Rapid calculation method and system for friction work of periodic complex pattern tire and computer program

Abstract

The invention relates to the technical field of tire simulation design, in particular to a rapid calculation method and system for friction work of a periodic complex pattern tire and a computer program. According to the method, the implicit finite element method is adopted for numerical simulation, and compared with a traditional explicit finite element method, the calculation efficiency is improved by about 100 times, and the calculation precision is improved by at least 10%. According to the method, the friction work of the tire with periodic complex patterns can be rapidly and accurately calculated, the analysis efficiency and precision are greatly improved, and powerful technical support is provided for tire pattern design and structure optimization.

Description

Technical Field

[0001] The invention relates to the technical field of tire simulation design, and in particular to a method, system and computer program for quickly calculating the friction work of a tire with periodic complex patterns. Background Art

[0002] With the popularity of electric vehicles, the wear rate of tires has significantly accelerated, prompting the development of high-wear-resistant tires to become an industry consensus. The wear life of tires is one of the key indicators to measure their performance, which directly affects the safety, economy and environmental friendliness of the vehicle.

[0003] At present, the evaluation of tire wear life mainly relies on test methods and finite element simulation methods. The test method can obtain tire wear life data through actual testing, but its disadvantage is that it requires the production of actual tires and long-term testing, which is costly and has a long cycle. In addition, the test method is difficult to obtain the deformation and stress state information inside the tire, and multiple tests are required for tires with different structures, which is inefficient.

[0004] In contrast, the finite element simulation method has become an important tool for evaluating tire wear life due to its low cost, short cycle, and ability to intuitively display the deformation and stress state of the tire. Finite element simulation is usually used to calculate the friction work of the tire tread to characterize the wear resistance of the tire. However, existing simulation studies mainly focus on smooth tires or longitudinal groove tires, and there are fewer studies on the calculation of friction work of tires with complex periodic patterns. Complex patterns break the traditional axisymmetric structure, resulting in discontinuity of finite element unit data and difficulty in effective data processing. If existing methods want to obtain the friction work data of a complete cycle of the tire, they usually need to perform full-wheel rolling calculations based on the explicit finite element method, which not only consumes huge computing resources and time, but also has low calculation accuracy.

[0005] In addition, with the increasing demand for high-performance tires, the applicant's previous applications for Chinese invention patent applications (such as Patent 2021116135564, Patent 2022100923567 and Patent 2022105620611) also proposed several simulation analysis methods for tire performance. The existing explicit finite element method can no longer meet the requirements of quickly and accurately calculating the friction work of tires with complex patterns. Therefore, there is an urgent need for a fast calculation method for tire friction work that can significantly improve the calculation efficiency while ensuring the calculation accuracy, so as to support pattern design and tire structure optimization. Summary of the invention

[0006] In order to solve the above-mentioned technical problems, the purpose of the present invention is to provide a method for quickly calculating the friction work of a periodic complex pattern tire. The method can be calculated using an implicit finite element method. Only a simple rolling calculation of an intercept angle is required to quickly and accurately calculate the friction work of a complex pattern tire, which greatly improves the analysis efficiency and accuracy and provides guidance for pattern design and tire structure design.

[0007] In order to achieve the above-mentioned purpose, the present invention adopts the following technical solutions: A method for quickly calculating the friction work of a tire with a periodic complex pattern comprises the following steps: 1) Perform static load numerical simulation on tires with periodic complex patterns, apply rated air pressure and load to the tire model, establish a road model and apply corresponding loads to make the road press against the tire; 2) Perform a steady-state rolling numerical simulation on the above tire, set the actual test road friction coefficient, apply the rotational angular velocity ω around the wheel axis and the straight-line speed v, and determine the rotational angular velocity ω manually or by program trial method; 3) Based on the steady-state rolling calculation, the angular displacement around the wheel axis and the horizontal displacement in the opposite direction are applied to output the friction and slip data between the tread and the road surface at each step; 4) Extract the friction and slip data of the nodes and record the force history of each node at different calculation steps; 5) Based on the extracted data, calculate the friction work of the tread nodes using the formula: ; Where n is the number of calculation steps in the third step, i is the node number of the original intercept in the fourth step, F 1,i,n is the friction force of node i along the driving direction at the nth step, S 1,i,n is the slip distance of node i along the driving direction at the nth step; F 2,i,n is the friction force perpendicular to the driving direction at node i at step n, S 2,i,n is the sliding distance of node i in the direction perpendicular to the driving direction at the nth step.

