Method and system for predicting distribution of lubricating oil in lean oil state of surface-textured bearing

Abstract

The invention discloses a surface texturing bearing lean oil state lubricating oil distribution prediction method and system, and relates to the field of cylindrical roller bearing surface texturing, and the method comprises the steps: extracting a fluid domain from 1 / n of a simplified geometric model; the fluid domain is subjected to unstructured grid division and then imported into FLUENT software, a lubricating oil density cloud picture and a speed vector diagram in a lean oil state are obtained through the software, and then the oil flow density and the speed distribution condition of an inner raceway contact area of the cylindrical roller bearing containing the surface texture are obtained; and utilizing finite element software to perform fluid-solid coupling on the fluid domain subjected to unstructured mesh division and 1 / n of the simplified geometric model to obtain the oil film thickness of the surface texture, and further obtaining the oil film thickness distribution condition of the surface texture. According to the method, the oil flow density distribution and speed distribution condition of the inner raceway contact area of the cylindrical roller bearing containing the surface texture can be predicted, and the oil film thickness distribution condition of the surface texture can be predicted.

Description

Technical Field

[0001] This invention relates to the field of cylindrical roller bearing surface texture technology, and in particular to a method and system for predicting lubricant distribution in a surface-textured bearing under lean-oil conditions. Background Technology

[0002] Rolling bearings are widely used in critical machinery and equipment in national defense, transportation, energy, and logistics. Cylindrical roller bearings, as fundamental and key components, operate under complex environments such as high speed and high temperature for extended periods, requiring stringent lubrication conditions. If a cylindrical roller bearing fails due to lubrication issues, the entire machine will shut down, potentially leading to accidents or even significant economic losses.

[0003] Surface texture is a microstructure with specific dimensions, shapes, and arrangements created on the surface of a material using specialized processing methods, thereby reducing friction and wear. The recessed structure of the surface texture can be considered a miniature oil reservoir. When the bearing is in operation, the recessed texture can provide a small amount of lubricating oil to the contact area, facilitating the generation of hydrodynamic pressure on the contact surface, thus enhancing the lubrication performance and surface load-bearing capacity of the friction pair. Simultaneously, the recessed texture can also collect some of the tiny abrasive particles generated during bearing operation, thereby reducing wear on the contact surface caused by abrasive scratches.

[0004] For cylindrical roller bearings with surface texture (including those with surface texture) operating under lean oil conditions, in order to verify the positive effect of surface texture on the lubrication performance of cylindrical roller bearings, further research is needed on the lubrication and damping performance of surface texture. This requires knowing the oil flow density and velocity distribution in the inner raceway contact area of ​​cylindrical roller bearings with surface texture, as well as the oil film thickness distribution of the surface texture. However, currently there is no method to predict the oil flow density and velocity distribution in the inner raceway contact area of ​​cylindrical roller bearings with surface texture, or to predict the oil film thickness distribution of the surface texture. Summary of the Invention

[0005] The purpose of this invention is to provide a method and system for predicting the lubricating oil distribution in a lean state of a surface-textured bearing. This method can predict the oil flow density distribution and velocity distribution in the inner raceway contact area of ​​a cylindrical roller bearing with surface texture, and also predict the oil film thickness distribution of the surface texture.

[0006] To achieve the above objectives, the present invention provides the following solution:

[0007] A method for predicting lubricant distribution in a bearing under lean-oil condition with surface texturing, the method comprising:

[0008] A geometric model of a surface-textured cylindrical roller bearing is constructed; the geometric model includes an inner raceway, an outer raceway, and cylindrical rollers; wherein the surface of the inner raceway is surface-textured.

[0009] The geometric model is simplified to obtain a simplified geometric model;

[0010] Choose 1 / n of the simplified geometric model; n is a positive integer greater than 1;

[0011] Extract the fluid domain from 1 / n of the simplified geometric model;

[0012] After the fluid domain is divided into an unstructured mesh, it is imported into FLUENT software. The FLUENT software is used to obtain the lubricating oil density cloud map and the lubricating oil velocity vector map under the lean oil condition.

[0013] The oil flow density distribution in the inner raceway contact area of ​​the cylindrical roller bearing with surface texture is obtained from the lubricating oil density cloud map, and the oil flow velocity distribution in the inner raceway contact area of ​​the cylindrical roller bearing with surface texture is obtained from the lubricating oil velocity vector map.

[0014] After the fluid domain is meshed into an unstructured mesh, it is imported into the finite element software. At the same time, 1 / n of the simplified geometric model is imported into the finite element software. The finite element software is used to perform fluid-structure interaction between the fluid domain after meshing into an unstructured mesh and 1 / n of the simplified geometric model to obtain the oil film thickness of the surface texture.

[0015] The oil film thickness distribution of the surface texture is obtained based on the oil film thickness of the surface texture.

