Finite element calculation method for abrasion of main parts of output stage of NGW type wind power speed reducer

Abstract

The invention discloses a finite element calculation method for abrasion of main parts of an output stage of an NGW type wind power speed reducer, relates to the field of NGW type gear speed reducers, and aims at achieving the abrasion loss under the condition of full-design-life operation loads. According to the finite element calculation method for the abrasion of the main parts of the output stage of the NGW type wind power speed reducer, a topological optimization method Optimization module and a response surface method Parameter module are used, and the structure size of an abrasion-resistant part is optimized; the bearing roller is in standard friction contact with the inner ring and the outer ring; building corresponding properties of the anisotropic elastic material and the bilinear isotropic hardened material by using relatively relevant material test data; an Archard theory is used for building a solving calculation model of the starting abrasion loss; reducing the contact permeation value in the frictional contact to be less than e-4, and calculating to obtain a normal stiffness value in the contact setting; and the simulation result is optimized again by utilizing grid independence, and the total wear volume is calculated in the sub-model.

Description

Technical Field

[0001] The invention relates to the technical field of NGW type gear reducers for wind turbines, and in particular to a finite element calculation method for wear of main parts of an output stage of an NGW type wind turbine reducer. Background Art

[0002] With the vigorous promotion of clean and renewable energy in recent years, the power generation of wind turbines has also undergone a qualitative change, from small onshore models such as those below 1MW to large models of 5-10MW, and 10-20MW have been successfully installed at sea.

[0003] As the power increases, the load-bearing capacity of the reducer is required to be higher, the internal lubrication capacity is required to be higher, and more attention is paid to the failure of the internal structure due to wear. Regarding the problem of wear, after the development in recent years, a lot of scientific research results have been achieved, and there are many professional articles and experience estimation methods, which have played a role in promoting the optimization of products.

[0004] However, long-periodic contact wear intensifies the wear of wear-resistant baffles, wear-resistant gaskets and NGW planetary gear trains, resulting in a reduction in the life of mechanical products. In severe cases, it leads to breakage and transmission failure. Therefore, in order to increase the service life of friction pairs, we urgently need a more accurate calculation method that can more intuitively use numbers to reflect the amount of wear. Based on the experience of predecessors, the degree of wear is expressed in adjectives and converted into specific digital volume values ​​or digital values ​​in the thickness direction.

[0005] In other words, how to provide a finite element calculation method for the wear of the main parts of the output stage of an NGW-type wind turbine reducer, which can achieve more precise control of the surface hardness value of the wear-resistant parts and optimize the lubrication method of the gear train, has become a technical problem that technical personnel in this field urgently need to solve. Summary of the invention

[0006] The purpose of the present invention is to provide a finite element calculation method for the wear of the main parts of the output stage of an NGW type wind power reducer. The method is based on ANSYS-Workbench software, optimizes the design model and then performs wear simulation calculations. After the actual contact model is built to complete a cycle of operation, the APDL command stream is used to implement Archard's theoretical logic, thereby achieving the calculation of the wear of the main anti-wear parts of the planetary frame of the NGW type wind power reducer.

[0007] In order to achieve the above object, the present invention adopts the following technical scheme: A finite element calculation method for the wear of the main parts of the output stage of an NGW type wind power reducer, comprising: Based on the previous design model, the topology optimization method Optimization module and the response surface method Parameter module are used to optimize the structural dimensions of the main wear-resistant parts to achieve the relatively optimal state of deformation and stress, and determine the optimal numerical model for wear simulation input; The model is simplified to reduce the simulation calculation time while ensuring the simulation accuracy; the simplification is based on the understanding of Saint-Venant's principle, that is, the chamfers or small features that do not bear force are deleted; the model is truncated based on the principle of 10 times the stiffness or mass, and the simulation model is built using fixed supports; for the simplified finite element simulation model of the transient structural module of the NGW type gear output stage, the simplification of the bearing model is particularly important in this simulation model, and a real roller model is used, but the cage between the rollers is simplified to use small thin sheets to connect all the rollers; a real bearing physical model is used, and standard friction contact is used between the bearing rollers and the inner and outer rings to improve the simulation accuracy; this model is a simulation sub-model, which is a simulation model for calculating the wear of wear-resistant gaskets and wear-resistant baffles Since it involves nonlinear calculation, material nonlinearity is now taken into account, and the corresponding anisotropic elastic material and bilinear isotropic hardening material properties are constructed using more relevant material test data; Standard friction contact is adopted. In the overall model simulation analysis, the designed assembly clearance and interference are considered. In the connection relationship between the full model and the sub-model, the APDL command flow method is used. The Archard theory is used to build a calculation model for the startup wear amount, which includes parameters such as sliding index, pressure index, wear coefficient, and material hardness. In order to calculate the wear amount more accurately, the contact penetration value in the friction contact is reduced to e -4 Below, the normal stiffness value in the contact setting is obtained using theoretical calculations; In order to control the simulation accuracy and adjust the contact error, a high-order hexahedral mesh was used, and all model meshes used solid186; According to the actual physical model, the sun gear is loaded with torque and speed, and the outer ring gear is fixedly supported; In order to ensure the accuracy of the simulation, in the calculation of the transient structural module of the whole machine, first ensure that the structure rotates for one cycle and judge that the contact penetration value is less than e -4 Finally, debug the result after the sub-model rotates for one cycle. When the two results are basically the same, it proves that there is no problem with the sub-model. Then use the sub-model to complete the wear simulation of the entire life cycle. Secondly, use the contact tool to infer whether the force on the NGW gear is correct. Finally, use the grid independence to optimize the simulation results again, and finally calculate the total wear volume in the sub-model.