[0008] Preferably, the static load numerical simulation step further comprises: applying a rated air pressure of 0.18 MPa and a rated load of 6000 N to the tire model.

[0009] Preferably, the steady-state rolling numerical simulation step further comprises: setting the road friction coefficient between 0.5 and 1.5, and the straight-line driving speed v Set within the range of 40km / h to 120km / h, the rotation angular speedω It needs to be determined manually or by trial and error. The criterion is that the torque value M around the axle at the output axle is less than 5N·mm.

[0010] Preferably, the angular displacement about the wheel axis is applied θ is the angle value of a single intercept of the tire pattern, and the horizontal displacement d The calculation formula is: ; Where r is the tire load radius.

[0011] Preferably, the step of extracting node data includes: the node number of the original intercept of the tire is i , the node number offset values ​​of other intercepts are p , the number of unit intercepts is n , numbered k The node in the second step t The segment output result is recorded as the node number k%p In the node force history of x Denoted as (int( k / p)*θ+t*θ / 10 ), where % represents modulo, int() represents integer, and the ordinate is the absolute value of the friction force F1 and the slip distance S1 of the node along the driving direction, and the absolute value of the friction force F2 and the slip distance S2 in the direction perpendicular to the driving direction.

[0012] Preferably, the friction work calculation step further comprises: accumulating the friction force and sliding distance of each node within 10 calculation steps to obtain the total friction work of the node.

[0013] Furthermore, the present invention also provides a system for implementing the method, comprising: a computing unit for performing numerical simulations of static loads and steady-state rolling; a data processing unit for extracting friction and slip data of nodes; a calculation module for calculating the friction work of the tread nodes based on the extracted data; A display unit is used to show the calculation results and the friction work distribution diagram.

[0014] Preferably, the calculation unit is configured as a software module based on the implicit finite element method, so as to improve the calculation accuracy and efficiency; and / or, the data processing unit further includes a node number management module, so as to accurately extract the force history data of each node according to the node number and the offset value.

[0015] Furthermore, the present invention also provides a computer-readable storage medium having a computer program or instruction stored thereon, and the method is implemented when the computer program or instruction is executed by a processor.

[0016] Furthermore, the present invention also provides a computer program product, comprising a computer program or instructions, which implement the method when executed by a processor.

[0017] The present invention has the following technical effects due to the adoption of the above technical solution: 1. Significantly improve calculation efficiency: The present invention uses implicit finite element method to calculate tire friction work, which improves calculation efficiency by about 100 times compared with the existing calculation method based on explicit finite element method. Only one intercept angle needs to be rolled to quickly obtain the friction work data of a complete circle of tires, which greatly shortens the calculation cycle and significantly improves work efficiency.

[0018] 2. Improve calculation accuracy: By using the implicit finite element method, the present invention improves calculation accuracy by at least 10% while ensuring calculation speed. Such high-precision calculation results can more accurately reflect the friction performance of tires under actual working conditions and provide reliable data support for tire design.

[0019] 3. Effectively process complex periodic patterns: Complex periodic patterns usually break the traditional axisymmetric structure, resulting in discontinuous finite element unit data and difficulty in effective data processing. The method of the present invention can overcome this technical difficulty, and through simplified rolling calculation steps, smoothly process tire models with complex patterns and ensure accurate calculation of friction work.

[0020] 4. Reduced computational costs: Compared with traditional test methods and explicit finite element methods, the method of the present invention greatly reduces the demand for computing resources and time, significantly reducing R&D costs. Without the need for multiple expensive and time-consuming actual tire tests, tire wear life-related data can be quickly obtained through numerical simulation.

