Wheel fatigue life analysis method based on transient contact fatigue simulation technology

Abstract

The invention provides a wheel fatigue life analysis method based on a transient contact fatigue simulation technology. The method comprises the following steps: step 1, setting a wheel finite element model; 2, building a rigid-flexible coupling dynamics simulation model by adopting a transient contact fatigue simulation technology; 3, non-linear contact between the tire model and the rotating hub table is set in the simulation model, and the continuous load borne by the wheel is simulated so as to improve the simulation precision; and step 4, outputting a fatigue life cloud picture of the rim according to the transient stress result of the wheel rotating for one circle and the input fatigue stress life curve parameter of the rim material so as to analyze the fatigue life of the vehicle. According to the method, the problem that the fatigue life calculation result is inaccurate due to the fact that peak stress in the wheel rotating process is omitted and the influence of the tire pressure is not considered in the prior art is solved.

Description

Technical Field

[0001] The present application relates to the field of vehicle technology, and in particular to a wheel fatigue life analysis method based on transient contact fatigue simulation technology. Background Art

[0002] The existing wheel fatigue simulation adopts the quasi-static analysis method (quasi-static analysis, that is, describing the response of an object under approximately static conditions, that is, under conditions of very small acceleration, which ignores inertia, damping and frequency and other influencing factors). The continuous load during the actual rotation of the wheel is divided into several static loads and applied to the outer surface of the rim, which will cause the peak stress of the rim during the actual continuous rotation process to be filtered out, and ultimately make the wheel life calculated by fatigue simulation longer. In the existing technical solutions, such as CN202310147225.9 and CN201911330846.0, there are problems such as small applicability, only applicable to wheel fatigue life testing, and the strain signal collected at the strain gauge pasting position is not necessarily the maximum stress of the wheel structure, resulting in deviations in the calculated fatigue life. Summary of the invention

[0003] Based on the shortcomings of the above-mentioned wheel fatigue simulation scheme, the present invention provides a wheel fatigue life analysis method based on transient contact fatigue simulation technology. The transient nonlinear contact fatigue simulation technology is used to simulate the continuous load on the wheel, avoiding the problem that the prior art misses the peak stress during the wheel rotation process and does not consider the influence of tire pressure, resulting in inaccurate fatigue life calculation results.

[0004] The present invention provides a wheel fatigue life analysis method based on transient contact fatigue simulation technology, the method comprising: step 1, setting a wheel finite element model; step 2, using transient contact fatigue simulation technology to build a rigid-flexible coupling dynamics simulation model; step 3, setting nonlinear contact between a tire model and a hub table in the simulation model to simulate the continuous load on the wheel to improve the simulation accuracy; step 4, outputting a fatigue life cloud map of the rim according to the transient stress result of one rotation of the wheel and the input fatigue stress life curve parameters of the rim material to analyze the fatigue life of the vehicle.

[0005] Furthermore, the step 1 includes: step 11, setting the basic size of the tire and rim finite element model to L, using the hexahedral unit type; step 12, setting the tire and rim contact surface area to a contact pair connection; step 13, setting the tire internal pressure P, adjusting the elastic modulus of the tire material, so that the radial stiffness of the wheel is consistent with the design value. According to claim 2, a wheel fatigue life analysis method based on transient contact fatigue simulation technology is characterized in that the basic size of the finite element model is L=5mm.

[0006] Furthermore, the tire internal pressure P=2.5 bar.

[0007] Furthermore, the step 2 includes: step 21, establishing a hub platform model; step 22, importing a tire and rim assembly finite element model; step 23, generating a wheel assembly flexible body file and establishing a wheel flexible body model.

[0008] Furthermore, the nonlinear contact between the tire model and the hub stage is set, including: step 31, setting the outer surface of the flexible tire model as a contact surface as Setpatch1; step 32, setting the outer surface of the rigid hub stage as a contact surface as FaceSurface1; step 33, setting the above two contact surfaces that are in contact relationship as a pair of contact surfaces.

[0009] Furthermore, the simulation of the continuous load on the wheel includes: step 34, applying a radial load perpendicular to the ground downward to the wheel center to drive the hub to rotate; step 35, driving the wheel to rotate under the action of the radial load and the friction between the tire and the hub, simulating the continuous load on the wheel to avoid missing the peak stress during the wheel rotation process.

[0010] Furthermore, the step 4 includes: step 41, driving the hub to rotate the wheel, and obtaining the transient stress result of the wheel vertically downward under the radial load; step 42, selecting the transient stress result of the wheel rotating one circle, inputting the fatigue stress life curve of the rim material, and simulating and calculating the fatigue life cloud map of the rim; step 43, outputting the rim fatigue life cloud map to analyze the fatigue life of the vehicle.

