[0006] Reference 3 (Grujicic M, Arakere G, Pandurangan B, et al. Multidisciplinary design optimization for glass-fiber epoxy-matrix composite 5MW horizontal-axis wind-turbine blades [J]. Journal of Materials Engineering and Performance, 2010, 19 (8): 1116-1127.) adopted the method of structural finite element and life assessment analysis, took the minimum impeller mass as the optimization goal, and took static strength, fatigue life and stiffness as constraints, and carried out multidisciplinary optimization design of the fan impeller, meeting the requirements of lightweight design of the impeller structure;

[0007] Reference 4 (Negm HM, Maalawi K Y. Structural design optimization of windturbine towers [J]. Computers and Structures, 2000, 74 (6): 649-666.) uses five optimization methods to optimize the wind turbine structure, transforms the optimization problem into a nonlinear programming problem, uses the internal penalty function method to solve it, and analyzes the best optimization solution with the objective function of reducing the vibration level.

[0008] Reference 5 (Jureczko M, Pawlak M, A. Optimisation of wind turbine blades[J]. Journal of materials processing technology, 2005, 167(2): 463-471.) conducted a multi-criteria optimization design on the composite blade structure.

[0009] The main research on lightweight design in China is as follows: Reference 6 (Luo Bin, Ding Shuiting, Li Guo. A CAD / CAE integrated method for parametric lightweight turbine disk structure [J]. Journal of Aerospace Power, 2013, 28(09): 2083-2089.) Aiming at the problem of lightweight design of turbine disk structure, the author studied the use of CAD parametric modeling and established a correlation with CAE program to realize an efficient structural optimization design method of turbine disk CAD / CAE automatic integration based on one-way fluid-solid coupling algorithm; Reference 7 (Meng Chunling, Hu Hongliang, Li Guofeng, et al. Strength analysis and optimization design of fan hub based on ANSYS [J]. Computer Simulation, 2012, 29(07): 334-338.) In the study of lightweight design of wind turbine hub, in view of the difficulty of production of traditional variable cross-section design and the lack of fatigue life analysis, a method of reducing the weight of wind turbine hub by drilling holes on the hub body was studied; Reference 8 (Xie Guilan, Xiao Chunya, He Licai. Three-dimensional topological optimization design of composite materials for large wind turbine blades [J]. FRP / Composites, 2015 (6): 53-57.) In view of the problem of lightweight large wind turbine blades, a three-dimensional topological optimization design was carried out on the basis of fiber reinforced composite wind turbine blades; Reference 9 (Wang Quan, Chen Jin, Wang Jun, et al. Structural optimization design of composite wind turbine blades under aerodynamic loads [J]. Journal of Mechanical Engineering Journal of Composite Materials, 2014, 50(09):114-121.) Considering the aerodynamic load, the composite wind turbine blade structure was optimized; Reference 10 (Feng Xiaobing, Huang Hai, Wang Wei. Root strength optimization design of large wind turbine composite blades based on genetic algorithm [J]. Journal of Composite Materials, 2012, 29(05):196-202.) An improved genetic algorithm was used to optimize the ply design of large wind turbine composite blades; Reference 11 (Sun Shunan. Reliability-based optimization design of offshore tripod gantry wind turbine foundation structure [D]. Dalian University of Technology, 2013.) Considered the coefficient of variation and statistical laws of loads, materials and stresses in offshore wind power. , a multi-objective reliability optimization of the wind turbine foundation structure was carried out, and a good optimization design result was obtained; Reference 12 (Lu Qijin, Yang Hezhen. Random dynamic optimization design of offshore wind power support structure [J]. Vibration and Shock, 2013, 32(17): 46-51. DOI: 10.13465 / j.cnki.jvs.2013.17.036.) fully considered the uncertainty factors such as structural size, material, and environmental load. On the basis of orthogonal test and Kriging model technology, a combination of reliability analysis and structural optimization was used to carry out reliability optimization design of wind power structure, which has important reference value for practical engineering problems.

[0010] However, although the above-mentioned technologies for the development of traction fans belong to forward development, they only consider the structural mechanical properties and do not carry out refined lightweight design, resulting in serious local material redundancy. Lightweight design methods such as topology optimization are widely used in automobiles and structural optimization of fan blades, but cannot be simply transplanted to the lightweight design of traction fans in power vehicles. Summary of the invention

[0011] The purpose of the present invention is to provide a traction fan lightweight method, equipment, storage medium and product to solve the problem that traditional methods do not perform refined lightweight design of traction fans, resulting in serious local material redundancy and poor lightweight effect.

