High-speed thrust cone modification method based on thermal elastohydrodynamic lubrication model

Abstract

The invention discloses a high-speed thrust cone modification method based on a thermal elastohydrodynamic lubrication model, and belongs to the technical field of optical mechanical transmission equipment. The method aims at solving the problem that the shape correction design of the thrust cone in a gear transmission system cannot be quantified to be standard, and consequently contact stress is concentrated. Comprising the following steps: determining a modification type and modification parameters according to geometric constraints of the thrust cone; a Latin hypercube sampling method is utilized to generate a plurality of modification parameter combination sets meeting uniform coverage in the value range of the modification parameters; according to the geometric parameters, the load, the lubricating oil basic physical property and the material thermophysical property parameters of the thrust cone, a thrust cone thermoelastohydrodynamic lubrication calculation model considering shaping is established; determining a shaping parameter combination set enabling the comprehensive performance to be maximum; and then oil film parameter verification is carried out to determine the optimal modification parameter. According to the method, the modification design of the thrust cone is changed from experience to scientization and standardization.

Description

Technical Field

[0001] This invention relates to a high-speed thrust cone shaping method based on a thermo-elastohydrodynamic lubrication model, belonging to the technical field of mechanical transmission equipment. Background Technology

[0002] In gear transmission systems operating under high-speed and heavy-load conditions, the thrust cone, as a key component, bears significant axial loads.

[0003] Existing general gear standards lack detailed design guidance for the specific component, the thrust cone, particularly in terms of the lack of systematic and scientific basis for profile modification design under high-speed conditions. This makes it difficult for traditional design methods to effectively optimize the load distribution in the contact area of ​​the thrust cone, resulting in poor lubrication and easy generation of contact stress concentration, thereby affecting the load-bearing capacity, fatigue life, and operational smoothness of the gear transmission device. Summary of the Invention

[0004] To address the problem of insufficient quantifiable standards in thrust cone profile design within gear transmission systems, which leads to contact stress concentration, this invention provides a high-speed thrust cone profile modification method based on a thermo-elasto-fluidic lubrication model.

[0005] The present invention provides a high-speed thrust cone shaping method based on a thermo-elastohydrodynamic lubrication model, comprising:

[0006] The modification type and modification parameters are determined based on the geometric constraints of the thrust cone.

[0007] The Latin hypercube sampling method is used to generate multiple sets of shaping parameter combinations that satisfy uniform coverage within the range of shaping parameter values;

[0008] Based on the geometric parameters, load, basic properties of lubricating oil, and thermal properties of the material of the thrust cone, a thermo-elasto-fluidic lubrication calculation model for the thrust cone considering the shape modification is established. The thermo-elasto-fluidic lubrication calculation model is used to calculate the oil film parameters after modification corresponding to each set of modified parameters. Then, based on the oil film parameters after modification, the comprehensive performance is calculated, and the set of modified parameters that maximizes the comprehensive performance is determined.

[0009] The oil film parameters calculated from the set of shaping parameters that maximizes overall performance are verified. If the verification passes, the set of shaping parameters that maximizes overall performance is taken as the optimal shaping parameters. Otherwise, the range of values ​​for the shaping parameters is adjusted and the calculation continues until the calculated oil film parameters can pass the verification.

[0010] According to the high-speed thrust cone shaping method based on the thermo-elasto-fluidic lubrication model of the present invention, the shaping types include single-sided drum contact surface shaping, two-end rounding shaping, and asymmetric secondary shaping;

[0011] The shaping parameter corresponding to the shaping of the single-sided drum contact surface is the shaping depth;

[0012] The shaping parameters corresponding to rounding and shaping at both ends are the shaping depth and shaping width at both ends;

[0013] The shaping parameters corresponding to asymmetric quadratic shaping are the inlet quadratic curve depth, the outlet quadratic curve depth, the inlet shaping length, and the outlet shaping length.

[0014] The high-speed thrust cone shaping method based on the thermo-elasto-fluidic lubrication model according to the present invention generates a set of multiple shaping parameter combinations that satisfy uniform coverage as follows:

[0015] The range of values ​​for the shaping parameters is normalized to obtain a normalized range, and the target number of combinations of shaping parameters is set.

