【摘要】：汽車在行駛過程中,不可能一直勻速直線地行駛在良好路面上,一般總是要轉(zhuǎn)彎,要經(jīng)歷不平的路面,有時候還要在干路面,冰雪路面,滑水路面等不同路面行駛,輪胎總是在非穩(wěn)態(tài)工況下運動,輪胎的側(cè)向速度,路面狀況(摩擦系數(shù)),輪胎與路面間的垂向力時刻在變化,這些因素都影響著輪胎的側(cè)向力學(xué)特性,也直接影響著汽車的操穩(wěn)特性,所以研究輪胎的側(cè)向非穩(wěn)態(tài)力學(xué)特性十分重要,建立能夠表達(dá)復(fù)雜工況下輪胎力學(xué)特性的輪胎非穩(wěn)態(tài)模型更是具有重大實際意義。本文主要研究多種復(fù)雜側(cè)偏工況下輪胎的非穩(wěn)態(tài)力學(xué)特性,通過設(shè)計并實現(xiàn)大量非穩(wěn)態(tài)試驗,必要時用有限元虛擬試驗的手段,在已有Uni Tire半經(jīng)驗非穩(wěn)態(tài)模型的基礎(chǔ)上進(jìn)行完善處理,然后與PAC2012模型、試驗數(shù)據(jù)進(jìn)行對比,驗證其表達(dá)能力和精度。論文首先設(shè)計并實現(xiàn)了研究本文輪胎模型中所用到的全部輪胎力學(xué)特性試驗,有純側(cè)偏工況下的穩(wěn)態(tài)試驗,側(cè)向剛度試驗,接地印跡測量試驗,這些試驗為后續(xù)非穩(wěn)態(tài)建模提供必須的參數(shù);還有側(cè)偏角階躍工況下的非穩(wěn)態(tài)試驗,以及比較創(chuàng)新的路面摩擦系數(shù)突變狀態(tài)下的側(cè)偏非穩(wěn)態(tài)試驗和垂向載荷變化的側(cè)偏非穩(wěn)態(tài)試驗,目的是分析這些復(fù)雜工況下的輪胎側(cè)向力學(xué)特性,并為驗證輪胎模型的精度提供重要依據(jù)。具體從以下幾方面闡述:輪胎力學(xué)特性研究的意義,試驗設(shè)備的簡述,試驗方案的制定與執(zhí)行,試驗結(jié)果曲線的輸出,以及對試驗現(xiàn)象的分析說明。然后介紹分析了PAC2012模型的建模機(jī)理,PAC2012模型一直被業(yè)界所認(rèn)可,廣泛應(yīng)用于各種汽車動力學(xué)軟件中,是公認(rèn)的精度較高的經(jīng)驗?zāi)Ｐ?所以PAC2012模型也作為本文研究的參照。簡要介紹了PAC2012模型的發(fā)展歷史,分析了其穩(wěn)態(tài)建模特點,并詳細(xì)研究了非穩(wěn)態(tài)建模過程,包括線性非穩(wěn)態(tài)及非線性非穩(wěn)態(tài)建模分析。并結(jié)合上一章的輪胎力學(xué)特性試驗,驗證PAC2012模型的表達(dá)精度。再次從輪胎坐標(biāo)系,輸入輸出,核心公式及參數(shù)等角度,介紹了Uni Tire輪胎半經(jīng)驗?zāi)Ｐ偷姆�(wěn)態(tài)建模知識。又以一種全新的方法建立Uni Tire輪胎非穩(wěn)態(tài)模型:將輪胎簡化成胎面阻尼和胎體彈簧、胎體阻尼串聯(lián)的結(jié)構(gòu),建立任意時刻動力學(xué)方程,并進(jìn)行理論求解,得到該時刻的輪胎變形,最后建立輪胎非穩(wěn)態(tài)模型的表達(dá)式。依據(jù)試驗和有限元仿真結(jié)果,分析路面摩擦系數(shù)突變和垂向載荷變化狀態(tài)下輪胎非穩(wěn)態(tài)力學(xué)特性的特點,完善了Uni Tire輪胎半經(jīng)驗非穩(wěn)態(tài)模型。最后主要進(jìn)行模型的對比驗證工作,將Uni Tire輪胎半經(jīng)驗非穩(wěn)態(tài)模型與試驗數(shù)據(jù)、PAC2012模型進(jìn)行全方位對比,驗證Uni Tire輪胎半經(jīng)驗非穩(wěn)態(tài)模型的表達(dá)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.
【學(xué)位授予單位】：吉林大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2016
【分類號】：U463.341

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2 付晶晶;基于輪胎設(shè)計參數(shù)的UniTire建模方法研究[D];吉林大學(xué);2013年

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本文編號：2375097