[0021] In summary, the present invention solves the problems of low efficiency and insufficient accuracy in calculating the friction work of complex pattern tires in the prior art by adopting an innovative implicit finite element calculation method. It has significant technical advantages and broad application prospects, and can effectively promote the development and innovation of tire technology. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a 21550R15 tire model with complex tread patterns; Figure 2 This is the load deformation diagram of 21550R15 tire with complex tread pattern; Figure 3It is a schematic diagram of the rotation axis, rim angular displacement and tread-road friction of a 21550R15 tire; Figure 4 It is the single tread intercept model of 21550R15 tire; Figure 5 This is a schematic diagram of the intercept angle of a single tread pattern of a 21550R15 tire; Figure 6 It is the node numbered 153900656 in the 21550R15 tire model; Figure 7 The friction data of node 900639 in the 21550R15 tire model; Figure 8 It is the slip distance data of node 900639 in the 21550R15 tire model; Fig. 9 Friction work distribution of 21550R15 tire intercept.

[0023] Figure 1 In the figure, 1: tire model with periodic pattern, 2: wheel rim, 3: road surface model, 4: load applied to the road surface; Figure 2 In the middle, 5: complex tread pattern, 6: rim fixing the structure, 7: deformed tire; Figure 3 In the middle, 8: tread, 9: road surface, 10: rotation axis of the tire, 11: angular displacement of the rim rotation; Figure 5 In, 12: Delay intercept angle (10°). DETAILED DESCRIPTION

[0024] The following is a clear and complete description of the technical solutions in the embodiments of the present invention in conjunction with 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.

[0025] The present invention provides a method for quickly calculating the friction work of a tire with a periodic complex pattern, comprising the following steps: The first step is to perform static load numerical simulation on the tire with periodic pattern. Apply rated air pressure to the tire model with periodic pattern, establish a road model, fix the rim, and apply rated load to the road surface to press it against the tire; The second step is to perform a steady-state rolling numerical simulation on the tire with periodic patterns. Set the road friction coefficient to the actual test value (between 0.5 and 1.5), and apply the rotational angular velocity around the wheel axle to each unit and wheel axle reference point of the tire model with periodic patterns. ω , and straight-line speed v , vThe value is set according to actual needs (usually 40 km / h ~120 km / h ), angular velocity ω It needs to be determined manually or by trial and error. The criterion is that the torque value around the axle at the output axle is M<5N·mm. The third step is to apply an angular displacement of rotation around the wheel axis to the rim based on the calculation results of the second step. θ , θ is the angle value of a single intercept of the tire pattern, and at the same time applies a horizontal displacement to the road surface in the opposite direction of the rim rotation d , d Calculate as follows:

[0026] in r is the tire load radius. The calculation process is divided into 10 steps, and the friction and slip data between the tread and the road surface are output at each step.

[0027] The fourth step is to extract the friction and slip data of the nodes. The node number of the tire original intercept is i , the node number offset values ​​of other intercepts are p , the number of unit intercepts is n , numbered k The node in the second step t The segment output result is recorded as the node number k%p In the node force history of x Denoted as (int( k / p)*θ+t*θ / 10 ), where % represents modulus, int() represents integer, and the ordinate is the absolute value of the friction force F1 and the sliding distance S1 of the node along the driving direction, and the absolute value of the friction force F2 and the sliding distance S2 in the direction perpendicular to the driving direction; Step 5: Calculate the friction work of the tread nodes. Calculate the friction work data of the nodes according to the following formula:

[0028] Where n is the number of calculation steps in the third step 10, i is the node number of the original intercept in the fourth step, F 1,i,n is the friction force of node i along the driving direction at the nth step, S 1,i,n is the slip distance of node i along the driving direction at the nth step.