[0016] The Latin hypercube sampling method is used to generate a set of target number shaping parameters that satisfy uniform coverage within the normalized range.

[0017] According to the high-speed thrust cone modification method based on the thermo-elastohydrodynamic lubrication model of the present invention, the establishment of a thermo-elastohydrodynamic lubrication calculation model of the thrust cone considering the modification includes establishing the thrust cone clearance equation, elastic deformation equation and film thickness equation.

[0018] The clearance equation of the thrust cone in the XOYZ coordinate system is:

[0019] ,

[0020] In the formula X-axis coordinates Y-axis coordinate This refers to the geometric clearance between the thrust cone and the mating surface. As an intermediate variable, The cone angle of the thrust cone. As an intermediate variable;

[0021] ,

[0022] ,

[0023] In the formula Let be the perpendicular distance from the centerline of the thrust cone to the origin O. This is the perpendicular distance from the center line of the helical gear cone surface to the origin O;

[0024] ,

[0025] ,

[0026] In the formula The diameter of the large conical surface of the thrust cone. The length of the contact busbar. The perpendicular distance between the origin O and the midpoint of the contact generatrix. The diameter of the large conical surface of the helical gear;

[0027] ,

[0028] In the formula Let be the radius of the helical gear at the midpoint of the contact generatrix. The radius of the thrust cone at the midpoint of the contact generatrix;

[0029] The elastic deformation equation of the thrust cone is:

[0030] ,

[0031] In the formula For elastic deformation, The Poisson's ratio of the material for the helical gear cone surface. The Poisson's ratio of the thrust cone surface material. The Young's modulus of the material for the helical gear cone surface. The Young's modulus of the thrust cone surface material. The integral domain of the contact region. To contact pressure, The X-axis coordinates of the elastic deformation source point are... The Y-axis coordinate of the elastic deformation source point It is the equivalent elastic modulus;

[0032] The film thickness equation is:

[0033] ,

[0034] In the formula For oil film thickness, For the central film thickness, This is the equation for the modified curve.

[0035] According to the high-speed thrust cone shaping method based on the thermo-elastohydrodynamic lubrication model of the present invention, the establishment of the thermo-elastohydrodynamic lubrication calculation model of the thrust cone considering the shaping also includes establishing the circumferential velocity equations of the two conical surfaces of the thrust cone:

[0036] ,

[0037] In the formula Let be the linear velocity of the helical gear cone surface. Let be the linear velocity of the thrust cone surface. Let be the rotational speed of the helical gear. The rotational speed of the thrust cone;

[0038] This yields the relative sliding velocity of the helical gear cone surface relative to the thrust cone surface. The equation:

[0039] .

[0040] The high-speed thrust cone shaping method based on the thermo-elastohydrodynamic lubrication model of the present invention further includes the Reynolds equation in establishing a thermo-elastohydrodynamic lubrication calculation model for the thrust cone that takes into account the shaping:

[0041] ,

[0042] In the formula For the density of lubricating oil, The viscosity of the lubricating oil. The average circumferential velocity of the thrust cone. ;

[0043] The boundary conditions for the Reynolds equations are:

[0044] ,

[0045] In the formula The X-axis inlet coordinates of the contact area. The X-axis exit coordinates of the contact area. The Y-axis inlet coordinates of the contact area. The Y-axis exit coordinates of the contact area;

[0046] Solving for contact pressure using load balance conditions and :

[0047] ,

[0048] In the formula The contact area of ​​the thrust cone. This refers to the axial force acting on the thrust cone.

[0049] According to the high-speed thrust cone shaping method based on the thermo-elastohydrodynamic lubrication model of the present invention, the establishment of a thermo-elastohydrodynamic lubrication calculation model for the thrust cone considering the shaping also includes incorporating thermal effects into the viscosity and density model to obtain the lubricating oil viscosity. and lubricating oil density The calculation formula is as follows:

[0050] ,

[0051] ,

[0052] In the formula This refers to the initial viscosity of the lubricating oil. For oil film pressure, The pressure viscosity coefficient, Viscosity-compression index For oil film temperature, This refers to the initial temperature of the lubricating oil. Viscosity-temperature coefficient, This is the initial density of the lubricating oil. It is the density-temperature coefficient.