[0008] Among them, the thickness of the thin film is determined by using a separate bearing model to perform a simple loading simulation. After simulation testing, it is determined that the thin film connecting the roller does not bring in excess stiffness, and the impact on the overall simulation is negligible.

[0009] Specifically, the theoretical empirical formula includes: normal contact force, contact stiffness, penetration, exponential coefficient of force, damping coefficient, and normal relative velocity of the contact point.

[0010] Compared with the prior art, the finite element calculation method for the wear of the main parts of the output stage of the NGW type wind power reducer described in the present invention has the following advantages: In the finite element calculation method for the wear of the main parts of the output stage of the NGW type wind power reducer provided by the present invention, based on the Transient Structural module in the ANSYS-Workbench software, an actual contact model is built, and the main parameters such as the contact stiffness are determined according to theoretical calculations to achieve a good simulated contact state and a contact penetration tolerance less than e -4 , and use the APDL command stream to implement Archard's theoretical logic. After completing multiple cycles of operation, the simulation sub-model construction method of the main wear parts can be obtained, and the sub-model technology is used to simulate the wear amount under full life cycle conditions, thereby greatly improving the simulation design time; after debugging several cycles of the full model, it is found that the wear amount and the wear amount of the sub-model are the same, and it is believed that the truncation and construction of the constructed sub-model simulation model meet the actual requirements, and then the wear amount under the full design life operating load is realized through the sub-model method, which improves the simulation efficiency, and the calculation method of the wear amount of the main anti-wear parts of the NGW type wind power reducer is specified in detail.

[0011] In other words, the finite element calculation method for the wear of the main parts of the output stage of the NGW type wind power reducer provided by the present invention is based on the Transient Structural module in the ANSYS-Workbench software to realize the transient dynamic simulation method. In order to save simulation working time and improve efficiency, a sub-model is used to realize the full life simulation method. After the solution is completed, the command stream is used to extract the wear volume and calculate the thickness value. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 A schematic flow chart of a finite element calculation method for wear of main parts of an output stage of an NGW-type wind power reducer provided in an embodiment of the present invention; Figure 2 A simulation result diagram of the wear amount of components under one cycle load in the finite element calculation method for the wear of the main components of the output stage of the NGW type wind power reducer provided in an embodiment of the present invention; Figure 3A result diagram of the contact penetration error value of components under one cycle load in the finite element calculation method for the wear of the main components of the output stage of the NGW type wind power reducer provided in an embodiment of the present invention; Figure 4 A result diagram of the full life wear of a sub-model in the finite element calculation method for the wear of the main parts of the output stage of the NGW type wind power reducer provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0013] For ease of understanding, the finite element calculation method for the wear of the main parts of the output stage of the NGW type wind power reducer provided by the embodiment of the present invention is described in detail below in conjunction with the accompanying drawings of the specification.