[0012] The present invention solves the above technical problems through the following technical solutions: a method for lightweighting a traction fan, the traction fan comprising a base, a wind tube and an air duct, the lightweight method comprising:

[0013] Construct the finite element model of the base;

[0014] Based on the symmetric constraint or the asymmetric constraint, taking the first constraint condition and the maximum bottom flexibility as the objective function, performing a topological optimization calculation on the base finite element model to obtain a first optimization result;

[0015] Lightweighting the base finite element model according to the first optimization result to obtain an optimized base model;

[0016] Construct the finite element model of the wind tube;

[0017] Based on the cyclic symmetry constraint or the axial extrusion constraint, taking the second constraint condition and the maximum flexibility of the wind tube as the objective function, performing topological optimization calculation on the wind tube finite element model to obtain a second optimization result;

[0018] Lightweighting the finite element model of the wind duct according to the second optimization result to obtain a first-optimized wind duct model;

[0019] According to the wind tube model after the primary optimization, a multi-objective optimization function is constructed with the cross-sectional dimensions of the base model after the primary optimization and the wall thickness of all base components as design variables, the original mode of the base, the stiffness of the mounting point and the strength under the acceleration load as design constraints, and the minimum mass and maximum flexibility as optimization targets. Multi-objective optimization is performed to obtain the base model after the secondary optimization.

[0020] The power vehicle traction fan is determined according to the base model after the secondary optimization and the wind tube model after the primary optimization.

[0021] Furthermore, the construction of the base finite element model specifically includes:

[0022] Construct a three-dimensional model of the base according to the outline size of the base;

[0023] Meshing the three-dimensional model of the base to obtain a base mesh model; wherein the base mesh model adopts CTETRA entity units;

[0024] Loads and constraints are applied to the base mesh model to obtain a base finite element model.

[0025] Furthermore, the first constraint condition is that the first-order modal frequency is less than 67.8 Hz and the volume fraction is less than 0.2.

[0026] Further, the base finite element model is lightweighted according to the first optimization result, specifically including:

[0027] According to the first optimization result, vertical reinforcement ribs are designed on the back panel of the base, the side panels of the base are designed as a partial hollow structure, transverse reinforcement ribs or vertical reinforcement ribs are designed on the front wall panel of the base, the supporting feet of the base are designed as square steel supporting feet, and local reinforcements are added to connect the square steel supporting feet and each panel, or the middle of the front support structure is designed as a hollow structure.

[0028] Furthermore, the construction of the finite element model of the wind tube specifically includes

[0029] Construct a three-dimensional model of the wind tube according to the outline size of the wind tube;

[0030] Meshing the three-dimensional model of the wind duct to obtain a wind duct mesh model; wherein the wind duct mesh model adopts a CHEXA hexahedral mesh;

[0031] Loads and constraints are applied to the wind duct mesh model to obtain a wind duct finite element model.

[0032] Furthermore, the second constraint condition is that the first-order modal frequency is greater than 337 Hz; and the volume fraction is less than 0.3.

[0033] Further, the finite element model of the wind tube is lightweighted according to the second optimization result, specifically including:

[0034] According to the second optimization result obtained based on the cyclic symmetry constraint, a grass-head reinforcement is added outside the air duct to reduce the wall thickness of the air duct corresponding to the non-electrical box position;

[0035] According to the second optimization result obtained based on the axial extrusion constraint, the number of vertical reinforcement ribs is increased and the wall thickness of the wind cylinder is reduced.

[0036] Based on the same concept, the present invention also provides an electronic device, including a memory, a processor, and a computer program / instruction stored in the memory, wherein the processor executes the computer program / instruction to implement the traction fan lightweighting method as described above.

[0037] Based on the same concept, the present invention also provides a computer-readable storage medium having a computer program / instruction stored thereon, and when the computer program / instruction is executed by a processor, the traction fan lightweighting method as described above is implemented.

[0038] Based on the same concept, the present invention also provides a computer program product, including a computer program / instruction, which implements the above-mentioned method for lightweighting a traction fan when executed by a processor.