[0053] The high-speed thrust cone shaping method based on the thermo-elastohydrodynamic lubrication model of the present invention further includes an energy equation in establishing a thermo-elastohydrodynamic lubrication calculation model for the thrust cone that takes into account the shaping:

[0054] ,

[0055] In the formula This refers to the specific heat capacity of the lubricating oil. The velocity of the lubricating oil film in the X direction. The Y-axis velocity of the lubricating oil film. The thermal conductivity of the lubricating oil. This is the Z-axis coordinate.

[0056] According to the high-speed thrust cone shaping method based on the thermo-elasto-fluidic lubrication model of the present invention, the method for calculating the comprehensive performance is as follows:

[0057] Obtain the minimum oil film thickness of the thrust cone before shaping. Maximum oil film pressure before shaping and the highest oil film temperature rise before shaping Simultaneously, a thrust cone thermo-elasto-hydrodynamic lubrication calculation model was used to obtain the minimum oil film thickness after modification. Maximum oil film pressure after shaping and the highest oil film temperature after shaping Calculate overall performance :

[0058] make , , ,but

[0059]

[0060] In the formula For thickness weighting, As pressure weight, Temperature weighting.

[0061] According to the high-speed thrust cone shaping method based on the thermo-elasto-fluidic lubrication model of the present invention, the method for verifying the oil film parameters calculated by the shaping parameter combination set that maximizes the overall performance is as follows:

[0062] For the oil film parameters after shaping: the minimum oil film thickness after shaping. Maximum oil film pressure after shaping and the highest oil film temperature after shaping :

[0063] ;

[0064] In the formula denoted as the root mean square roughness of the contact surface of the helical gear. denoted as the root mean square roughness of the thrust cone contact surface;

[0065] ,

[0066] In the formula The minimum pressure required to cause deformation of the thrust cone contact surface;

[0067] ,

[0068] In the formula The minimum temperature at which the properties of lubricating oil are significantly altered.

[0069] The beneficial effects of the present invention are as follows: The method of the present invention is used for the design and optimization of the thrust cone in high-speed heavy-duty gearboxes, which can effectively improve the performance of the thrust cone, extend its service life, and thus improve the overall reliability of the gearbox.

[0070] This invention optimizes load distribution: Scientific shaping design ensures a more uniform load distribution in the thrust cone contact area, avoiding stress concentration. It improves lubrication: By increasing the minimum oil film thickness, the lubrication condition of the thrust cone is effectively improved, reducing direct contact wear. It enhances load-bearing capacity and lifespan: Uniform load distribution and good lubrication significantly improve the load-bearing capacity and fatigue life of the thrust cone. It improves operational stability: Reduced vibration and impact ensure stable and smooth operation of the gear transmission device under harsh conditions. It provides quantitative design basis: The method of this invention provides quantitative calculation basis, enabling the thrust cone shaping design to shift from empirical to scientific and standardized. Attached Figure Description

[0071] Figure 1 This is the front view of the thrust cone;

[0072] Figure 2 This is a side view of the thrust cone;

[0073] Figure 3 A schematic diagram of the reshaping of the contact surface of a single-sided drum;

[0074] Figure 4 A schematic diagram for rounding and shaping both ends;

[0075] Figure 5 This is a schematic diagram of asymmetric secondary shaping;

[0076] Figure 6 This is a flowchart of the high-speed thrust cone shaping method based on the thermo-elastohydrodynamic lubrication model described in this invention. Detailed Implementation

[0077] 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.

[0078] Specific Implementation Method 1: Combination Figures 1 to 6 As shown, this invention provides a high-speed thrust cone shaping method based on a thermo-elastohydrodynamic lubrication model, comprising:

[0079] The type and parameters of the modification are determined based on the geometric constraints and machining capabilities of the thrust cone.