[0016] Optionally, the geometric model for constructing the surface-textured cylindrical roller bearing specifically includes:

[0017] A geometric model of a surface-textured cylindrical roller bearing was constructed using 3D modeling software.

[0018] Optionally, after unstructured mesh generation of the fluid domain, the data is imported into FLUENT software. The FLUENT software is then used to obtain the lubricating oil density cloud map and lubricating oil velocity vector map under lean oil conditions, specifically including:

[0019] After unstructured mesh generation using ICEM software, the fluid domain is imported into FLUENT software. The fluid domain is set as a moving region, and the rotational speed of the fluid domain is set to the revolution speed of the cylindrical rollers in the surface-textured cylindrical roller bearing. The rotational center of the fluid domain is the center of the surface-textured cylindrical roller bearing. The cylindrical rollers are stationary relative to the fluid domain. The outer surface of the fluid domain of the surface-textured cylindrical roller bearing is given as a stationary wall, and the inner raceway of the surface-textured cylindrical roller bearing is given as the rotational speed of the shaft. The FLUENT software is used to obtain the lubricating oil density cloud map and the lubricating oil velocity vector map under lean oil conditions.

[0020] Optionally, the revolution speed of the cylindrical roller is determined using formula n. c =n i (1-γ) / 2 is calculated; where n is... i n is the inner raceway rotational speed of the surface-textured cylindrical roller bearing. c Let γ be the revolution speed of the cylindrical roller, and γ be an intermediate geometric parameter of the bearing, γ = Dcosα / d m d m Let D be the pitch circle diameter of the cylindrical roller, D be the diameter of the cylindrical roller, and α be the contact angle between the cylindrical roller and the inner raceway. The contact angle α of the surface-textured cylindrical roller bearing is 0.

[0021] The present invention also provides the following solutions:

[0022] A surface-textured bearing lubricant distribution prediction system under lean-oil conditions, the system comprising:

[0023] A geometric model construction module is used to construct a geometric model of a surface-textured cylindrical roller bearing; the geometric model includes an inner raceway, an outer raceway, and cylindrical rollers; wherein the surface of the inner raceway is surface-textured.

[0024] A geometric model simplification module is used to simplify the geometric model to obtain a simplified geometric model;

[0025] The 1 / n geometric model selection module is used to select 1 / n of the simplified geometric model; n is a positive integer greater than 1.

[0026] The fluid domain extraction module is used to extract 1 / n of the fluid domain from the simplified geometric model.

[0027] The density cloud map and velocity vector map generation module is used to perform unstructured mesh generation on the fluid domain and then import it into FLUENT software. The FLUENT software is used to obtain the lubricating oil density cloud map and lubricating oil velocity vector map under lean oil conditions.

[0028] The module for obtaining oil flow density and velocity distribution is used to obtain the oil flow density distribution in the inner raceway contact area of ​​the cylindrical roller bearing with surface texture based on the lubricating oil density cloud map, and to obtain the oil flow velocity distribution in the inner raceway contact area of ​​the cylindrical roller bearing with surface texture based on the lubricating oil velocity vector map.

[0029] The fluid-structure interaction module is used to perform unstructured mesh generation on the fluid domain and import it into the finite element software. At the same time, it imports 1 / n of the simplified geometric model into the finite element software. The finite element software is used to perform fluid-structure interaction on the fluid domain after unstructured mesh generation and 1 / n of the simplified geometric model to obtain the oil film thickness of the surface texture.

[0030] The oil film thickness distribution module is used to obtain the oil film thickness distribution of the surface texture based on the oil film thickness of the surface texture.

[0031] Optionally, the geometric model construction module specifically includes:

[0032] The geometric model building unit is used to construct the geometric model of a surface-textured cylindrical roller bearing using 3D modeling software.

[0033] Optionally, the module for obtaining the density cloud map and velocity vector map specifically includes:

[0034] Density cloud map and velocity vector map are obtained as elements, which are used to perform unstructured mesh generation of the fluid domain using ICEM software and then import the mesh into FLUENT software. The fluid domain is set as a moving region, and the rotational speed of the fluid domain is set as the revolution speed of the cylindrical rollers in the surface-textured cylindrical roller bearing. The rotational center of the fluid domain is the center of the surface-textured cylindrical roller bearing. The cylindrical rollers are stationary relative to the fluid domain. The outer surface of the fluid domain of the surface-textured cylindrical roller bearing is given as a stationary wall, and the inner raceway of the surface-textured cylindrical roller bearing is given as the rotational speed of the shaft. The FLUENT software is used to obtain the lubricating oil density cloud map and lubricating oil velocity vector map under lean oil conditions.