[0039] Beneficial Effects

[0040] Compared with the prior art, the advantages of the present invention are:

[0041] According to the finite element model of the base, the present invention performs topological optimization calculation based on symmetric constraints or asymmetric constraints, with the first constraint condition and the maximum flexibility of the base as the objective function of the base, and obtains the first optimization result; according to the finite element model of the wind tube, based on the cyclic symmetric constraint or the axial extrusion constraint, with the second constraint condition and the maximum flexibility of the wind tube as the objective function of the wind tube, the topological optimization calculation is performed to obtain the second optimization result; according to the optimized wind tube model, the cross-sectional dimensions and part wall thickness of the optimized base model are established as design variables, the original mode of the base, the stiffness of the mounting point, and the strength under the acceleration load are used as design constraints, and the minimum mass and the maximum flexibility are used as optimization targets, and multi-objective optimization is performed; the present invention adopts the idea of ​​reverse development to optimize the base and the wind tube to obtain a lightweight base and wind tube; by iterating the objective function, the efficiency of the overall design is improved. The present invention can improve the effect and efficiency of lightweighting of the traction fan of the power vehicle. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] In order to more clearly illustrate the technical solution of the present invention, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only one embodiment of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0043] Figure 1 is a flow chart of a method for lightweighting a traction fan in an embodiment of the present invention;

[0044] Figure 2 is a finite element model of a base in an embodiment of the present invention;

[0045] Figure 3is the first optimization result under the symmetry constraint and working condition S2 in the embodiment of the present invention;

[0046] Figure 4 is the first optimization result under the asymmetric constraint and working condition S2 in the embodiment of the present invention;

[0047] Figure 5 is a schematic diagram of a base back panel designed with vertical reinforcing ribs obtained based on a first optimization result under symmetry constraints in an embodiment of the present invention;

[0048] Figure 6 is a schematic diagram of a partially hollowed-out side panel of a base obtained based on a first optimization result under symmetry constraints in an embodiment of the present invention;

[0049] Figure 7 is a schematic diagram of a base front wall panel designed with transverse reinforcing ribs obtained based on a first optimization result under symmetry constraints in an embodiment of the present invention;

[0050] Figure 8 is a schematic diagram of a square steel support foot obtained based on the first optimization result under symmetry constraints in an embodiment of the present invention;

[0051] Fig. 9 is a schematic diagram of a base after an optimization based on a first optimization result under a symmetry constraint in an embodiment of the present invention;

[0052] Fig.10 is a schematic diagram of a base back panel designed with vertical reinforcing ribs obtained based on a first optimization result under asymmetric constraints in an embodiment of the present invention;

[0053] Fig.11 is a schematic diagram of a partially hollowed-out side panel of a base obtained based on a first optimization result under asymmetric constraints in an embodiment of the present invention;

[0054] Fig.12 is a schematic diagram of a front wall panel designed with vertical stiffeners obtained based on the first optimization result under asymmetric constraints in an embodiment of the present invention;

[0055] Fig.13 is a schematic diagram of a hollow front support structure obtained based on a first optimization result under an asymmetric constraint in an embodiment of the present invention;

[0056] Fig.14 is a schematic diagram of a rear end sheet metal part with a cavity structure obtained based on a first optimization result under asymmetric constraints in an embodiment of the present invention;

[0057] Fig.15 is a schematic diagram of a base after an optimization based on a first optimization result under an asymmetric constraint in an embodiment of the present invention;

[0058] Fig.16 is a finite element model of a wind tube in an embodiment of the present invention;

[0059] Fig.17 is a schematic diagram of a wind tube obtained based on the second optimization result under the cyclic symmetry constraint in an embodiment of the present invention;

[0060] Fig.18 is a schematic diagram of an optimized wind tunnel obtained based on the second optimization result under the cyclic symmetry constraint in an embodiment of the present invention;

[0061] Fig.19 Schematic diagram of an original air duct with four vertical reinforcing ribs in an embodiment of the present invention;

[0062] Fig. 20 is a schematic diagram of a wind tube obtained based on a second optimization result under axial extrusion constraint in an embodiment of the present invention;

[0063] Fig.21 is a schematic diagram of an optimized wind tube obtained based on the second optimization result under axial extrusion constraint in an embodiment of the present invention;

[0064] Fig. 22 is a multi-objective optimization result of the front support structure of the base in an embodiment of the present invention;

[0065] Fig.23 is a multi-objective optimization result of the side panel of the base in an embodiment of the present invention;

[0066] Fig.24 is an optimized traction fan in an embodiment of the present invention;

[0067] Fig.25 is a stress cloud diagram of the guide vane weld in an embodiment of the present invention;

[0068] Fig.26 It is a stress cloud diagram of the rib plate weld in the embodiment of the present invention.