[0014] The embodiment of the present invention provides a finite element calculation method for the wear of the main parts of the output stage of an NGW type wind power reducer, such as Figure 1-Figure 4 As shown, including: Based on the previous design model, the topology optimization method Optimization module and the response surface method Parameter module are used to optimize the structural dimensions of the main wear-resistant parts to achieve the relatively optimal state of deformation and stress, and determine the optimal numerical model for wear simulation input; The model is simplified to reduce the simulation calculation time while ensuring the simulation accuracy; the simplification is based on the understanding of Saint-Venant's principle, that is, the chamfers or small features that do not bear force are deleted; the model is truncated based on the principle of 10 times the stiffness or mass, and the simulation model is built using fixed supports; for the simplified finite element simulation model of the transient structural module of the NGW type gear output stage, the simplification of the bearing model is particularly important in this simulation model, and a real roller model is used, but the cage between the rollers is simplified to use small thin sheets to connect all the rollers; a real bearing physical model is used, and standard friction contact is used between the bearing rollers and the inner and outer rings to improve the simulation accuracy; this model is a simulation sub-model, which is a simulation model for calculating the wear of wear-resistant gaskets and wear-resistant baffles Since it involves nonlinear calculation, material nonlinearity is now taken into account, and the corresponding anisotropic elastic material and bilinear isotropic hardening material properties are constructed using more relevant material test data; Standard friction contact is adopted. In the overall model simulation analysis, the designed assembly clearance and interference are considered. In the connection relationship between the full model and the sub-model, the APDL command flow method is used. The Archard theory is used to build a calculation model for the startup wear amount, which includes parameters such as sliding index, pressure index, wear coefficient, and material hardness. In order to calculate the wear amount more accurately, the contact penetration value in the friction contact is reduced to e -4 Below, the normal stiffness value in the contact setting is obtained using theoretical calculations; In order to control the simulation accuracy and adjust the contact error, a high-order hexahedral mesh was used, and all model meshes used solid186; According to the actual physical model, the sun gear is loaded with torque and speed, and the outer ring gear is fixedly supported; In order to ensure the accuracy of the simulation, in the calculation of the transient structural module of the whole machine, first ensure that the structure rotates for one cycle and judge that the contact penetration value is less than e -4 Finally, debug the result after the sub-model rotates for one cycle. When the two results are basically the same, it proves that there is no problem with the sub-model. Then use the sub-model to complete the wear simulation of the entire life cycle. Secondly, use the contact tool to infer whether the force on the NGW gear is correct. Finally, use the grid independence to optimize the simulation results again, and finally calculate the total wear volume in the sub-model.

[0015] Compared with the prior art, the finite element calculation method for the wear of the main parts of the output stage of the NGW type wind power reducer described in the embodiment of the present invention has the following advantages: In the finite element calculation method for the wear of the main parts of the output stage of the NGW type wind power reducer provided in the embodiment of the present invention, based on the Transient Structural module in the ANSYS-Workbench software, an actual contact model is built, and the main parameters such as the contact stiffness are determined according to theoretical calculations to achieve a good simulated contact state and a contact penetration tolerance less than e -4 , and use the APDL command stream to implement Archard's theoretical logic. After completing multiple cycles of operation, the simulation sub-model construction method of the main wear parts can be obtained, and the sub-model technology is used to simulate the wear amount under full life cycle conditions, thereby greatly improving the simulation design time; after debugging several cycles of the full model, it is found that the wear amount and the wear amount of the sub-model are the same, and it is believed that the truncation and construction of the constructed sub-model simulation model meet the actual requirements, and then the wear amount under the full design life operating load is realized through the sub-model method, which improves the simulation efficiency, and the calculation method of the wear amount of the main anti-wear parts of the NGW type wind power reducer is specified in detail.

[0016] Among them, the thickness of the thin film is determined by using a separate bearing model to perform a simple loading simulation. After simulation testing, it is determined that the thin film connecting the roller does not bring in excess stiffness, and the impact on the overall simulation is negligible.

[0017] Specifically, the theoretical empirical formula includes: normal contact force, contact stiffness, penetration, exponential coefficient of force, damping coefficient, and normal relative velocity of the contact point.