[0011] Furthermore, the rim fatigue life is greater than 500,000 cycles.

[0012] The present invention provides a wheel fatigue life analysis method based on transient contact fatigue simulation technology, which is mainly used to solve the technical problems existing in the prior art, such as missing the peak stress in the wheel rotation process and not considering the influence of tire pressure. The technical solution adopts transient nonlinear contact fatigue simulation technology, builds a rigid-flexible coupling dynamic model in multi-body dynamics software, sets up nonlinear contact between the tire model and the rotating drum in the simulation model, and simulates the force of the tire pressure on the rim, thereby ensuring the consistency of the simulation and the actual bench test, improving the simulation accuracy and the efficiency of building the simulation model, and saving the wheel fatigue life analysis cycle. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a schematic flow chart of a wheel fatigue life analysis method based on transient contact fatigue simulation technology provided by the present invention; Figure 2 is a schematic diagram of a finite element model of a tire and a rim provided by the present invention; Figure 3 It is a schematic diagram of the tire and rim fitting area provided by the present invention; Figure 4 is a schematic diagram of setting the internal tire pressure of a tire provided by the present invention; Figure 5 It is a schematic diagram of importing the finite element model of the tire and rim assembly provided by the present invention into multi-body dynamics software; Figure 6 It is a schematic diagram of setting a pair of contact surfaces provided by the present invention; Figure 7 is a schematic diagram of a continuous load on a simulated wheel provided by the present invention; Figure 8 It is a schematic diagram of transient stress results of the wheel provided by the present invention under the radial load vertically downward from the ground; Fig. 9 It is a schematic diagram of the fatigue SN curve of the rim material provided by the present invention; Fig.10 It is a schematic diagram of the rim fatigue life cloud diagram provided by the present invention. DETAILED DESCRIPTION

[0014] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0015] Embodiment 1: The present invention provides a wheel fatigue life analysis method based on transient contact fatigue simulation technology, such as Figure 1 As shown, the method includes: Step 1, setting the wheel finite element model; Step 2, using transient contact fatigue simulation technology to build a rigid-flexible coupling dynamics simulation model; Step 3, setting nonlinear contact between the tire model and the hub in the simulation model to simulate the continuous load on the wheel to improve the simulation accuracy; Step 4: Output the fatigue life cloud diagram of the rim according to the transient stress result of one rotation of the wheel and the input fatigue stress life curve parameters of the rim material to analyze the fatigue life of the vehicle.

[0016] The present invention provides a wheel fatigue life analysis method based on transient contact fatigue simulation technology, which is mainly used to solve the technical problems existing in the prior art, such as missing the peak stress in the wheel rotation process and not considering the influence of tire pressure. The technical solution adopts transient nonlinear contact fatigue simulation technology, builds a rigid-flexible coupling dynamic model in multi-body dynamics software, sets up nonlinear contact between the tire model and the rotating drum in the simulation model, and simulates the force of the tire pressure on the rim, thereby ensuring the consistency of the simulation and the actual bench test, improving the simulation accuracy and the efficiency of building the simulation model, and saving the wheel fatigue life analysis cycle.

[0017] Embodiment 2: The present invention provides a wheel fatigue life analysis method based on transient contact fatigue simulation technology, such as Figure 1 As shown, the method includes: Step 1, setting the wheel finite element model; like Figure 2 , Figure 3 , Figure 4 As shown, step 1 includes the following steps.

[0018] Step 11, setting the basic size of the tire and rim finite element model to L, and using the hexahedral unit type; Step 12, setting the tire and rim fitting surface areas to be in contact connection; Step 13, setting the tire internal pressure P and adjusting the elastic modulus of the tire material so that the radial stiffness of the wheel is consistent with the design value.

[0019] The tire internal pressure P=2.5 bar, and the basic size of the finite element model is L=5 mm.

[0020] Step 2, using transient contact fatigue simulation technology to build a rigid-flexible coupling dynamics simulation model; Step 3, setting nonlinear contact between the tire model and the hub in the simulation model to simulate the continuous load on the wheel to improve the simulation accuracy; Step 4: Output the fatigue life cloud diagram of the rim according to the transient stress result of one rotation of the wheel and the input fatigue stress life curve parameters of the rim material to analyze the fatigue life of the vehicle.