[0035] Optionally, the revolution speed of the cylindrical roller is determined using formula n. c =n i (1-γ) / 2 is calculated; where n is... i n is the inner raceway rotational speed of the surface-textured cylindrical roller bearing. c Let γ be the revolution speed of the cylindrical roller, and γ be an intermediate geometric parameter of the bearing, γ = Dcosα / d m d mLet D be the pitch circle diameter of the cylindrical roller, D be the diameter of the cylindrical roller, and α be the contact angle between the cylindrical roller and the inner raceway. The contact angle α of the surface-textured cylindrical roller bearing is 0.

[0036] According to specific embodiments provided by the present invention, the present invention discloses the following technical effects:

[0037] This invention discloses a method and system for predicting lubricating oil distribution in a lean-oil state of a surface-textured bearing. The method involves constructing a geometric model of a surface-textured cylindrical roller bearing, extracting a fluid domain from the simplified geometric model (1 / n), and then meshing the fluid domain using an unstructured mesh. The fluid domain is then imported into FLUENT software, where a lubricating oil density cloud map and a lubricating oil velocity vector map are obtained under lean-oil conditions. Based on these data, the oil flow density and velocity distribution in the inner raceway contact area of ​​the surface-textured cylindrical roller bearing are predicted. Furthermore, by using finite element method (FEM) software to perform fluid-structure interaction between the unstructured meshed fluid domain and the simplified geometric model (1 / n), the oil film thickness of the surface texture is obtained. Finally, the oil film thickness distribution of the surface texture is predicted based on this oil film thickness. Attached Figure Description

[0038] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0039] Figure 1 This is a flowchart of a method for predicting lubricating oil distribution in a bearing under lean-oil conditions using surface texturing, according to the present invention.

[0040] Figure 2 This is a schematic diagram of a cylindrical roller bearing model with surface texture in this invention;

[0041] Figure 3 This is a simplified model diagram of a 1 / 12 scale cylindrical roller bearing with surface texture in this invention.

[0042] Figure 4 A simplified model of a 1 / 12 surface-textured cylindrical roller bearing in this invention includes a fluid domain.

[0043] Figure 5 This is a schematic diagram of the raceway texture distribution in a simplified model of a 1 / 12 surface-textured cylindrical roller bearing used in this invention.

[0044] Figure 6 This is a schematic diagram of the cylindrical texture in this invention;

[0045] Figure 7 This is a schematic diagram of fluid domain mesh division under lean oil conditions in this invention;

[0046] Figure 8 This is a density cloud diagram of the lubricating oil under lean oil conditions in this invention;

[0047] Figure 9 This is a vector diagram of the lubricating oil velocity under lean oil conditions in this invention. Detailed Implementation

[0048] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0049] The purpose of this invention is to provide a method and system for predicting the lubricating oil distribution in a lean state of a surface-textured bearing. This method can predict the oil flow density distribution and velocity distribution in the inner raceway contact area of ​​a cylindrical roller bearing with surface texture, and also predict the oil film thickness distribution of the surface texture.

[0050] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0051] Figure 1 This is a flowchart of a method for predicting lubricant distribution in a bearing under lean-oil conditions using surface texturing, according to the present invention. Figure 1 As shown, the present invention provides a method for predicting lubricant distribution in a surface-textured bearing under lean-oil conditions, comprising the following steps:

[0052] Step 101: Construct the geometric model of the surface-textured cylindrical roller bearing; the geometric model includes the inner raceway, the outer raceway, and the cylindrical rollers; wherein, the surface of the inner raceway is surface-textured.

[0053] Step 101 specifically includes:

[0054] A geometric model of a surface-textured cylindrical roller bearing (including a geometric model of a surface-textured cylindrical roller bearing) is constructed using 3D modeling software. The model includes the inner raceway, outer raceway, and cylindrical rollers. The inner raceway surface of the cylindrical roller bearing is textured, i.e., the inner raceway surface is textured.

[0055] The surface texture is a cylindrical texture. Several surface textures are set on the inner raceway surface of the cylindrical roller bearing. The surface textures are arranged in a circumferential and linear array. Specifically, several surface textures are arranged in a circumferential and linear array on the inner raceway of the cylindrical roller bearing. The composition parameters of the surface texture include radial depth, texture diameter, circumferential angle, and the number of axial textures on the bearing surface.

[0056] Step 102: Simplify the geometric model to obtain the simplified geometric model.

[0057] The geometric model is simplified by ignoring the factors of the cylindrical roller bearing cage and fillet, resulting in a simplified geometric model. Figure 2 The surface-textured cylindrical roller bearing model in this invention is a simplified model of the surface-textured cylindrical roller bearing obtained by simplifying the geometric model of the surface-textured cylindrical roller bearing and ignoring the cage and fillet factors of the cylindrical roller bearing.

[0058] Step 103: Select 1 / n of the simplified geometric model; n is a positive integer greater than 1.