[0029] Taking the 21550R15 tire as an example, the optimal implementation mode of the present invention is described in detail: The first step is to perform static load numerical simulation on the tire with periodic pattern. According to the "China Tire Rim Valve Yearbook", the rated air pressure of 0.18MPa and rated load are applied to the tire model with periodic pattern, the road surface model is established, and the rim is fixed. Figure 1 As shown, Figure 1 Reference numeral 1; having a periodic pattern tire model, 2: rim, 3: road model, 4: the load applied to the road surface; the rated load 6000N is applied to the road surface, so that it is pressed against the tire, such as Figure 2 As shown, Figure 2 In the figure, 5: complex tread pattern, 6: the structure for fixing the rim, 7: deformed tire.

[0030] The second step is to perform a steady-state rolling numerical simulation on the tire with periodic patterns. The road friction coefficient is set to the actual test value of 0.7, and the rotation angular velocity around the wheel axle is applied to each unit and wheel axle reference point of the tire model with periodic patterns. ω ,like Figure 3 , Figure 3 Reference numerals 8: tread, 9: road surface, 10: rotation axis of the tire, 11: angular displacement of the rim; and straight-line speed v =60 km / h , angular velocity ω It is necessary to use the program trial method to determine that it is 54.32rad / s. At this time, the torque value around the axle at the wheel axle is M=3.6N·mm.

[0031] The third step is to apply an angular displacement of rotation around the wheel axis to the rim based on the calculation results of the second step. θ=10° , θ is the angle value of a single intercept of the tire tread, such as Figure 4 and Figure 5 As shown, Figure 5 Reference numeral 12: Delay intercept angle (10°). At the same time, a horizontal displacement in the opposite direction of the rim rotation is applied to the road surface. d , d Calculate as follows:

[0032] in r=278.05mm is the tire load radius, calculated d =48.53mm. The calculation process is divided into 10 steps, and the friction and slip data between the tread and the road surface are output at each step.

[0033] The fourth step is to extract the friction and slip data of the node. Take the node numbered 153900656 as an example (e.g. Figure 6 ), the node number offset values ​​of other intercepts are p=9000001， The node numbers for the tire raw intercept arei=900639 , the number of intercepts is n=36 , the node numbered 153900656 is the first 1 The segment output result is recorded as the node number 900639 In the node data history, its section is 17, and its horizontal coordinate x Recorded as (17 *10+1*10 / 10 ) = 171, the node numbered 162900257 is the first 18 The segment output result is recorded as the node number 900639 In the node force history of x Recorded as (18 *10+5*10 / 10 ) = 185, the ordinate is the friction force and sliding distance of the node (including along the driving direction and perpendicular to the driving direction), which are recorded as F value and S value respectively. Taking F1 as an example, this value is 0.13. Extract 900639 All the calculation results of the nodes are plotted as curves. Figure 7 and Figure 8 As shown in the figure, it can be seen that only the contact position with the road surface has friction and sliding distance data.

[0034] Step 5: Calculate the friction work of the tread nodes. Calculate the friction work data of the nodes according to the following formula:

[0035] Where n is the number of calculation steps in the third step 10, i is the node number of the original intercept in the fourth step, F 1,i,n is the friction force of node i along the driving direction at the nth step, S 1,i,n For Node i In the n The slip distance along the driving direction when walking; F 2,i,n is the friction force of node i in the lateral direction (perpendicular to the driving direction) at step n, S 2,i,n is the sliding distance of node i in the lateral direction (perpendicular to the driving direction) at step n. i = 900639 As an example, the calculated W 900639 =5.52mJ. The friction work of the tire pattern is Fig. 9 As shown, it can be seen that the shoulders of the pattern will wear faster, while the center will wear slower.

[0036] According to the above method, the friction work of a tire with a periodic pattern can be calculated, and the entire calculation time is about 0.8 hours. If the friction work is calculated by rolling the tire model once, the calculation time is about 100 times that of the method of the present invention, and the data processing time will exceed 36 times that of the method of the present invention. This proves the advanced nature of the method of the present invention.