[0069] Explanation of the accompanying drawings: 1-base, 11-back panel, 12-front support structure, 13-front wall panel, 14-rear support structure, 15-body mounting plate, 16-front support plate, 2-air cylinder, 21-cylinder body, 22-grass-head reinforcement, 23-vertical reinforcement rib, 24-lower flange, 3-air duct. DETAILED DESCRIPTION

[0070] The following is a clear and complete description of the technical solutions in the present invention in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0071] The technical solution of the present application is described in detail with specific embodiments below. The following specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described in detail in some embodiments.

[0072] Example 1

[0073] The power vehicle traction fan includes a base 1, a wind tube 2 and an air duct 3 (such as Fig.24 As shown), the wind tube includes a motor, an impeller, a sealing ring, etc., and each component is fixed by bolts, plug-ins and crimping.

[0074] Figure 1 The flowchart of the lightweight method of the traction fan provided by the present invention is shown as follows: Figure 1 As shown, the lightweighting method of the traction fan comprises the following steps:

[0075] Step 1: Construct the finite element model of the base.

[0076] In a specific embodiment of the present invention, the specific implementation process of constructing the base finite element model includes:

[0077] Step 1.1: Construct a 3D model of the base according to the outline dimensions of the base.

[0078] Step 1.2: Mesh the three-dimensional model of the base to obtain a base mesh model.

[0079] The three-dimensional model of the base is meshed based on Hypermesh software. In this embodiment, the base mesh model uses CTETRA entity units, the mesh size is 2 mm, the number of units of the entire base mesh model is about 4.187 million, and the number of nodes is about 847,000.

[0080] Step 1.3: Apply loads and constraints to the base mesh model to obtain the base finite element model, such as Figure 2 shown. Figure 2 In the figure, the installation position of the wind tube on the upper surface of the base is the non-design area, and the rest is the design area (i.e., the blue area). The external nodes of the non-design area are coupled to the center of the area, and the center of the area is used as the load loading point of the base to constrain the 1-6 degrees of freedom (i.e., translation and rotation in the XYZ direction) of the connection area between the bottom of the base and the floor. The coordinate system in this embodiment is the vehicle coordinate system of the power vehicle (i.e., the global coordinate system). The load conditions of the base are shown in Table 1.

[0081] Table 1 Load conditions of the base

[0082]

[0083] In Table 1, m represents mass, and g represents gravitational acceleration.

[0084] Step 2: Based on the symmetric constraint or the asymmetric constraint, taking the first constraint condition and the maximum bottom flexibility as the objective function, a topological optimization calculation is performed on the base finite element model to obtain a first optimization result.

[0085] The finite element model of the base is subjected to topology optimization calculation in the Optistruct section of the HyperWorks software, and the first optimization result obtained is the load transfer path of the base. In this embodiment, the first constraint condition is that the first-order modal frequency is less than 67.8 Hz and the volume fraction is less than 0.2. By comparison, the first optimization result under the working condition S2 in Table 1 is more effective, such as Figure 3 and Figure 4 As shown. Figure 3 and Figure 4 It can be seen that after adding the symmetry constraint, the first optimization result cloud map has good symmetry, which has great reference value for the subsequent lightweighting of the base.

[0086] Step 3: Lighten the finite element model of the base according to the first optimization result to obtain an optimized base model.

[0087] In a specific embodiment of the present invention, according to the first optimization result obtained based on the symmetry constraint and the working condition S2, the finite element model of the base is lightweighted:

[0088] According to the first optimization result based on symmetry constraint and working condition S2, a rib structure appears on the back panel of the base. Therefore, vertical reinforcement ribs are designed on the back panel of the base, such as Figure 5 As shown in FIG. 1 , a hollow structure appears on the side of the base, so the side panel of the base is designed as a partial hollow structure, that is, part of the material of the side panel of the base is removed, such as Figure 6 As shown in the figure, there is an obvious rib structure on the front wall of the base, so transverse reinforcement ribs are designed on the front wall panel of the base, such as Figure 7 As shown;

[0089] According to the first optimization result based on symmetry constraint and working condition S2, the main load transfer path is the front and rear four support feet. Therefore, the lightweight design only strengthens this transfer path. The four support feet of the base are designed as square steel support feet, and local reinforcements are added to connect the square steel support feet and each panel, such as Figure 8 According to the first optimization result based on symmetry constraint and working condition S2, the final design scheme of the base is as follows Fig. 9 As shown, the base mass has been reduced from 81kg to 51.1kg, a weight reduction of 29.9kg.

