UniTire轮胎非稳态模型的精度验证与完善
发布时间：2018-12-12 18:35
【摘要】：汽车在行驶过程中,不可能一直匀速直线地行驶在良好路面上,一般总是要转弯,要经历不平的路面,有时候还要在干路面,冰雪路面,滑水路面等不同路面行驶,轮胎总是在非稳态工况下运动,轮胎的侧向速度,路面状况(摩擦系数),轮胎与路面间的垂向力时刻在变化,这些因素都影响着轮胎的侧向力学特性,也直接影响着汽车的操稳特性,所以研究轮胎的侧向非稳态力学特性十分重要,建立能够表达复杂工况下轮胎力学特性的轮胎非稳态模型更是具有重大实际意义。本文主要研究多种复杂侧偏工况下轮胎的非稳态力学特性,通过设计并实现大量非稳态试验,必要时用有限元虚拟试验的手段,在已有Uni Tire半经验非稳态模型的基础上进行完善处理,然后与PAC2012模型、试验数据进行对比,验证其表达能力和精度。论文首先设计并实现了研究本文轮胎模型中所用到的全部轮胎力学特性试验,有纯侧偏工况下的稳态试验,侧向刚度试验,接地印迹测量试验,这些试验为后续非稳态建模提供必须的参数;还有侧偏角阶跃工况下的非稳态试验,以及比较创新的路面摩擦系数突变状态下的侧偏非稳态试验和垂向载荷变化的侧偏非稳态试验,目的是分析这些复杂工况下的轮胎侧向力学特性,并为验证轮胎模型的精度提供重要依据。具体从以下几方面阐述:轮胎力学特性研究的意义,试验设备的简述,试验方案的制定与执行,试验结果曲线的输出,以及对试验现象的分析说明。然后介绍分析了PAC2012模型的建模机理,PAC2012模型一直被业界所认可,广泛应用于各种汽车动力学软件中,是公认的精度较高的经验模型,所以PAC2012模型也作为本文研究的参照。简要介绍了PAC2012模型的发展历史,分析了其稳态建模特点,并详细研究了非稳态建模过程,包括线性非稳态及非线性非稳态建模分析。并结合上一章的轮胎力学特性试验,验证PAC2012模型的表达精度。再次从轮胎坐标系,输入输出,核心公式及参数等角度,介绍了Uni Tire轮胎半经验模型的稳态建模知识。又以一种全新的方法建立Uni Tire轮胎非稳态模型:将轮胎简化成胎面阻尼和胎体弹簧、胎体阻尼串联的结构,建立任意时刻动力学方程,并进行理论求解,得到该时刻的轮胎变形,最后建立轮胎非稳态模型的表达式。依据试验和有限元仿真结果,分析路面摩擦系数突变和垂向载荷变化状态下轮胎非稳态力学特性的特点,完善了Uni Tire轮胎半经验非稳态模型。最后主要进行模型的对比验证工作,将Uni Tire轮胎半经验非稳态模型与试验数据、PAC2012模型进行全方位对比,验证Uni Tire轮胎半经验非稳态模型的表达能力和精度。
[Abstract]:In the course of driving, it is impossible for a car to keep running in a straight line at a constant speed on a good road surface. In general, it has to turn and go through rough roads. Sometimes, it has to travel on different roads, such as dry roads, ice and snow roads, water-skiing roads, and so on. The tire always moves under the unsteady condition, the lateral velocity of the tire, the road condition (friction coefficient), the vertical force between the tire and the road are changing, these factors all influence the lateral mechanical properties of the tire. Therefore, it is very important to study the lateral unsteady mechanical properties of tires, and it is of great practical significance to establish a tire unsteady model which can express the mechanical properties of tyres under complex working conditions. In this paper, the unsteady mechanical properties of tire under complex sideways are studied. A large number of unsteady tests are designed and realized, and the finite element virtual test is used when necessary. On the basis of the existing semi-empirical unsteady model of Uni Tire, it is improved and processed, and then compared with the PAC2012 model, the experimental data are compared to verify its expression ability and accuracy. First of all, the paper designs and implements all the tire mechanical characteristic tests used in this paper, including steady state test, lateral stiffness test and ground imprinting test. These experiments provide necessary parameters for subsequent unsteady modeling; There are also the unsteady state tests under the condition of the lateral deflection angle step, and the side unsteady tests under the condition of the abrupt change of the friction coefficient of the pavement and the lateral unsteady tests with the variation of the vertical load. The purpose of this paper is to analyze the lateral mechanical properties of tire under these complex working conditions and to provide an important basis for verifying the accuracy of tire model. From the following aspects: the significance of the study of tire mechanical properties, the brief description of the test equipment, the formulation and execution of the test plan, the output of the test result curve, and the analysis of the test phenomenon. Then the modeling mechanism of PAC2012 model is introduced and analyzed. The PAC2012 model has been recognized by the industry and is widely used in various automotive dynamics software. It is recognized as an empirical model with high accuracy. So the PAC2012 model is also used as a reference in this paper. This paper briefly introduces the development history of PAC2012 model, analyzes the characteristics of its steady-state modeling, and studies in detail the process of unsteady modeling, including linear unsteady-state modeling and nonlinear unsteady-state modeling analysis. The precision of the PAC2012 model is verified by the tire mechanics test in the previous chapter. From the angle of tire coordinate system, input and output, core formula and parameters, the steady state modeling knowledge of Uni Tire tire semi-empirical model is introduced. The unsteady model of Uni Tire tire is established by a new method: the tire is simplified into a structure of tread damping and body spring, and the damping of the tire is in series, and the dynamic equation at any time is established, and the theoretical solution is carried out. The tire deformation at this time is obtained, and the expression of tire unsteady state model is established. Based on the experimental and finite element simulation results, the characteristics of unsteady mechanical properties of tire under the condition of sudden change of pavement friction coefficient and variation of vertical load are analyzed, and the semi-empirical unsteady model of Uni Tire tire is improved. In the end, the semi-empirical unsteady model of Uni Tire tire is compared with the experimental data and PAC2012 model to verify the expression ability and accuracy of the semi-empirical unsteady model of Uni Tire tire.