[0021] The present invention provides a wheel fatigue life analysis method based on transient contact fatigue simulation technology, which is mainly used to solve the technical problems existing in the prior art, such as missing the peak stress in the wheel rotation process and not considering the influence of tire pressure. The technical solution adopts transient nonlinear contact fatigue simulation technology, builds a rigid-flexible coupling dynamic model in multi-body dynamics software, sets up nonlinear contact between the tire model and the rotating drum in the simulation model, and simulates the force of the tire pressure on the rim, thereby ensuring the consistency of the simulation and the actual bench test, improving the simulation accuracy and the efficiency of building the simulation model, and saving the wheel fatigue life analysis cycle.

[0022] Embodiment three: The present invention provides a wheel fatigue life analysis method based on transient contact fatigue simulation technology, such as Figure 1 As shown, the method includes: Step 1, setting the wheel finite element model; Step 2, using transient contact fatigue simulation technology to build a rigid-flexible coupling dynamics simulation model; like Figure 5 , Figure 6 , Figure 7 As shown, the step 2 comprises the following steps. Step 21, establishing a hub table model; Step 22, importing the tire and rim assembly finite element model; Step 23, generating a wheel assembly flexible body file and establishing a wheel flexible body model.

[0023] The transient contact fatigue simulation technology refers to fatigue simulation using transient dynamics analysis and nonlinear contact. Transient dynamics analysis is a method for analyzing the dynamic response of a structure whose load changes over time. The displacement, strain and stress of the structure that change over time are output. Inertia force and damping are very important in transient dynamics. If the inertia force and damping can be ignored, quasi-static analysis can be used instead of transient dynamics analysis. The area size and mutual position of the contact interface and the contact state of nonlinear contact are not only unknown in advance, but also change over time.

[0024] Step 3, setting nonlinear contact between the tire model and the hub in the simulation model to simulate the continuous load on the wheel to improve the simulation accuracy; like Figure 8 As shown, since the software for simulating and calculating the fatigue life of the wheel in this application is a comprehensive software that integrates multi-body dynamics simulation and fatigue simulation, the fatigue simulation module of the software can directly calculate the fatigue life of the rim based on the transient stress results of one rotation of the wheel and the fatigue SN curve parameters of the input rim material. The step 3 includes the following steps.

[0025] Step 31, setting the outer surface of the flexible tire model as a contact surface as Setpatch1; Step 32, setting the outer surface of the rigid body hub as the contact surface as FaceSurface1; Step 33: setting the above two contact surfaces in contact relationship as a pair of contact surfaces.

[0026] Step 34, applying a radial load perpendicular to the ground and downward to the wheel center to drive the hub to rotate; Step 35, driving the wheel to rotate under the action of radial load and friction between the tire and the hub, simulating the continuous load on the wheel to avoid missing the peak stress during the wheel rotation process.

[0027] Step 4: Output the fatigue life cloud diagram of the rim according to the transient stress result of one rotation of the wheel and the input fatigue stress life curve parameters of the rim material to analyze the fatigue life of the vehicle.

[0028] The present invention provides a wheel fatigue life analysis method based on transient contact fatigue simulation technology, which is mainly used to solve the technical problems existing in the prior art, such as missing the peak stress in the wheel rotation process and not considering the influence of tire pressure. The technical solution adopts transient nonlinear contact fatigue simulation technology, builds a rigid-flexible coupling dynamic model in multi-body dynamics software, sets up nonlinear contact between the tire model and the rotating drum in the simulation model, and simulates the force of the tire pressure on the rim, thereby ensuring the consistency of the simulation and the actual bench test, improving the simulation accuracy and the efficiency of building the simulation model, and saving the wheel fatigue life analysis cycle.

[0029] Embodiment 4: The present invention provides a wheel fatigue life analysis method based on transient contact fatigue simulation technology, such as Figure 1 As shown, the method includes: Step 1, setting the wheel finite element model; Step 2, using transient contact fatigue simulation technology to build a rigid-flexible coupling dynamics simulation model; Step 3, setting nonlinear contact between the tire model and the hub in the simulation model to simulate the continuous load on the wheel to improve the simulation accuracy; Step 4: Output the fatigue life cloud diagram of the rim according to the transient stress result of one rotation of the wheel and the input fatigue stress life curve parameters of the rim material to analyze the fatigue life of the vehicle.

[0030] Step 4 includes the following steps.

[0031] Step 41, driving the hub to drive the wheel to rotate, and obtaining the transient stress result of the wheel vertically downward under the action of radial load; Step 42, selecting the transient stress result of one rotation of the wheel, inputting the fatigue stress life curve of the rim material, and simulating and calculating the fatigue life cloud diagram of the rim; like Fig. 9 As shown in the figure, the stress-life curve, also called SN curve or fatigue curve, is a curve that takes the fatigue strength of a material standard specimen as the ordinate and the logarithm of the fatigue life lg N as the abscissa, and represents the relationship between the fatigue strength and fatigue life of a standard specimen under certain cycle characteristics.