[0090] In another specific embodiment of the present invention, according to the first optimization result obtained based on the asymmetric constraint and the working condition S2, the finite element model of the base is lightweighted:

[0091] According to the first optimization result obtained based on the asymmetric constraint and working condition S2, a rib structure appears on the back panel 11 of the base 1. Therefore, the original integrated structure is split and vertical reinforcement ribs are designed on the back panel 11 of the base 1, such as Fig.10 As shown; the side panel of the base 1 is designed to be a partially hollow structure, that is, part of the material of the side panel of the base 1 is removed, such as Fig.11 As shown; a cross rib structure appears on the front wall of the base 1, so vertical reinforcement ribs are designed on the front wall panel 13 of the base 1 to improve its vertical bearing capacity, such as Fig.12 As shown;

[0092] According to the first optimization result obtained based on the asymmetric constraint and working condition S2, the main load transmission path is the front and rear four support legs, and the middle of the front support structure 12 is hollow. Therefore, the lightweight design only strengthens this transmission path and designs the middle of the front support structure 12 into a hollow structure, such as Fig.13 As shown; on the basis of the rear end sheet metal structure, front and rear reinforcements are added, and the rear end sheet metal forms a cavity structure to improve the cross-sectional rigidity, as shown Fig.14 According to the first optimization result based on the asymmetric constraint and working condition S2, the final design scheme of the base is as follows Fig.15 As shown, the base mass is 54.5kg, which is 26.5kg lighter than the initial mass.

[0093] Step 4: Construct the finite element model of the wind tube.

[0094] In a specific embodiment of the present invention, a finite element model of a wind tube is constructed, specifically comprising

[0095] Step 4.1: Construct a three-dimensional model of the wind duct according to the outline dimensions of the wind duct.

[0096] Step 4.2: Mesh the three-dimensional model of the wind duct to obtain a wind duct mesh model.

[0097] The wind duct three-dimensional model is meshed based on Hypermesh software. In this embodiment, the wind duct mesh model uses CHEXA hexahedral mesh, and the number of cells and nodes of the entire wind duct mesh model is about 1.553 million and about 1.731 million, respectively.

[0098] Step 4.3: Apply loads and constraints to the wind duct mesh model to obtain the wind duct finite element model.

[0099] like Fig.16As shown in the figure, the interior and installation area of ​​the wind duct are set as non-design areas (i.e., gray areas), and the exterior is set as design areas (i.e., yellow areas). The bolt holes on the upper surface of the wind duct are coupled to a central point, which is used as the load loading point of the upper end of the wind duct (applying mass m1); the blade edge inside the wind duct is coupled to a central point, which is used as the motor load loading point (applying motor mass m2); the 1-6 degrees of freedom of the bolt mounting holes on the lower surface are constrained (i.e., translation and rotation in the XYZ direction). The load loading conditions of the load loading point of the upper end of the wind duct are shown in Table 1. Two schemes, cyclic symmetry constraint (period of 8) and axial extrusion constraint, are adopted. In condition S1, the displacement of the load loading point of the upper end of the wind duct is less than 0.0053mm, and the displacement of the lower end coupling point (i.e., the lower surface bolt mounting hole is coupled to a central point) is less than 0.0368mm; in condition S2, the displacement of the load loading point of the upper end of the wind duct is less than 0.0186mm, and the displacement of the lower end coupling point is less than 0.0153mm.

[0100] Step 5: Based on the cyclic symmetry constraint or the axial extrusion constraint, with the second constraint condition and the maximum flexibility of the wind duct as the objective function, a topological optimization calculation is performed on the finite element model of the wind duct to obtain the second optimization result.

[0101] The finite element model of the wind tube is subjected to topology optimization calculation in the Optistruct section of the HyperWorks software, and the second optimization result obtained is the load transfer path of the wind tube. In this embodiment, the second constraint condition is that the first-order modal frequency is greater than 337 Hz; and the volume fraction is less than 0.3.

[0102] Step 6: According to the second optimization result, the finite element model of the wind duct is lightweighted to obtain a wind duct model after primary optimization.