[0059] Due to the periodicity of the bearing structure's rotation, a 1 / n model of the bearing can be selected for mesh generation and calculation, thereby reducing the computational load on the computer. Figure 3 This is a simplified model diagram of a 1 / 12 scale cylindrical roller bearing with surface texture in this invention. Figure 3 In the diagram, 1 represents the outer raceway, 2 represents the rolling element (i.e., cylindrical roller), 3 represents the inner raceway, and 4 represents the inner raceway texture, which is the surface texture set on the inner raceway surface.

[0060] Step 104: Extract the fluid domain from the 1 / n of the simplified geometric model.

[0061] Extracting the fluid domain is equivalent to constructing a fluid domain model, which is essentially a surface lubrication model of the surface texture. Constructing the surface lubrication model involves extracting the bearing fluid domain under lean-oil conditions (the fluid domain along the inner raceway surface under lean-oil conditions). Under lean-oil conditions, the distribution of lubricating oil around the rolling contact is determined by the two-phase flow of lubricating oil and air.

[0062] When constructing the surface lubrication model with surface texture, the structural parameters, material parameters, operating conditions, and lubrication parameters of the bearing are obtained. A geometric model of the cylindrical roller bearing with surface texture is established using the 3D modeling software SOLIDWORKS. The geometric model of the cylindrical roller bearing is simplified to establish a simplified fluid domain model. Due to the rotational periodicity of the bearing structure, a 1 / 12 model of the bearing (taking 1 / 12 of the entire bearing and extracting the fluid domain from this 1 / 12 portion) can be selected for mesh generation and calculation (simulation calculation). A fluid domain with a height of 0.1 mm along the inner ring of the bearing is extracted; that is, a fluid domain with a height of 0.1 mm along the inner ring of the bearing is extracted from 1 / 12 of the fluid domain model. Figure 4 This is a simplified model diagram of a 1 / 12 surface-textured cylindrical roller bearing in this invention, including a fluid domain. Figure 4 5 represents the fluid domain. The fluid domain (i.e., the fluid domain with a height of 0.1 mm along the inner ring of the bearing) is meshed using ICEM without structure. The two end faces of the bearing along the rotation direction are set as rotational periodic meshes. The two end faces of the fluid domain in both directions are set as rotational periodic surfaces with a rotation angle of 30°. Local refinement processing is performed on the textured region to ensure calculation accuracy.

[0063] Step 105: After generating an unstructured mesh for the fluid domain, import it into FLUENT software and use FLUENT software to obtain the lubricating oil density cloud map and lubricating oil velocity vector map under lean oil conditions.

[0064] Step 105 specifically includes:

[0065] After unstructured mesh generation of the fluid domain using ICEM software, the mesh was imported into FLUENT software. The fluid domain was set as a moving region, and the rotational speed of the fluid domain was set to the revolution speed of the cylindrical rollers in the surface-textured cylindrical roller bearing. The rotational center of the fluid domain was the center of the surface-textured cylindrical roller bearing. The cylindrical rollers were stationary relative to the fluid domain. The outer surface of the fluid domain of the surface-textured cylindrical roller bearing was given as a stationary wall, and the inner raceway of the surface-textured cylindrical roller bearing was given as the rotational speed of the shaft. The lubricating oil density cloud map and lubricating oil velocity vector map under lean oil conditions were obtained using FLUENT software.

[0066] The revolution speed of the cylindrical roller is calculated using the formula n. c =n i (1-γ) / 2 is calculated; where n is... i n represents the internal raceway speed of a surface-textured cylindrical roller bearing. c Let γ be the orbital speed of the cylindrical roller, and γ be an intermediate geometric parameter of the bearing, γ = Dcosα / d m d mLet be the pitch circle diameter of the cylindrical roller, D be the diameter of the cylindrical roller, and α be the contact angle between the cylindrical roller and the inner raceway. The contact angle α = 0 for surface-textured cylindrical roller bearings.

[0067] Step 106: Obtain the oil flow density distribution in the inner raceway contact area of ​​the cylindrical roller bearing with surface texture based on the lubricating oil density cloud map, and obtain the oil flow velocity distribution in the inner raceway contact area of ​​the cylindrical roller bearing with surface texture based on the lubricating oil velocity vector map.

[0068] The oil density cloud map directly shows the oil flow density distribution in the inner raceway contact area of ​​a cylindrical roller bearing with surface texture, while the oil velocity vector map directly shows the oil flow velocity distribution in the inner raceway contact area of ​​a cylindrical roller bearing with surface texture.

[0069] Step 107: After generating an unstructured mesh for the fluid domain, import it into the finite element software. At the same time, import the simplified geometric model 1 / n into the finite element software. Use the finite element software to perform fluid-structure interaction on the fluid domain after generating the unstructured mesh and the simplified geometric model 1 / n to obtain the oil film thickness of the surface texture.

[0070] The oil film thickness of the surface texture is the thickness of the lubricating oil stored in the surface texture.

[0071] Step 108: Obtain the oil film thickness distribution of the surface texture based on the oil film thickness of the surface texture.