[0032] Step 43, outputting a rim fatigue life cloud diagram to analyze the vehicle fatigue life.

[0033] The present invention patent calculates the wheel fatigue life based on the requirements of GB / T 5909 "Performance Requirements and Test Methods for Commercial Vehicle Wheels". Since the regulations require more than 500,000 cycles, the rim fatigue life is greater than 500,000 cycles. Fig.10 As shown, the rim fatigue life is 1.993 million cycles, which is greater than the regulatory requirement of more than 500,000 cycles.

[0034] The present invention provides a wheel fatigue life analysis method based on transient contact fatigue simulation technology, which is mainly used to solve the technical problems existing in the prior art, such as missing the peak stress in the wheel rotation process and not considering the influence of tire pressure. The technical solution adopts transient nonlinear contact fatigue simulation technology, builds a rigid-flexible coupling dynamic model in multi-body dynamics software, sets up nonlinear contact between the tire model and the rotating drum in the simulation model, and simulates the force of the tire pressure on the rim, thereby ensuring the consistency of the simulation and the actual bench test, improving the simulation accuracy and the efficiency of building the simulation model, and saving the wheel fatigue life analysis cycle.

[0035] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A wheel fatigue life analysis method based on transient contact fatigue simulation technology, characterized in that: The method comprises: Step 1, setting the wheel finite element model; Step 2, using transient contact fatigue simulation technology to build a rigid-flexible coupling dynamics simulation model; Step 3, setting nonlinear contact between the tire model and the hub in the simulation model to simulate the continuous load on the wheel to improve the simulation accuracy; Step 4: Output the fatigue life cloud diagram of the rim according to the transient stress result of one rotation of the wheel and the input fatigue stress life curve parameters of the rim material to analyze the fatigue life of the vehicle.

2. The wheel fatigue life analysis method based on transient contact fatigue simulation technology according to claim 1 is characterized in that: The step 1 comprises: Step 11, setting the basic size of the tire and rim finite element model to L, and using the hexahedral unit type; Step 12, setting the tire and rim fitting surface areas to be in contact connection; Step 13, setting the tire internal pressure P and adjusting the elastic modulus of the tire material so that the radial stiffness of the wheel is consistent with the design value.

3. The wheel fatigue life analysis method based on transient contact fatigue simulation technology according to claim 2 is characterized in that: The basic size of the finite element model is L=5 mm.

4. The wheel fatigue life analysis method based on transient contact fatigue simulation technology according to claim 2 is characterized in that: The tire internal pressure P=2.5 bar.

5. The wheel fatigue life analysis method based on transient contact fatigue simulation technology according to claim 1 is characterized in that: The step 2 comprises: Step 21, establishing a hub table model; Step 22, importing the tire and rim assembly finite element model; Step 23, generating a wheel assembly flexible body file and establishing a wheel flexible body model.

6. The wheel fatigue life analysis method based on transient contact fatigue simulation technology according to claim 1 is characterized in that: The step of setting the nonlinear contact between the tire model and the rotating hub comprises: Step 31, setting the outer surface of the flexible tire model as a contact surface as Setpatch1; Step 32, setting the outer surface of the rigid body hub as the contact surface as FaceSurface1; Step 33, setting the above two contact surfaces in contact relationship as a pair of contact surfaces.

7. The wheel fatigue life analysis method based on transient contact fatigue simulation technology according to claim 1 is characterized in that: The simulated continuous load on the wheel includes: Step 34, applying a radial load perpendicular to the ground and downward to the wheel center to drive the hub to rotate; Step 35, driving the wheel to rotate under the action of radial load and friction between the tire and the hub, simulating the continuous load on the wheel to avoid missing the peak stress during the wheel rotation process.

8. The wheel fatigue life analysis method based on transient contact fatigue simulation technology according to claim 1 is characterized in that: The step 4 comprises: Step 41, driving the hub to drive the wheel to rotate, and obtaining the transient stress result of the wheel vertically downward under the action of radial load; Step 42, selecting the transient stress result of one rotation of the wheel, inputting the fatigue stress life curve of the rim material, and simulating and calculating the fatigue life cloud diagram of the rim; Step 43, outputting a rim fatigue life cloud diagram to analyze the vehicle fatigue life.

9. The wheel fatigue life analysis method based on transient contact fatigue simulation technology according to claim 8 is characterized in that: The rim fatigue life is greater than 500,000 cycles.

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