[0018] In summary, the finite element calculation method for the wear of the main parts of the output stage of the NGW type wind power reducer provided by the embodiment of the present invention has the following advantages: 1. Based on the previous design model, the topology optimization method Optimization module and the response surface method Parameter module can be used to optimize the structural dimensions of the main wear-resistant parts to achieve the relatively optimal state of deformation and stress, and determine the optimal numerical model for wear simulation input; 2. In the overall model simulation analysis, the designed assembly clearance and interference are considered, and the real bearing inner and outer rings and roller models are used. However, the cage between the rollers is simplified and all the rollers are connected with small thin sheets. The thickness of the thin sheet is determined by using a separate bearing model for simple loading simulation. After simulation testing, it is determined that the thin sheet connecting the rollers does not bring in excess stiffness, and the impact on the overall simulation can be ignored. 3. Using the Transient Structural module in ANSYS-Workbench software, in order to control the simulation accuracy and adjust the contact error, a high-order hexahedral grid was used. All model grids were solid186. According to Archard theory, the transient dynamics simulation method was used to solve the wear volume of the main anti-wear parts in the output stage of the NGW wind power reducer after one rotation. Nonlinear calculations were involved, and the material nonlinearity was taken into account. The corresponding anisotropic elastic material and bilinear isotropic hardening material properties were constructed using more relevant material test data. Archard theory roughly includes parameters such as sliding index, pressure index, wear coefficient, and material hardness. In order to calculate the wear amount more accurately, the contact penetration value in the friction contact was reduced to e -4 Below, the normal stiffness value in the contact setting is obtained by theoretical calculation; the theoretical empirical formula includes: normal contact force, contact stiffness, penetration, force exponential coefficient, damping coefficient, and normal relative velocity of the contact point; Fourth, by building sub-models, the simulation calculation time is reduced, the simulation efficiency is improved, and the nonlinear accumulation of the wear volume of the wear-resistant parts over the entire life is solved to obtain the corresponding total wear volume.

[0019] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A finite element calculation method for the wear of the main parts of the output stage of an NGW type wind power reducer, characterized in that: include: Based on the previous design model, the topology optimization method Optimization module and the response surface method Parameter module are used to optimize the structural dimensions of the main wear-resistant parts to achieve the relatively optimal state of deformation and stress, and determine the optimal numerical model for wear simulation input; The model is simplified to reduce the simulation calculation time while ensuring the simulation accuracy; the simplification is based on the understanding of Saint-Venant's principle, that is, the chamfers or small features that do not bear force are deleted; the model is truncated based on the principle of 10 times the stiffness or mass, and the simulation model is built using fixed supports; for the simplified finite element simulation model of the transient structural module of the NGW type gear output stage, the simplification of the bearing model is particularly important in this simulation model, and a real roller model is used, but the cage between the rollers is simplified to use small thin sheets to connect all the rollers; a real bearing physical model is used, and standard friction contact is used between the bearing rollers and the inner and outer rings to improve the simulation accuracy; this model is a simulation sub-model, which is a simulation model for calculating the wear of wear-resistant gaskets and wear-resistant baffles Since it involves nonlinear calculation, material nonlinearity is now taken into account, and the corresponding anisotropic elastic material and bilinear isotropic hardening material properties are constructed using more relevant material test data; Standard friction contact is adopted. In the overall model simulation analysis, the designed assembly clearance and interference are considered. In the connection relationship between the full model and the sub-model, the APDL command flow method is used. The Archard theory is used to build a calculation model for the startup wear amount, which includes parameters such as sliding index, pressure index, wear coefficient, and material hardness. In order to calculate the wear amount more accurately, the contact penetration value in the friction contact is reduced to e -4 Below, the normal stiffness value in the contact setting is obtained using theoretical calculations; In order to control the simulation accuracy and adjust the contact error, a high-order hexahedral mesh was used, and all model meshes used solid186; According to the actual physical model, the sun gear is loaded with torque and speed, and the outer ring gear is fixedly supported; In order to ensure the accuracy of the simulation, in the calculation of the transient structural module of the whole machine, first ensure that the structure rotates for one cycle and judge that the contact penetration value is less than e -4 Finally, debug the result after the sub-model rotates for one cycle. When the two results are basically the same, it proves that there is no problem with the sub-model. Then use the sub-model to complete the wear simulation of the entire life cycle. Secondly, use the contact tool to infer whether the force on the NGW gear is correct. Finally, use the grid independence to optimize the simulation results again, and finally calculate the total wear volume in the sub-model.

2. The finite element calculation method for the wear of the main parts of the output stage of the NGW type wind power reducer according to claim 1 is characterized in that: Determination of the thickness of the thin sheet: A simple loading simulation was performed using a separate bearing model. After simulation testing, it was determined that the thin sheet connecting the rollers did not introduce any excess stiffness, and the impact on the overall simulation was negligible.

3. The finite element calculation method for the wear of the main parts of the output stage of the NGW type wind power reducer according to claim 1 is characterized in that: The theoretical empirical formula includes: normal contact force, contact stiffness, penetration, force exponential coefficient, damping coefficient, and normal relative velocity of the contact point.

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