[0072] Figure 5 This is a schematic diagram of the raceway texture distribution in a simplified model of a 1 / 12 surface-textured cylindrical roller bearing used in this invention. Figure 6 This is a schematic diagram of the cylindrical texture in this invention. Figure 6 The number 4 indicates the inner raceway texture. Since there are multiple surface textures, after obtaining the oil film thickness of each surface texture, the oil film thickness distribution of the surface texture can be obtained based on the oil film thickness of each surface texture.

[0073] Figure 7 This is a schematic diagram of fluid domain mesh division under lean oil conditions in this invention. Figure 7 In Figure 5, the fluid domain is represented. By meshing the fluid domain and setting it to a periodic grid, the distribution of lubricating oil thickness (oil film thickness distribution) of the surface texture is calculated and analyzed. After the surface texture is calculated by the surface lubrication model, the oil flow density distribution and velocity distribution in the inner raceway contact area of ​​the cylindrical roller bearing containing the surface texture can be obtained by analyzing the contour plot. Figure 8 This is a density cloud diagram of the lubricating oil under lean oil conditions in this invention. Figure 9 This is a vector diagram of the lubricating oil velocity under lean oil conditions in this invention, with the inner raceway of the cylindrical roller bearing serving as the bearing surface. Figure 8In the text, contour represents the outline, density represents the density, (phase-1) is a face that is set for observation, and contour-5Density(phase-1) is a randomly generated name with no special meaning. Figure 9 In the vector, vector represents a vector, velocityMagnitude represents the velocity magnitude, and vector-1velocityMagnitude(mi...) represents a velocity vector contour map.

[0074] After unstructured meshing of the fluid domain, the data is imported into the finite element method (FEM) software. Simultaneously, the simplified geometric model's 1 / n, the oil distribution field calculation formula, and the oil volume fraction calculation formula are also imported into the FEM software. The FEM software is then used to perform fluid-structure interaction (FSI) between the unstructured meshed fluid domain and the simplified geometric model's 1 / n. Based on the built-in functions of the FEM software, the oil film thickness of the surface texture, i.e., the lubricating oil distribution, can be obtained. This is achieved by using the oil distribution field formula... Formula for volume fraction of oil in, Input the volume fraction formula into the finite element software. Substituting into the oil distribution field formula By combining the mass and momentum conservation equations built into the finite element method (FEM) software, the oil film thickness of the surface texture can be obtained from the simulation results, thereby analyzing the oil distribution and film thickness distribution. Here, 'a' represents the phase content, and '·' represents the gradient operator. Applied to aU.

[0075] Oil distribution field middle, This means taking the partial derivative with respect to a. Let be the symbol for the gradient operator, U be the velocity field (oil distribution is determined by the velocity field), U is unknown, and U is obtained according to the mass conservation equation; the volume fraction of oil. middle, V represents the volume fraction of oil in the i-th grid. i Let C be the volume of oil in the i-th grid. i Let H(x,t) be the field function for the region of the i-th grid, ρ(x,t) be the density at a point, x be the coordinate, t be the time, and ρ be the density at a point. air ρ represents air density. oil The density of the oil is represented; it is discretized using the finite volume method.

[0076] The lubricating oil in cylindrical roller bearings is mixed using an oil-gas two-phase flow model, and the VOF model is used in multiphase flow models. The volume fraction of the oil is calculated using the VOF model.

[0077] The technical solution of the present invention is illustrated below with a specific embodiment:

[0078] The bearing parameters in this embodiment are shown in Table 1. The surface texture is a cylindrical texture, and several surface textures are arranged in a circumferential and linear array. The composition parameters of the surface texture include radial depth, texture diameter, circumferential angle, and the number of axial textures on the bearing surface. In this embodiment, the radial depth of the surface texture is 0.05 mm, the texture diameter is 0.06 mm, the number of axial textures is 6 or 10, the circumferential angle is 10°, and the rotational speed of the inner raceway is 3000 r / min.

[0079] Table 1 Bearing Parameters

[0080] parameter numerical values Bearing outer diameter / mm 52 bearing inner diameter / mm 25 Number of rollers 12 Roller diameter / mm 7.5 Bearing width / mm 15 Inner raceway diameter / mm 31.4 Outer raceway diameter / mm 46.4 Lubricating oil viscosity / Pa·s 0.0733 <![CDATA[Lubricating oil density / kg·m 3 > 822 Environmental pressure / Pa 101325 Elastic modulus / Pa <![CDATA[2.25×10 11 ]]> Surface tension coefficient / N·m 0.028

[0081] The method for predicting lubricant distribution in a surface-textured bearing under lean-oil conditions in this embodiment includes the following steps:

[0082] Step 1: Use 3D modeling software to construct the geometric model of the cylindrical roller bearing with surface texture, including the inner raceway, outer raceway, and cylindrical rollers, wherein the inner raceway surface of the cylindrical roller bearing is textured.