[0103] In a specific embodiment of the present invention, the finite element model of the wind tube is lightweighted according to the second optimization result obtained based on the cyclic symmetry constraint:

[0104] According to the second optimization result obtained based on the cyclic symmetry constraint, three grass-head reinforcement members 22 with a thickness of 0.7 mm are added to the outside of the air duct body 21, and the wall thickness of the air duct body 21 corresponding to the non-electrical box position is reduced from the original 4 mm to 3 mm (that is, avoiding the electrical box position, reducing the wall thickness of the air duct body 21 from 4 mm to 3 mm), such as Fig.17 According to the second optimization result based on the cyclic symmetry constraint, the final design of the wind tube is as follows: Fig.18 As shown in the figure, the mass of the hair dryer is reduced from 20.06kg to 16.56kg, a weight reduction of 3.5kg.

[0105] In another specific embodiment of the present invention, according to the second optimization result obtained based on the axial extrusion constraint, the finite element model of the wind tube is lightweighted:

[0106] According to the second optimization result based on the axial extrusion constraint, the vertical reinforcement ribs are evenly distributed. Therefore, the original four vertical reinforcement ribs 23 (such as Fig.19 As shown in FIG. 1 ), the number of roots is increased to 8 and evenly distributed according to the topological position of the second optimization result, as shown in FIG. Fig. 20 As shown, the wall thickness of the wind tube is reduced from the original 4mm to 3mm. According to the second optimization result based on the axial extrusion constraint, the final design of the wind tube is as follows: Fig.21 As shown in the figure, the mass of the hair dryer is reduced from 20.06kg to 17.08kg, a weight reduction of 2.26kg.

[0107] Step 7: Based on the wind duct model after the first optimization, construct a multi-objective optimization function with the cross-sectional dimensions of the first optimized base model and the wall thickness of all base components as design variables, the original mode of the base, the stiffness of the mounting point and the strength under acceleration load as design constraints, and the minimum mass and maximum flexibility as optimization goals. Perform multi-objective optimization to obtain the base model after the second optimization.

[0108] like Fig. 22 and Fig.23 As shown in the figure, the mass of the base model after secondary optimization is reduced to 50.44 kg, achieving a weight reduction of 30.56 kg.

[0109] Step 8: Determine the power vehicle traction fan based on the secondary optimized base model and the primary optimized wind tunnel model.

[0110] The performance parameters of the various components of the power vehicle traction fan obtained by the present invention are shown in Table 2.

[0111] Table 2 Performance parameters of various components of traction fan

[0112]

[0113] According to the structural requirements of railway application-track body, the basic performance analysis of the traction fan, such as constrained modal, static strength and weld fatigue strength, is carried out, and the 1-6 degrees of freedom of the traction fan air duct inlet and the connection position between the base and the floor are constrained. According to relevant standards, the static strength analysis and weld fatigue strength analysis need to load the gravity acceleration in the three directions of XYZ, and the loading conditions are shown in Tables 3 and 4.

[0114] Table 3 Loading conditions for static strength analysis

[0115] Load Cases X direction Y direction Z direction S1 \ \ -3g S2 \ \ 1g S3 3g \ -1g S4 -3g \ -1g S5 \ 1g -1g S6 \ -1g -1g

[0116] Table 4 Loading conditions for weld fatigue strength analysis

[0117]

[0118]

[0119] According to the fourth strength theory: the square root shear stress generated on the unit body is the main cause of the yield failure of the material. No matter what the stress state is, if it is equal to the material limit value, yield failure will occur. Plastic deformation or material failure of the material indicates structural failure. Strength represents the ability of the traction fan to resist damage under external forces, which must be met during the structural design process. In order for the traction fan to operate normally, it must be ensured that the maximum stress of all parts of the vehicle body under each working condition is less than the allowable stress of its material.

[0120] The conditions for the traction fan structure to not fail due to the stress generated by the load applied under various working conditions are:

[0121]

[0122] Where: ε is the equivalent stress, [σ] is the allowable stress of the material; σ1, σ2, σ3 are the first, second, and third principal stresses respectively, [σ] = σ s / n,σ s It represents the yield strength of the material, n is the safety factor, and its value is 1.15.

[0123] The calculation results of the first six modal states of the traction fan are shown in Table 5, and Table 6 is the static strength analysis results of the fan. It can be seen from Table 6 that the safety factors of various components of the traction fan are within the safety range under different working conditions. The fan welds are mainly composed of two parts: the guide vane welds and the rib plate welds. Table 7 shows the calculation results of the fatigue allowable values ​​and load ratios of the fan welds. It can be seen from Table 7 that the longitudinal, vertical normal stresses and longitudinal shear forces of the fan guide vane welds and rib plate welds are qualified, the weld load state is low, the safety requirement level is medium, and the weld quality level is CPC3.