[0080] The Latin hypercube sampling method is used to generate multiple sets of shaping parameter combinations that satisfy uniform coverage within the range of shaping parameter values;

[0081] Based on the geometric parameters, load, basic properties of lubricating oil, and thermal properties of the material of the thrust cone, a thermo-elasto-fluidic lubrication calculation model for the thrust cone considering the shape modification is established. The thermo-elasto-fluidic lubrication calculation model is used to calculate the oil film parameters after modification corresponding to each set of modified parameters. Then, based on the oil film parameters after modification, the comprehensive performance is calculated, and the set of modified parameters that maximizes the comprehensive performance is determined.

[0082] The oil film parameters calculated from the set of shaping parameters that maximizes overall performance are verified. If the verification passes, the set of shaping parameters that maximizes overall performance is taken as the optimal shaping parameters. Otherwise, the range of values ​​for the shaping parameters is adjusted and the calculation continues until the calculated oil film parameters can pass the verification.

[0083] Furthermore, combined with Figures 3 to 5 As shown, the shaping types include single-sided drum contact surface shaping, rounding of both ends shaping, and asymmetrical secondary shaping;

[0084] The shaping parameter corresponding to the shaping of the single-sided drum contact surface is the shaping depth;

[0085] The shaping parameters corresponding to rounding and shaping at both ends are the shaping depth and shaping width at both ends;

[0086] The shaping parameters corresponding to asymmetric quadratic shaping are the inlet quadratic curve depth, the outlet quadratic curve depth, the inlet shaping length, and the outlet shaping length.

[0087] The equation for the shaping curve of a single-sided drum contact surface is:

[0088] ,

[0089] in For the modified equation, For shaping depth, The y-axis exit coordinates of the contact area.

[0090] The equation of the shaping curve with rounded ends:

[0091] ,

[0092] To modify the width, This is the starting point for shaping the left side of the thrust cone. This is the starting point for shaping the right side of the thrust cone.

[0093] The equation of the shaping curve for asymmetric quadratic shaping is:

[0094] ,

[0095] In the formula The depth of the reshaping on the left side. The depth of the reshaping on the right side. The width of the left side is adjusted. This refers to the width of the right-side shaping.

[0096] Based on the selected shaping type and geometric constraints, determine the value range of each shaping parameter.

[0097] The method for generating a set of multiple shaping parameter combinations that satisfy uniform coverage is as follows:

[0098] The range of values ​​for the shaping parameters is normalized to obtain a normalized range, and the target number of combinations of shaping parameters is set.

[0099] The Latin hypercube sampling method is used to generate a set of target number shaping parameters that satisfy uniform coverage within the normalized range.

[0100] Furthermore, combining Figure 1 and Figure 2 As shown, the calculation model for the thermo-elasto-fluidic lubrication of the thrust cone, which takes into account the shape modification, includes establishing the thrust cone clearance equation, elastic deformation equation, and film thickness equation.

[0101] The clearance equation of the thrust cone in the XOYZ coordinate system is:

[0102] ,

[0103] In the formula X-axis coordinates Y-axis coordinate This refers to the geometric clearance between the thrust cone and the mating surface. As an intermediate variable, The cone angle of the thrust cone. As an intermediate variable;

[0104] ,

[0105] ,

[0106] In the formula Let be the perpendicular distance from the centerline of the thrust cone to the origin O. This is the perpendicular distance from the center line of the helical gear cone surface to the origin O;

[0107] ,

[0108] ,

[0109] In the formula The diameter of the large conical surface of the thrust cone. The length of the contact busbar. The perpendicular distance between the origin O and the midpoint of the contact generatrix. The diameter of the large conical surface of the helical gear;

[0110] ,

[0111] In the formula Let be the radius of the helical gear at the midpoint of the contact generatrix. The radius of the thrust cone at the midpoint of the contact generatrix;

[0112] When two thrust cones made of different materials come into contact, the elastic deformation generated under the pressure distribution of the contact pressure is as follows:

[0113] The elastic deformation equation of the thrust cone is:

[0114] ,

[0115] In the formula For elastic deformation, The Poisson's ratio of the material for the helical gear cone surface. The Poisson's ratio of the thrust cone surface material. The Young's modulus of the material for the helical gear cone surface. The Young's modulus of the thrust cone surface material. The integral domain of the contact region. To contact pressure, The X-axis coordinates of the elastic deformation source point are... The Y-axis coordinate of the elastic deformation source point It is the equivalent elastic modulus; ;

[0116] The film thickness equation is:

[0117] ,

[0118] In the formula For oil film thickness, The thickness of the central film is denoted as , and is an undetermined constant. This is the equation for the modified curve.

[0119] Figure 1 and Figure 2 middle, Let O be the coordinate origin of the helical gear thrust cone. Let the origin of the small thrust cone be the coordinate system. The midpoint of the contact busbar; XYZ is the small thrust cone coordinate system, and xyz is the helical gear thrust cone coordinate system.

[0120] Establishing a thermo-elasto-fluidic lubrication calculation model for the thrust cone that takes into account the shape modification also includes establishing the circumferential velocity equations for the two conical surfaces of the thrust cone:

[0121] ,

[0122] In the formula Let be the linear velocity of the helical gear cone surface. Let be the linear velocity of the thrust cone surface. Let be the rotational speed of the helical gear. The rotational speed of the thrust cone;

[0123] This yields the relative sliding velocity of the helical gear cone surface relative to the thrust cone surface. The equation:

[0124] .

[0125] The calculation model for the thermo-elasto-hydrodynamic lubrication of the thrust cone, which takes into account the shape modification, also includes the Reynolds equation:

[0126] ,

[0127] In the formula For the density of lubricating oil, The viscosity of the lubricating oil. The average circumferential velocity of the thrust cone. ;

[0128] The boundary conditions for the Reynolds equations are:

[0129] ,

[0130] In the formula The X-axis inlet coordinates of the contact area. The X-axis exit coordinates of the contact area. The Y-axis inlet coordinates of the contact area. The Y-axis exit coordinates of the contact area;

[0131] Solving for contact pressure using load balance conditions and :

[0132] ,

[0133] In the formula The contact area of ​​the thrust cone. This refers to the axial force acting on the thrust cone.

[0134] Establishing a thermo-elasto-hydrodynamic lubrication calculation model for the thrust cone that takes into account the shape modification also involves incorporating thermal effects into the viscosity and density models, and using the Roelands equation and the Dowson-Higginson formula to obtain the lubricating oil viscosity. and lubricating oil density The calculation formula is as follows:

[0135] ,

[0136] ,

[0137] In the formula This refers to the initial viscosity of the lubricating oil. For oil film pressure, The pressure viscosity coefficient is taken as 1.96 × 10⁻⁶. 8 ; The viscosity-compression index has a value of 0.68. For oil film temperature, This refers to the initial temperature of the lubricating oil. This is the viscosity-temperature coefficient, with a value of -1.1; This is the initial density of the lubricating oil. This is the density-temperature coefficient, with a value of -0.00035℃. -1 .

[0138] The calculation model for the thermo-elasto-hydrodynamic lubrication of the thrust cone, which takes into account the shape modification, also includes the energy equation:

[0139] ,

[0140] In the formula This refers to the specific heat capacity of the lubricating oil. The velocity of the lubricating oil film in the X direction. The Y-axis velocity of the lubricating oil film. The thermal conductivity of the lubricating oil. This is the Z-axis coordinate.

[0141] Finally, the method for calculating the overall performance is as follows:

[0142] First, without considering the shaping parameters, obtain the minimum oil film thickness of the thrust cone before shaping. Maximum oil film pressure before shaping and the highest oil film temperature rise before shaping Simultaneously, a thrust cone thermo-elasto-hydrodynamic lubrication calculation model was used to obtain the minimum oil film thickness after modification. Maximum oil film pressure after shaping and the highest oil film temperature after shaping Calculate overall performance :

[0143] make , , ,but

[0144]

[0145] In the formula For thickness weighting, a value of 0.5 can be used; As the pressure weight, it can be taken as 0.3; The temperature weight can be set to 0.2.