[0083] Step 2: Construct a surface lubrication model of surface texture, extract the bearing fluid domain under lean oil conditions, and the oil distribution around the rolling contact under lean oil conditions is determined by the two-phase flow of oil and air.

[0084] Step 3: Mesh the fluid domain and set it as a periodic grid. Calculate and analyze the oil film distribution of the surface texture. After the surface texture is calculated by the surface lubrication model, the oil flow density distribution and velocity distribution of the cylindrical roller bearing contact area (inner raceway contact area of ​​the bearing) containing the surface texture can be obtained by analyzing the cloud map. The inner raceway of the cylindrical roller bearing is the bearing surface.

[0085] This embodiment obtains the oil flow distribution of a cylindrical roller bearing with surface texture through the above calculations, verifying the positive effect of surface texture on the lubrication performance of cylindrical roller bearings.

[0086] In this embodiment, when constructing the surface lubrication model with surface texture, the structural parameters, material parameters, operating conditions, and lubrication parameters of the bearing are obtained. The geometric model of the cylindrical roller bearing with surface texture is established using the 3D modeling software SOLIDWORKS. The geometric model of the cylindrical roller bearing is simplified by ignoring the factors of the cylindrical roller bearing cage and fillets, and a simplified fluid domain model is established. Due to the rotational periodicity of the bearing structure, a 1 / 12 model of the bearing is selected for mesh generation and calculation. A fluid domain with a height of 0.1 mm along the inner ring of the bearing is extracted. The fluid domain is meshed using ICEM without structure. The two end faces of the bearing along the rotation direction are set as rotational periodic meshes, and the two circumferential end faces of the fluid domain are set as rotational periodic surfaces with a rotation angle of 30°. Local densification processing is performed on the textured area to ensure calculation accuracy.

[0087] In this embodiment, the fluid domain is meshed using the ICEM preprocessing module and then imported into the Fluent analysis module. The fluid domain is set as a moving region, and its rotational speed is set to the revolution speed of the rollers in the cylindrical roller bearing. The center of rotation of the fluid domain is the center of the cylindrical roller bearing. The rollers are stationary relative to the fluid domain. The outer surface of the fluid domain of the cylindrical roller bearing is given as a stationary wall, and the inner raceway of the cylindrical roller bearing is given as the rotational speed of the shaft. The revolution speed of the rollers is calculated by the following formula:

[0088] n c =n i (1-γ) / 2

[0089] γ=Dcosα / d m

[0090] Where, n i n is the rotational speed of the inner raceway of the cylindrical roller bearing. c Let d be the orbital speed of the roller. m Let D be the pitch circle diameter of the roller, D be the diameter of the roller, and α be the contact angle between the roller and the inner raceway. For cylindrical roller bearings, the contact angle α = 0.

[0091] The oil distribution field is as follows:

[0092]

[0093] The volume fraction of oil is:

[0094]

[0095] in:

[0096]

[0097] Discretization is performed using the finite volume method.

[0098] In this embodiment, the lubricating oil in the cylindrical roller bearing adopts an oil-gas two-phase flow mixing model and uses the VOF model in the multiphase flow model.

[0099] This invention relates to cylindrical roller bearings with surface texture. For cylindrical roller bearings with surface texture operating under lean oil conditions, a two-phase flow CFD model is proposed to address the relationship between lean oil conditions and lubricating oil film thickness distribution. This model can calculate the oil / flow field near the textured inner raceway surface under lean oil conditions and predict the lubricating oil film thickness along the textured inner raceway. This invention verifies the positive effect of surface texture on the lubrication performance of cylindrical roller bearings by calculating the oil flow distribution (in the case of oil flow distribution) of cylindrical roller bearings with surface texture.

[0100] Based on the method for predicting lubricant distribution in a lean-oil state of a surface-textured bearing provided by this invention, this invention also provides a system for predicting lubricant distribution in a lean-oil state of a surface-textured bearing, the system comprising the following modules:

[0101] The geometry model building module is used to build the geometry model of the surface-textured cylindrical roller bearing; the geometry model includes the inner raceway, the outer raceway, and the cylindrical rollers; wherein the surface of the inner raceway is textured.

[0102] The geometric model simplification module is used to simplify the geometric model to obtain a simplified geometric model.

[0103] The 1 / n geometric model selection module is used to select 1 / n of the simplified geometric model; n is a positive integer greater than 1.

[0104] The fluid domain extraction module is used to extract the fluid domain from the simplified geometric model at a ratio of 1 / n.

[0105] The module for obtaining density cloud maps and velocity vector maps is used to import the unstructured mesh of the fluid domain into FLUENT software, and then use FLUENT software to obtain the lubricating oil density cloud map and lubricating oil velocity vector map under lean oil conditions.