[0124] Table 5 Calculation results of the first six modes of traction fans

[0125] Order 1 2 3 4 5 6 Frequency(HZ) 45.56 50.54 61.93 66.85 69.64 76.49

[0126] Table 6 Fan static strength analysis results

[0127]

[0128] Table 7 Calculation results of allowable fatigue values ​​and load ratios of fan welds

[0129]

[0130] According to the above optimization results, the traction fan is optimized. The base is lightweighted by using the first optimized structure obtained based on asymmetric constraints, and the wind tube is lightweighted by using the second optimized structure obtained based on cyclic symmetric constraints. The final optimization model of the traction fan is as follows: Fig.24 As shown in the figure, a total weight reduction of 34.06kg was achieved. The thickness of the optimized traction fan structure has changed. In order to verify the rationality and correctness of the optimization scheme, it is necessary to check the static strength and fatigue strength of the traction fan after optimization and perform modal analysis to determine whether the strength and stiffness of the fan structure after optimization meet the requirements.

[0131] The constrained modal check of the traction fan is carried out to constrain the 1-6 degrees of freedom of the fan air duct outlet, the base and the floor connection position, and the first six constrained modes are calculated. From the calculation results in Table 5, it can be seen that the natural frequency of the optimized traction fan model is significantly improved, which can effectively avoid the resonance phenomenon caused by external excitation.

[0132] As shown in Table 6, the safety factors of all components of the traction fan are within the safety range and are significantly improved compared with the safety factors of the original model.

[0133] It can be seen from Table 7 that the longitudinal, vertical normal stress and longitudinal shear force of the guide vane weld and rib weld of the traction fan are qualified, the weld load state is low, the safety requirement level is medium, and the weld quality level is CPC3. Fig.25 and Fig.26 They are the stress cloud diagrams of the guide vane weld and the rib weld, Fig.25 and Fig.26 The numbers on the middle cylinder indicate the corresponding stress values, e.g. Fig.25 The number 3.15 on the cylinder in the Y-direction maximum normal stress cloud diagram indicates the location and specific value of the maximum normal stress in the Y-direction.

[0134] Based on the original traction fan model, topology optimization and multi-objective optimization were carried out. According to the optimization results, the traction fan optimization model was designed and manufactured. Compared with the original model, the optimized model achieved a weight reduction of 34.06kg, with a weight reduction ratio of 12.69%, achieving the lightweight design goal. Under the premise of achieving weight reduction, the basic performance of the traction fan optimization model, such as constraint mode, static strength and weld fatigue strength, all met the requirements, and were significantly improved compared with the original model. The traction fan was manufactured according to the traction fan optimization model, and relevant performance tests were carried out. The test results met the design and use requirements.

[0135] Example 2

[0136] An embodiment of the present invention further provides an electronic device, which includes: a memory, a processor, and a computer program / instructions stored in the memory, and the processor executes the computer program / instructions to implement the traction fan lightweighting method in the embodiment of the present application.

[0137] Although not shown, the electronic device includes a processor, which can perform various appropriate operations and processes according to the program and / or data stored in the read-only memory (ROM) or the program and / or data loaded from the storage portion into the random access memory (RAM). The processor can be a multi-core processor, or it can include multiple processors. In some embodiments, the processor can include a general main processor and one or more special coprocessors, such as a central processing unit, a graphics processing unit (GPU), a neural network processor (NPU), a digital signal processor (DSP), etc. In RAM, various programs and data required for device operation are also stored. The processor, ROM and RAM are connected to each other via a bus. The input / output (I / O) interface is also connected to the bus.

[0138] The processor and the memory are used together to execute the program / instructions stored in the memory. When the program / instructions are executed by the computer, the methods, steps or functions described in the above embodiments can be implemented.

[0139] Although not shown, an embodiment of the present invention further provides a computer-readable storage medium on which a computer program / instruction is stored. When the computer program / instruction is executed by a processor, the method for lightweighting the traction fan in the embodiment of the present application is implemented.

[0140] Readable storage media include permanent and non-permanent, removable and non-removable media that can be implemented by any method or technology to store information. Information can be computer-readable instructions, data structures, program modules or other data. Examples of computer storage media include, but are not limited to, phase change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technology, compact disk read-only memory (CD-ROM), digital versatile disk (DVD) or other optical storage, magnetic cassettes, disk storage or other magnetic storage devices or any other non-transmission media that can be used to store information that can be accessed by a computing device. As defined herein, computer-readable media does not include temporary computer-readable media (transitory media), such as modulated data signals and carrier waves.