[0146] The method for verifying the oil film parameters calculated from the set of shaping parameters that maximizes overall performance is as follows:

[0147] For the oil film parameters after shaping: the minimum oil film thickness after shaping. Maximum oil film pressure after shaping and the highest oil film temperature after shaping :

[0148] To avoid contact wear and extend fatigue life, the minimum oil film thickness should always be greater than three times the sum of the roughnesses.

[0149] ;

[0150] In the formula denoted as the root mean square roughness of the contact surface of the helical gear. denoted as the root mean square roughness of the thrust cone contact surface;

[0151] and The value can be measured on the actual thrust cone surface using a professional surface roughness measuring instrument. If direct measurement is not possible, it can be estimated and referenced based on the roughness requirements on the design drawings, the processing technology used, or relevant industry standards.

[0152] ,

[0153] In the formula The minimum pressure required to cause deformation of the thrust cone contact surface;

[0154] Oil film pressure Below the contact stress threshold; the shaping parameters should effectively reduce or disperse the maximum oil film pressure, keeping it below the allowable contact stress of the material, and avoiding excessive pressure concentration as much as possible. As the shaping depth increases, the maximum oil film pressure may show a linear increasing trend, and the maximum oil film pressure should not exceed the limit pressure that would lead to contact fatigue or plastic deformation.

[0155] ,

[0156] In the formula The minimum temperature at which the properties of lubricating oil are significantly altered.

[0157] Oil film temperature Within the temperature threshold range. The modification parameters should control the maximum oil film temperature rise within the allowable temperature range to avoid lubricant deterioration and component thermal deformation. Generally, it should be ensured that the maximum operating temperature of the lubricant does not exceed its thermal oxidation stability limit.

[0158] Example: Using the parameters shown in Table 1 as the working conditions, the asymmetric secondary shaping method is selected.

[0159] surface Operating parameters and geometric parameters

[0160]

[0161] Select the corresponding formula as the modified curve equation to obtain the modified film thickness equation. The film thickness equation and formula are the calculation formulas corresponding to the thrust cone thermo-elasto-fluid lubrication calculation model that takes into account the modification, and together they form the lubrication mathematical model.

[0162] Table 2. Range of shaping parameters

[0163]

[0164] Using Latin hypercube sampling, 1000 parameter combinations were selected from the range of shaping parameters in Table 2. Each parameter combination was substituted into the thrust cone thermo-elastohydrodynamic lubrication calculation model to calculate the minimum oil film thickness, maximum oil film pressure, and maximum oil film temperature rise. The comprehensive performance was calculated based on the oil film parameters, and the parameter combination with the largest comprehensive performance was found. In this embodiment, when the left side shaping width ratio is 32.4%, the left side shaping depth is 3.35 μm, the right side shaping width ratio is 48.4%, and the right side shaping depth is 12.758 μm, the minimum oil film thickness is 51.19 μm, the maximum oil film pressure is 20.375 MPa, and the maximum oil film temperature rise is 2.924 °C, the comprehensive performance is the largest, with a value of 1.057.

[0165] Verification:

[0166] Under the current operating conditions, Both μm and 51.19μm satisfy the requirements. The safety margin requirement is met to effectively avoid contact wear. The thrust cone material, 40Cr steel, has an allowable surface fatigue stress of 1300-1600 MPa and a maximum oil film pressure of 20.375 MPa, which meets the requirements.

[0167] Maximum oil film temperature rise:

[0168] Under current operating conditions, the initial temperature of the lubricating oil is 45℃. The trend of the maximum oil film temperature rise is basically consistent with the maximum oil film pressure, and it also increases linearly with the increase of the cutting depth. To avoid lubricating oil deterioration and component thermal deformation, the temperature rise needs to be controlled below 40℃. The maximum oil film temperature rise of 2.924℃ is within an acceptable range.