[0106] The module for obtaining oil flow density and velocity distribution is used to obtain the oil flow density distribution in the inner raceway contact area of ​​a cylindrical roller bearing with surface texture based on the lubricating oil density cloud map, and to obtain the oil flow velocity distribution in the inner raceway contact area of ​​a cylindrical roller bearing with surface texture based on the lubricating oil velocity vector map.

[0107] The fluid-structure interaction module is used to import the unstructured mesh of the fluid domain into the finite element software, and at the same time import the simplified geometric model 1 / n into the finite element software. The finite element software is then used to perform fluid-structure interaction between the unstructured mesh of the fluid domain and the simplified geometric model 1 / n to obtain the oil film thickness of the surface texture.

[0108] The oil film thickness distribution module is used to obtain the oil film thickness distribution of the surface texture based on the oil film thickness of the surface texture.

[0109] Specifically, the geometric model construction module includes:

[0110] The geometric model building unit is used to construct the geometric model of a surface-textured cylindrical roller bearing using 3D modeling software.

[0111] The module for obtaining density cloud maps and velocity vector maps specifically includes:

[0112] Density cloud map and velocity vector map are used to obtain elements for unstructured mesh generation of the fluid domain using ICEM software and then imported into FLUENT software. The fluid domain is set as a moving region, and the rotational speed of the fluid domain is set to the revolution speed of the cylindrical rollers in the surface-textured cylindrical roller bearing. The rotational center of the fluid domain is the center of the surface-textured cylindrical roller bearing. The cylindrical rollers are stationary relative to the fluid domain. The outer surface of the fluid domain of the surface-textured cylindrical roller bearing is given as a stationary wall, and the inner raceway of the surface-textured cylindrical roller bearing is given as the rotational speed of the shaft. The density cloud map and velocity vector map of the lubricating oil under lean oil conditions are obtained using FLUENT software.

[0113] The revolution speed of the cylindrical roller is calculated using the formula n. c =n i (1-γ) / 2 is calculated; where n is... i n represents the internal raceway speed of a surface-textured cylindrical roller bearing. c Let γ be the orbital speed of the cylindrical roller, and γ be an intermediate geometric parameter of the bearing, γ = Dcosα / d m d m Let be the pitch circle diameter of the cylindrical roller, D be the diameter of the cylindrical roller, and α be the contact angle between the cylindrical roller and the inner raceway. The contact angle α = 0 for surface-textured cylindrical roller bearings.

[0114] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the systems disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the descriptions are relatively simple; relevant parts can be referred to the method section.

[0115] This document uses specific examples to illustrate the principles and implementation methods of the present invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of the present invention. Furthermore, those skilled in the art will recognize that, based on the ideas of the present invention, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of the present invention.

Claims

1. A method for predicting lubricant distribution in a surface-textured bearing under lean-oil conditions, characterized in that, The method includes: A geometric model of a surface-textured cylindrical roller bearing is constructed; the geometric model includes an inner raceway, an outer raceway, and cylindrical rollers; wherein the surface of the inner raceway is surface-textured. The geometric model is simplified to obtain a simplified geometric model; Choose 1 / n of the simplified geometric model; n is a positive integer greater than 1; Extract the fluid domain from 1 / n of the simplified geometric model; After the fluid domain is divided into an unstructured mesh, it is imported into FLUENT software. The FLUENT software is used to obtain the lubricating oil density cloud map and the lubricating oil velocity vector map under the lean oil condition. The oil flow density distribution in the inner raceway contact area of ​​the cylindrical roller bearing with surface texture is obtained from the lubricating oil density cloud map, and the oil flow velocity distribution in the inner raceway contact area of ​​the cylindrical roller bearing with surface texture is obtained from the lubricating oil velocity vector map. After the fluid domain is meshed into an unstructured mesh, it is imported into the finite element software. At the same time, 1 / n of the simplified geometric model is imported into the finite element software. The finite element software is used to perform fluid-structure interaction between the fluid domain after meshing into an unstructured mesh and 1 / n of the simplified geometric model to obtain the oil film thickness of the surface texture. The oil film thickness distribution of the surface texture is obtained based on the oil film thickness of the surface texture.

2. The method for predicting lubricating oil distribution in a lean-oil state of a bearing with surface texturing according to claim 1, characterized in that, The geometric model for constructing the surface-textured cylindrical roller bearing specifically includes: A geometric model of a surface-textured cylindrical roller bearing was constructed using 3D modeling software.