[0141] Although not shown, an embodiment of the present invention further provides a computer program product, including: a computer program / instruction, which, when executed by a processor, implements the lightweighting method of the traction fan in the embodiment of the present application.

[0142] What is disclosed above is only a specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can easily think of changes or modifications within the technical scope disclosed in the present invention, which should be covered within the protection scope of the present invention.

Claims

1. A method for lightweighting a traction fan, the traction fan comprising a base, a wind tube and an air duct, characterized in that: The lightweight method comprises: Construct the finite element model of the base; Based on the symmetric constraint or the asymmetric constraint, taking the first constraint condition and the maximum bottom flexibility as the objective function, performing a topological optimization calculation on the base finite element model to obtain a first optimization result; Lightweighting the base finite element model according to the first optimization result to obtain a base model after primary optimization; Construct the finite element model of the wind tube; Based on the cyclic symmetry constraint or the axial extrusion constraint, taking the second constraint condition and the maximum flexibility of the wind tube as the objective function, performing topological optimization calculation on the wind tube finite element model to obtain a second optimization result; Lightweighting the finite element model of the wind duct according to the second optimization result to obtain a first-optimized wind duct model; According to the wind tube model after the primary optimization, a multi-objective optimization function is constructed with the cross-sectional dimensions of the base model after the primary optimization and the wall thickness of all base components as design variables, the original mode of the base, the stiffness of the mounting point and the strength under the acceleration load as design constraints, and the minimum mass and maximum flexibility as optimization targets. Multi-objective optimization is performed to obtain the base model after the secondary optimization. The power vehicle traction fan is determined according to the base model after the secondary optimization and the wind tube model after the primary optimization.

2. The method for lightweighting a traction fan according to claim 1, characterized in that: The construction of the base finite element model specifically includes: Construct a three-dimensional model of the base according to the outline size of the base; Meshing the three-dimensional model of the base to obtain a base mesh model; wherein the base mesh model adopts CTETRA entity units; Loads and constraints are applied to the base mesh model to obtain a base finite element model.

3. The method for lightweighting a traction fan according to claim 1, characterized in that: The first constraint condition is that the first-order modal frequency is less than 67.8 Hz and the volume fraction is less than 0.

2.

4. The method for lightweighting a traction fan according to claim 1, characterized in that: Lightweighting the base finite element model according to the first optimization result specifically includes: According to the first optimization result, vertical reinforcement ribs are designed on the back panel of the base, the side panels of the base are designed as a partial hollow structure, transverse reinforcement ribs or vertical reinforcement ribs are designed on the front wall panel of the base, the supporting feet of the base are designed as square steel supporting feet, and local reinforcements are added to connect the square steel supporting feet and each panel, or the middle of the front support structure is designed as a hollow structure.

5. The method for lightweighting a traction fan according to claim 1, characterized in that: The construction of the wind tube finite element model specifically includes Construct a three-dimensional model of the wind tube according to the outline size of the wind tube; Meshing the three-dimensional model of the wind duct to obtain a wind duct mesh model; wherein the wind duct mesh model adopts a CHEXA hexahedral mesh; Loads and constraints are applied to the wind duct mesh model to obtain a wind duct finite element model.

6. The method for lightweighting a traction fan according to claim 1, characterized in that: The second constraint condition is that the first-order modal frequency is greater than 337 Hz; and the volume fraction is less than 0.

3.

7. The method for lightweighting a traction fan according to claim 1, characterized in that: The finite element model of the wind tube is lightweighted according to the second optimization result, specifically comprising: According to the second optimization result obtained based on the cyclic symmetry constraint, a grass-head reinforcement is added outside the air duct to reduce the wall thickness of the air duct corresponding to the non-electrical box position; According to the second optimization result obtained based on the axial extrusion constraint, the number of vertical reinforcement ribs is increased and the wall thickness of the wind cylinder is reduced.

8. An electronic device comprising a memory, a processor, and a computer program / instruction stored in the memory, characterized in that: The processor executes the computer program / instructions to implement the lightweighting method for a traction fan according to any one of claims 1 to 7.

9. A computer-readable storage medium having a computer program / instruction stored thereon, characterized in that: When the computer program / instructions are executed by a processor, the method for lightweighting a traction fan according to any one of claims 1 to 7 is implemented.

10. A computer program product comprising a computer program / instructions, characterized in that When the computer program / instructions are executed by a processor, the method for lightweighting a traction fan according to any one of claims 1 to 7 is implemented.

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