【学位授予单位】：吉林大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：U463.341
本文编号：2375097
[Abstract]:In the course of driving, it is impossible for a car to keep running in a straight line at a constant speed on a good road surface. In general, it has to turn and go through rough roads. Sometimes, it has to travel on different roads, such as dry roads, ice and snow roads, water-skiing roads, and so on. The tire always moves under the unsteady condition, the lateral velocity of the tire, the road condition (friction coefficient), the vertical force between the tire and the road are changing, these factors all influence the lateral mechanical properties of the tire. Therefore, it is very important to study the lateral unsteady mechanical properties of tires, and it is of great practical significance to establish a tire unsteady model which can express the mechanical properties of tyres under complex working conditions. In this paper, the unsteady mechanical properties of tire under complex sideways are studied. A large number of unsteady tests are designed and realized, and the finite element virtual test is used when necessary. On the basis of the existing semi-empirical unsteady model of Uni Tire, it is improved and processed, and then compared with the PAC2012 model, the experimental data are compared to verify its expression ability and accuracy. First of all, the paper designs and implements all the tire mechanical characteristic tests used in this paper, including steady state test, lateral stiffness test and ground imprinting test. These experiments provide necessary parameters for subsequent unsteady modeling; There are also the unsteady state tests under the condition of the lateral deflection angle step, and the side unsteady tests under the condition of the abrupt change of the friction coefficient of the pavement and the lateral unsteady tests with the variation of the vertical load. The purpose of this paper is to analyze the lateral mechanical properties of tire under these complex working conditions and to provide an important basis for verifying the accuracy of tire model. From the following aspects: the significance of the study of tire mechanical properties, the brief description of the test equipment, the formulation and execution of the test plan, the output of the test result curve, and the analysis of the test phenomenon. Then the modeling mechanism of PAC2012 model is introduced and analyzed. The PAC2012 model has been recognized by the industry and is widely used in various automotive dynamics software. It is recognized as an empirical model with high accuracy. So the PAC2012 model is also used as a reference in this paper. This paper briefly introduces the development history of PAC2012 model, analyzes the characteristics of its steady-state modeling, and studies in detail the process of unsteady modeling, including linear unsteady-state modeling and nonlinear unsteady-state modeling analysis. The precision of the PAC2012 model is verified by the tire mechanics test in the previous chapter. From the angle of tire coordinate system, input and output, core formula and parameters, the steady state modeling knowledge of Uni Tire tire semi-empirical model is introduced. The unsteady model of Uni Tire tire is established by a new method: the tire is simplified into a structure of tread damping and body spring, and the damping of the tire is in series, and the dynamic equation at any time is established, and the theoretical solution is carried out. The tire deformation at this time is obtained, and the expression of tire unsteady state model is established. Based on the experimental and finite element simulation results, the characteristics of unsteady mechanical properties of tire under the condition of sudden change of pavement friction coefficient and variation of vertical load are analyzed, and the semi-empirical unsteady model of Uni Tire tire is improved. In the end, the semi-empirical unsteady model of Uni Tire tire is compared with the experimental data and PAC2012 model to verify the expression ability and accuracy of the semi-empirical unsteady model of Uni Tire tire.
【学位授予单位】：吉林大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：U463.341
【相似文献】
相关硕士学位论文 前2条
1 李古建;UniTire轮胎非稳态模型的精度验证与完善[D];吉林大学;2016年
2 付晶晶;基于轮胎设计参数的UniTire建模方法研究[D];吉林大学;2013年
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