3. The method for predicting lubricating oil distribution in a lean-oil state of a bearing with surface textured bearings according to claim 1, characterized in that, After generating an unstructured mesh of the fluid domain, the data is imported into FLUENT software. The FLUENT software is then used to obtain the lubricating oil density cloud map and lubricating oil velocity vector map under lean oil conditions, specifically including: After unstructured mesh generation using ICEM software, the fluid domain is imported into FLUENT software. The fluid domain is set as a moving region, and the rotational speed of the fluid domain is set to the revolution speed of the cylindrical rollers in the surface-textured cylindrical roller bearing. The rotational center of the fluid domain is the center of the surface-textured cylindrical roller bearing. The cylindrical rollers are stationary relative to the fluid domain. The outer surface of the fluid domain of the surface-textured cylindrical roller bearing is given as a stationary wall, and the inner raceway of the surface-textured cylindrical roller bearing is given as the rotational speed of the shaft. The FLUENT software is used to obtain the lubricating oil density cloud map and the lubricating oil velocity vector map under lean oil conditions.

4. The method for predicting lubricating oil distribution in a lean-oil state of a surface-textured bearing according to claim 3, characterized in that, The revolution speed of the cylindrical roller is calculated using formula n. c =n i (1-γ) / 2 is calculated; where n is... i n is the inner raceway rotational speed of the surface-textured cylindrical roller bearing. c Let γ be the revolution speed of the cylindrical roller, and γ be an intermediate geometric parameter of the bearing, γ = Dcosα / d m d m Let D be the pitch circle diameter of the cylindrical roller, D be the diameter of the cylindrical roller, and α be the contact angle between the cylindrical roller and the inner raceway. The contact angle α of the surface-textured cylindrical roller bearing is 0.

5. A surface-textured bearing lubricant distribution prediction system under lean-oil conditions, characterized in that, The system includes: A geometric model construction module is used to construct a geometric model of a surface-textured cylindrical roller bearing; the geometric model includes an inner raceway, an outer raceway, and cylindrical rollers; wherein the surface of the inner raceway is surface-textured. A geometric model simplification module is used to simplify the geometric model to obtain a simplified geometric model; The 1 / n geometric model selection module is used to select 1 / n of the simplified geometric model; n is a positive integer greater than 1. The fluid domain extraction module is used to extract 1 / n of the fluid domain from the simplified geometric model. The density cloud map and velocity vector map generation module is used to perform unstructured mesh generation on the fluid domain and then import it into FLUENT software. The FLUENT software is used to obtain the lubricating oil density cloud map and lubricating oil velocity vector map under lean oil conditions. The module for obtaining oil flow density and velocity distribution is used to obtain the oil flow density distribution in the inner raceway contact area of ​​the cylindrical roller bearing with surface texture based on the lubricating oil density cloud map, and to obtain the oil flow velocity distribution in the inner raceway contact area of ​​the cylindrical roller bearing with surface texture based on the lubricating oil velocity vector map. The fluid-structure interaction module is used to perform unstructured mesh generation on the fluid domain and import it into the finite element software. At the same time, it imports 1 / n of the simplified geometric model into the finite element software. The finite element software is used to perform fluid-structure interaction on the fluid domain after unstructured mesh generation and 1 / n of the simplified geometric model to obtain the oil film thickness of the surface texture. The oil film thickness distribution module is used to obtain the oil film thickness distribution of the surface texture based on the oil film thickness of the surface texture.

6. The surface-textured bearing lubricant distribution prediction system for lean oil conditions according to claim 5, characterized in that, The geometric model construction module specifically includes: The geometric model building unit is used to construct the geometric model of a surface-textured cylindrical roller bearing using 3D modeling software.

7. The surface-textured bearing lubricant distribution prediction system for lean oil conditions according to claim 5, characterized in that, The module for obtaining the density cloud map and velocity vector map specifically includes: Density cloud map and velocity vector map are obtained as elements, which are used to perform unstructured mesh generation of the fluid domain using ICEM software and then import the mesh into FLUENT software. The fluid domain is set as a moving region, and the rotational speed of the fluid domain is set as the revolution speed of the cylindrical rollers in the surface-textured cylindrical roller bearing. The rotational center of the fluid domain is the center of the surface-textured cylindrical roller bearing. The cylindrical rollers are stationary relative to the fluid domain. The outer surface of the fluid domain of the surface-textured cylindrical roller bearing is given as a stationary wall, and the inner raceway of the surface-textured cylindrical roller bearing is given as the rotational speed of the shaft. The FLUENT software is used to obtain the lubricating oil density cloud map and lubricating oil velocity vector map under lean oil conditions.

8. The surface-textured bearing lubricant distribution prediction system for lean oil conditions according to claim 7, characterized in that, The revolution speed of the cylindrical roller is calculated using formula n. c =n i (1-γ) / 2 is calculated; where n is... i n is the inner raceway rotational speed of the surface-textured cylindrical roller bearing. c Let γ be the revolution speed of the cylindrical roller, and γ be an intermediate geometric parameter of the bearing, γ = Dcosα / d m d m Let D be the pitch circle diameter of the cylindrical roller, D be the diameter of the cylindrical roller, and α be the contact angle between the cylindrical roller and the inner raceway. The contact angle α of the surface-textured cylindrical roller bearing is 0.

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