[0037] The above is a description of the embodiments of the present invention. Through the above description of the disclosed embodiments, professionals and technicians in the field can implement or use the present invention. Various modifications to these embodiments will be apparent to professionals and technicians in the field. The general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to these embodiments shown in this article, but will conform to the widest range consistent with the principles and novelties disclosed herein.

Claims

1. A method for quickly calculating the friction work of a tire with a periodic complex pattern, characterized in that: The following steps are involved: 1) Perform static load numerical simulation on tires with periodic complex patterns, apply rated air pressure and load to the tire model, establish a road model and apply corresponding loads to make the road press against the tire; 2) Perform steady-state rolling numerical simulation on the above tires, set the actual test road friction coefficient, and apply the rotation angular velocity around the wheel axis. ω Straight line speed v and determine the angular velocity manually or by trial and error ω ; 3) Based on the steady-state rolling calculation, apply the angular displacement around the wheel axis θ and the horizontal displacement in the opposite direction d , output the friction and slip data between the tread and the road surface at each step; 4) Extract the friction and slip data of the nodes and record the force history of each node at different calculation steps; 5) Based on the extracted data, calculate the friction work of the tread nodes using the formula: ； Where n is the number of calculation steps in the third step, i is the node number of the original intercept in the fourth step, F 1,i,n is the friction force of node i along the driving direction at the nth step, S 1,i,n is the slip distance of node i along the driving direction at the nth step; F 2,i,n is the friction force perpendicular to the driving direction at node i at step n, S 2,i,n is the sliding distance of node i in the direction perpendicular to the driving direction at the nth step.

2. The method according to claim 1, characterized in that The static load numerical simulation step further includes: applying a rated air pressure of 0.18 MPa and a rated load of 6000 N to the tire model.

3. The method according to claim 1, characterized in that The steady-state rolling numerical simulation step further includes: setting the road friction coefficient between 0.5 and 1.5, and the straight-line driving speed v Set within the range of 40km / h to 120km / h, the rotation angular speed ω It needs to be determined manually or by trial and error. The criterion is that the torque value M around the axle at the output axle is less than 5N·mm.

4. The method according to claim 1, characterized in that The applied angular displacement about the wheel axis θ is the angle value of a single intercept of the tire pattern, and the horizontal displacement d The calculation formula is: ； Where r is the tire load radius.

5. The method according to claim 1, characterized in that The step of extracting node data includes: the node number of the original intercept of the tire is i , the node number offset values ​​of other intercepts are p , the number of unit intercepts is n , numbered k The node in the second step t The segment output result is recorded as the node number k%p In the node force history of x Denoted as (int( k / p)*θ +t*θ / 10 ), where % represents modulo, int() represents integer, and the ordinate is the absolute value of the friction force F1 and the slip distance S1 of the node along the driving direction, and the absolute value of the friction force F2 and the slip distance S2 in the direction perpendicular to the driving direction.

6. The method according to claim 1, characterized in that The friction work calculation step further includes: accumulating the friction force and sliding distance of each node within 10 calculation steps to obtain the total friction work of the node.

7. A system for implementing the method according to any one of claims 1 to 6, characterized in that: include: a computing unit for performing numerical simulations of static loads and steady-state rolling; a data processing unit for extracting friction and slip data of nodes; a calculation module for calculating the friction work of the tread nodes based on the extracted data; A display unit is used to show the calculation results and the friction work distribution diagram.

8. The system according to claim 7, characterized in that The calculation unit is configured as a software module based on the implicit finite element method, which is used to improve the calculation accuracy and efficiency; and / or, the data processing unit further includes a node number management module, which is used to accurately extract the force history data of each node according to the node number and offset value.

9. A computer-readable storage medium having a computer program or instruction stored thereon, characterized in that: When the computer program or instruction is executed by a processor, the method according to any one of claims 1 to 6 is implemented.

10. A computer program product comprising a computer program or instructions, characterized in that When the computer program or instruction is executed by a processor, the method according to any one of claims 1 to 6 is implemented.

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