Single-arm planet carrier spline finite element analysis method based on submodel technology

Abstract

The invention discloses a single-arm planet carrier spline finite element analysis method based on a sub-model technology, relates to the technical field of mechanical structure strength analysis, is used for solving the technical problem that efficiency and precision of a traditional finite element analysis method are difficult to consider at the same time, and can effectively reduce calculation resource consumption while ensuring the stress calculation precision of a planet carrier spline. The single-arm planet carrier spline finite element analysis method based on the sub-model technology comprises the following steps of global model establishment, global model solution, sub-model establishment, sub-model network optimization and iterative convergence verification. According to the finite element analysis method for the spline of the single-arm planet carrier based on the sub-model technology, efficient and high-precision analysis of stress at the spline of the planet carrier is achieved through a hierarchical calculation strategy of'global model-sub-model 'in combination with dynamic boundary condition mapping and local grid optimization.

Description

Technical Field

[0001] The present invention relates to the technical field of mechanical structure strength analysis, and in particular to a finite element analysis method for a single-arm planetary carrier spline based on sub-model technology, which is particularly suitable for local refined stress analysis of key connection parts in a planetary gear transmission system. Background Art

[0002] Currently, planetary carriers, as the load-bearing framework of planetary gear systems, need to withstand the combined effects of dynamic meshing loads, centrifugal force, and gravity from the planetary gears. Single-arm planetary carriers, due to their asymmetric support structure, can reduce axial space usage by 15% to 30% compared to double-arm carriers, making them more adaptable to the trend of compact design. Specifically, the spline connection of a single-arm planetary carrier is prone to stress concentration due to the transmission of large torque and alternating loads, leading to fatigue failure. The inventors of this application have discovered that conventional finite element analysis in the prior art has the following main deficiencies: (1) Insufficient accuracy of the global model: To improve computational efficiency, the global model mesh is coarse, making it difficult to accurately capture the stress concentration phenomenon at the spline tooth root (the error can reach 20% to 30%). (2) Waste of computing resources: If the global model is directly refined in the spline area, the model will be too large (the number of nodes will increase by 5 to 10 times) and the computing time will be significantly extended.

[0003] Therefore, how to provide a finite element analysis method for the spline of a single-arm planetary carrier based on sub-model technology, which can effectively reduce the consumption of computing resources while ensuring the stress calculation accuracy at the planetary carrier spline, has become a technical problem that technical personnel in this field urgently need to solve. Summary of the Invention

[0004] The purpose of the present invention is to provide a finite element analysis method for a single-arm planet carrier spline based on sub-model technology, which is used to solve the technical problem that it is difficult to strike a balance between efficiency and accuracy in traditional finite element analysis methods.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions: A finite element analysis method for a single-arm planet carrier spline based on a sub-modeling technique includes the following steps: Global model establishment: Use UG software to establish a finite element model of the planetary carrier and import it into Workbench, define material properties, use a coarse mesh to divide the global model, and add loads and boundary conditions; Global model solution: Perform preliminary calculations to obtain the global stress distribution and identify stress concentration areas at the spline; Establish a sub-model: take the stress concentration area of ​​the spline as the center and intercept the sub-model area containing local geometric features; Sub-model network optimization: Adaptive mesh refinement is performed on the sub-model area, with a focus on densifying the spline tooth roots and contact surface areas prone to failure; Iterative convergence verification: Compare the deformation consistency of the sub-model and the global model, and perform convergence verification on the stress at the spline of the sub-model.

[0006] In practical applications, the finite element model is a global model; The material properties include: material is 42CrMoA, density is 7850kg / m 3 , Young's model is 212GPa, Poisson's ratio is 0.28; The load and boundary conditions are added to add bearing loads to the planetary shaft and fix the actual working surface of the spline.

[0007] The sub-model is established by using a "dynamic interpolation method" to extract the displacement field of the sub-model boundary nodes from the global model results and use it as the boundary condition of the sub-model to avoid errors caused by traditional rigid constraints.

[0008] Specifically, the deformation consistency between the compared sub-model and the global model is: if the relative error is greater than 2%, the interpolation algorithm is adjusted and recalculated; The convergence verification of the stress at the spline of the sub-model is as follows: if the relative error is greater than 5%, the interpolation algorithm is adjusted and recalculated.

[0009] Compared with the existing technology, the finite element analysis method for the single-arm planet carrier spline based on the sub-model technology described in the present invention has the following advantages: In the finite element analysis method for the splines of a single-arm planetary carrier based on sub-model technology provided by the present invention, a finite element model of the planetary carrier is established by using UG software and imported into Workbench, material properties are defined, a coarser grid is used to divide the global model, and loads and boundary conditions are added; preliminary calculations are performed to obtain the global stress distribution and identify the stress concentration area at the spline; a sub-model area containing local geometric features is intercepted with the spline stress concentration area as the center; the sub-model area is adaptively refined with a focus on encrypting the spline tooth root and the contact surface failure-prone area; the deformation consistency of the sub-model and the global model is compared, and the stress at the spline of the sub-model is converged and verified; therefore, the finite element analysis method for the splines of a single-arm planetary carrier based on sub-model technology provided by the present invention realizes efficient and high-precision analysis of stress at the splines of the planetary carrier through a hierarchical calculation strategy of "global model → sub-model" combined with dynamic boundary condition mapping and local grid optimization. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 A schematic structural diagram of a global model in a finite element analysis method for a single-arm planet carrier spline based on sub-model technology provided in an embodiment of the present invention; Figure 2 A schematic structural diagram of a sub-model in a finite element analysis method for a single-arm planet carrier spline based on sub-model technology provided in an embodiment of the present invention.