[0169] In summary, the optimal shaping parameters for this embodiment are: a left-side shaping width of 32.4%, a left-side shaping depth of 3.35 μm, a right-side shaping width of 48.4%, and a right-side shaping depth of 12.758 μm.

[0170] While the invention has been described herein with reference to specific embodiments, it should be understood that these embodiments are merely examples of the principles and applications of the invention. Therefore, it should be understood that many modifications can be made to the exemplary embodiments, and other arrangements can be designed without departing from the spirit and scope of the invention as defined by the appended claims. It should be understood that different dependent claims and features described herein can be combined in ways different from those described in the original claims. It is also understood that features described in conjunction with individual embodiments can be used in other described embodiments.

Claims

1. A method of high speed thrust cone profile modification based on thermoelastohydrodynamic lubrication model, characterized in that The method comprises the following steps: determine the modification type and modification parameters according to the geometric constraints of the thrust cone; generate a plurality of modification parameter combination sets that satisfy uniform coverage in the value range of the modification parameters by using a Latin hypercube sampling method; establish a thermal elastohydrodynamic lubrication calculation model of the thrust cone considering modification according to the geometric parameters, load, basic properties of lubricating oil, and material thermal physical parameters of the thrust cone; calculate the oil film parameters corresponding to each modification parameter combination set by using the thermal elastohydrodynamic lubrication calculation model of the thrust cone, and then calculate the comprehensive performance based on the modified oil film parameters to determine the modification parameter combination set that maximizes the comprehensive performance; verify the oil film parameters calculated by the modification parameter combination set that maximizes the comprehensive performance, and if the verification is passed, the modification parameter combination set that maximizes the comprehensive performance is taken as the optimal modification parameter, otherwise, the value range of the modification parameters is adjusted for continuous calculation until the calculated oil film parameters can pass the verification.

2. The high-speed thrust cone modification method based on a thermal elastohydrodynamic lubrication model according to claim 1, wherein the modification type comprises single-sided drum contact surface modification, two-end round modification, and asymmetric quadratic modification; the modification parameter corresponding to the single-sided drum contact surface modification is a modification depth; the modification parameters corresponding to the two-end round modification are two-end modification depths and two-end modification widths; the modification parameters corresponding to the asymmetric quadratic modification are an inlet-end quadratic curve depth, an outlet-end quadratic curve depth, an inlet-end modification length, and an outlet-end modification length.

3. The high-speed thrust cone modification method based on a thermal elastohydrodynamic lubrication model according to claim 2, wherein the method for generating a plurality of modification parameter combination sets that satisfy uniform coverage is as follows: normalize the value range of the modification parameters to obtain a normalized value range, and set a target number of modification parameter combination sets; generate the target number of modification parameter combination sets that satisfy uniform coverage in the normalized value range by using a Latin hypercube sampling method.

4. The high-speed thrust cone modification method based on a thermal elastohydrodynamic lubrication model according to claim 3, wherein establishing the thermal elastohydrodynamic lubrication calculation model of the thrust cone considering modification comprises establishing a thrust cone gap equation, an elastic deformation equation, and a film thickness equation; ， wherein is the X axis coordinate, is the Y axis coordinate, is the geometric clearance between the thrust cone and the mating surface, is an intermediate variable, is the cone angle of the thrust cone, is an intermediate variable; ， ， wherein is the perpendicular distance from the axis of the thrust cone to the origin O, is the perpendicular distance from the axis of the helical gear cone to the origin O; ， ， wherein is the diameter of the large bevel of the thrust cone, is the length of the contact generatrix, is the perpendicular distance from the coordinate origin O to the midpoint of the contact generatrix, is the diameter of the large bevel of the helical gear; ， wherein R is the radius of the bevel gear at the midpoint of the line of contact, R is the radius of the thrust cone at the midpoint of the line of contact; the gap equation of the thrust cone in an XOYZ coordinate system is as follows: ， wherein is the Poisson's ratio of the helical gear cone material, is the Poisson's ratio of the thrust cone cone material, is the Young's modulus of the helical gear cone material, is the Young's modulus of the thrust cone cone material, is the Young's modulus of the helical gear cone material, is the integral domain of the contact area, is the contact pressure, is the X-axis coordinate of the source point of the elastic deformation, is the Y-axis coordinate of the source point of the elastic deformation, is the equivalent elastic modulus; the elastic deformation equation of the thrust cone is as follows: ， wherein is the oil film thickness, is the center film thickness, is the profile curve equation. the film thickness equation is as follows:

5. The high-speed thrust cone modification method based on a thermal elastohydrodynamic lubrication model according to claim 4, wherein ， wherein is the linear velocity of the helical gear cone, is the linear velocity of the thrust cone cone, is the rotational speed of the helical gear, is the rotational speed of the thrust cone; The relative sliding velocity of the bevel gear cone surface with respect to the thrust cone cone surface is then obtained Equation: 。 establishing the thermal elastohydrodynamic lubrication calculation model of the thrust cone considering modification further comprises establishing a circumferential velocity equation of the two cone surfaces of the thrust cone:

6. The high-speed thrust cone modification method based on a thermal elastohydrodynamic lubrication model according to claim 5, wherein ， wherein is the lubricating oil density, is the lubricating oil viscosity, is the thrust cone mean peripheral velocity, ; establishing the thermal elastohydrodynamic lubrication calculation model of the thrust cone considering modification further comprises a Reynolds equation: ， wherein Xin is an X-in coordinate of the contact area, Xout is an X-out coordinate of the contact area, Yin is a Y-in coordinate of the contact area, Yout is a Y-out coordinate of the contact area; Solving contact pressure with load balance condition with : ， wherein is the contact area of the thrust cone, is the axial force on the thrust cone. the boundary conditions of the Reynolds equation are as follows: The establishment of the thermal elastohydrodynamic lubrication calculation model of the thrust cone considering the modification also includes introducing the thermal effect into the viscosity and density model to obtain the calculation formula of the lubricating oil viscosity and the lubricating oil density ​ ， ， wherein is the initial viscosity of the lubricating oil, is the oil film pressure, is the pressure viscosity coefficient, is the viscosity-pressure exponent, is the oil film temperature, is the initial temperature of the lubricating oil, is the viscosity-temperature coefficient, is the initial density of the lubricating oil, is the density-temperature coefficient.

7. The high-speed thrust cone modification method based on a thermal elastohydrodynamic lubrication model according to claim 6, wherein 8. The high-speed thrust cone modification method based on a thermal elastohydrodynamic lubrication model according to claim 7, wherein establishing the thermal elastohydrodynamic lubrication calculation model of the thrust cone considering modification further comprises an energy equation: ， wherein Cp is the specific heat capacity of the lubricating oil, Vx is the X-direction velocity of the lubricating oil film, Vy is the Y-direction velocity of the lubricating oil film, k is the thermal conductivity of the lubricating oil, Z is the Z-axis coordinate.

9. The method of claim 8, wherein the method of calculating the comprehensive performance is:

10. The method of claim 9, wherein the method of calculating the comprehensive performance is: Obtaining minimum oil film thickness before modification of thrust cone , maximum oil film pressure before modification and maximum oil film temperature rise before modification ; At the same time, the minimum oil film thickness of the modified thrust cone is obtained by using the thermal elastohydrodynamic lubrication calculation model , the maximum oil film pressure of the modified thrust cone , and the highest oil film temperature of the modified thrust cone , and the comprehensive performance is calculated : making , , then In the formula is the thickness weight, is the pressure weight, is the temperature weight.

11. The method of claim 9, wherein the method of verifying the oil film parameters calculated for the set of modification parameter combinations that maximize the comprehensive performance is: ​ for the shaped oil film parameters: minimum oil film thickness after shaping maximum oil film pressure after shaping and maximum oil film temperature after shaping : ； wherein Rpk is the root mean square roughness of the helical gear contact surface, Rpk is the root mean square roughness of the helical gear contact surface, ， In the formula Minimum pressure for deforming the thrust cone contact surface ， In the formula The minimum temperature at which the properties of the lubricating oil are significantly changed.

Images