[0011] Reference numerals: 1-Spline part. DETAILED DESCRIPTION

[0012] For ease of understanding, the finite element analysis method for the spline of a single-arm planet carrier based on the sub-model technology provided by an embodiment of the present invention is described in detail below in conjunction with the accompanying drawings.

[0013] The embodiment of the present invention provides a finite element analysis method for a single-arm planet carrier spline based on sub-model technology, such as Figure 1 and Figure 2 As shown, the following steps are included: Global model establishment: Use UG software to establish a finite element model of the planetary carrier and import it into Workbench, define material properties, use a coarse mesh to divide the global model, and add loads and boundary conditions; Global model solution: Perform preliminary calculations to obtain the global stress distribution and identify stress concentration areas at the spline; Establish a sub-model: take the stress concentration area of ​​the spline as the center and intercept the sub-model area containing local geometric features; Sub-model network optimization: Adaptive mesh refinement is performed on the sub-model area, with a focus on densifying the spline tooth roots and contact surface areas prone to failure; Iterative convergence verification: Compare the deformation consistency of the sub-model and the global model, and perform convergence verification on the stress at the spline of the sub-model.

[0014] Compared with the prior art, the finite element analysis method for the single-arm planet carrier spline based on the sub-model technology described in the embodiment of the present invention has the following advantages: In the finite element analysis method for the splines of a single-arm planetary carrier based on sub-model technology provided in an embodiment of the present invention, a finite element model of the planetary carrier is established by using UG software and imported into Workbench, material properties are defined, a coarser grid is used to divide the global model, and loads and boundary conditions are added; preliminary calculations are performed to obtain the global stress distribution and identify the stress concentration area at the spline; a sub-model area containing local geometric features is intercepted with the spline stress concentration area as the center; the sub-model area is adaptively refined with a focus on encrypting the spline tooth root and the contact surface prone to failure area; the deformation consistency of the sub-model and the global model is compared, and the stress at the spline of the sub-model is converged and verified; therefore, the finite element analysis method for the splines of a single-arm planetary carrier based on sub-model technology provided in an embodiment of the present invention, through the hierarchical calculation strategy of "global model → sub-model", combined with dynamic boundary condition mapping and local grid optimization, realizes efficient and high-precision analysis of stress at the splines of the planetary carrier.

[0015] In practical applications, the above finite element model is also a global model; The above material properties may include: material is 42CrMoA, density is 7850kg / m 3 , Young's model is 212GPa, Poisson's ratio is 0.28; The above loads and boundary conditions are added to add bearing loads at the planetary shaft and fix the actual working surface of the spline.

[0016] Among them, the above-mentioned sub-model establishment can use the "dynamic interpolation method" to extract the displacement field of the sub-model boundary nodes from the global model results and use it as the boundary condition of the sub-model to avoid the errors caused by traditional rigid constraints.

[0017] Specifically, the deformation consistency between the above-mentioned comparison sub-model and the global model can be: if the relative error is greater than 2%, the interpolation algorithm is adjusted and recalculated; The above convergence verification of the stress at the spline of the sub-model can be: if the relative error is greater than 5%, the interpolation algorithm is adjusted and recalculated.

[0018] In summary, the finite element analysis method for the single-arm planet carrier spline based on the sub-modeling technology provided in the embodiment of the present invention has the following advantages: 1. Improved computational efficiency: The number of global model grids is reduced by 70% to 80%, and the sub-model calculation time is only 1 / 5 of that of traditional methods; 2. Significantly improved accuracy: The maximum stress error at the tooth root is reduced from 25% to less than 3%.

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

Claims

1. A finite element analysis method for a single-arm planet carrier spline based on sub-modeling technology, characterized in that: The following steps are involved: Global Model establishment: Use UG software to establish the planet carrier finite element model and import it into Workbench, define material properties, use a coarse grid to divide the global model, and add loads and boundary conditions; Global model solution: Perform preliminary calculations to obtain the global stress distribution and identify stress concentration areas at the spline; Establish a sub-model: take the stress concentration area of ​​the spline as the center and intercept the sub-model area containing local geometric features; Sub-model network optimization: Adaptive mesh refinement is performed on the sub-model area, with a focus on densifying the spline tooth roots and contact surface areas prone to failure; Iterative convergence verification: Compare the deformation consistency of the sub-model and the global model, and perform convergence verification on the stress at the spline of the sub-model.

2. The finite element analysis method for the spline of a single-arm planet carrier based on sub-modeling technology according to claim 1 is characterized in that: The finite element model is a global model; The material properties include: material is 42CrMoA, density is 7850kg / m 3 , Young's model is 212GPa, Poisson's ratio is 0.28; The load and boundary conditions are added to add bearing loads to the planetary shaft and fix the actual working surface of the spline.

3. The finite element analysis method for the spline of a single-arm planet carrier based on sub-modeling technology according to claim 1 is characterized in that: The sub-model is established by using a "dynamic interpolation method" to extract the displacement field of the sub-model boundary nodes from the global model results and use it as the boundary condition of the sub-model to avoid errors caused by traditional rigid constraints.

4. The finite element analysis method for the spline of a single-arm planet carrier based on sub-modeling technology according to claim 1 is characterized in that: The deformation consistency between the compared sub-model and the global model is: if the relative error is greater than 2%, the interpolation algorithm is adjusted and recalculated; The convergence verification of the stress at the spline of the sub-model is as follows: if the relative error is greater than 5%, the interpolation algorithm is adjusted and recalculated.

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