fem tyre modeling - tu/e v.d._2007.pdf · fem tyre modeling r. van der steen, i ... calculate the...
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FEM Tyre ModelingR. van der Steen, I. Lopez, H. Nijmeijer
Eindhoven University of TechnologyDepartment of Mechanical Engineering, Dynamics and Control Group
P.O. Box 513, 5600 MB Eindhoven, The Netherlandsphone: +31-(0)40-2474092, email: [email protected]
IntroductionIn the tyre industry FEM is adopted in the design pro-cess of new tyres. However in practice most modelsare still not able to accurately match experiments.Besides modeling the tyre itself, the interaction of thetyre with the road needs to be incorporated.The cornering, braking, traction, rolling resistanceand wear performance of a tyre depend on the gene-rated friction forces. Friction depends not only on thetread properties of the tyre, but also on the road sur-face and environmental conditions.
ObjectiveThe aim of this project is to gain more insight inmodeling of a tyre using FEM, with a focus on thedevelopment of a robust friction model which can cap-ture the interaction with the road.
Hysteretic frictionEarly studies have shown that rubber friction is re-lated to internal friction of the rubber and depends onthe complex elastic modulus E(ω) [1].Sliding with a constant velocity v over asphalt givesoscillations over a broad frequency range due to thesurface roughness. A method to take this into ac-count is presented in [2], where every length scale λcontributes with a different frequency (ω ∼ v/λ) to theglobal friction coefficient.
v
λ
−3 −2.5 −2 −1.5 −1 −0.5 0 0.5 1 1.5 20
0.5
1
1.5
2
2.5
log(v) [m/s]
µ
Figure 1: Road surface and friction curve.
Lat 100To develop and validate the model friction experi-ments are performed on a Laboratory Abrasion andskid Tester (LAT 100). On the LAT 100 a small solidrubber tyre is placed on a rotating disk, where thespeed, surface of the disk, load and temperature canbe varied and measured. The friction model will becoupled to a FE model of the sample wheel. Thesemodels will be validated with measured slip charac-teristics.
Figure 2: Sample wheel and Finite Element Model.
Tyre modelWith a tyre/road interaction model it is possible tocalculate the force and moment characteristics of atyre under different driving conditions, see figure 3.Dedicated experiments will be performed for valida-tion.
GeometryMaterial dataBoundary conditions
Roughnessparameters
INPUTS
INTERACTION MODEL
FEM MODEL
CONTACT MODEL
FootprintSlip3D Force &MomentTemperature
OUTPUTS
Figure 3: Schematic overview.
References1. Grosch, K.A. (1963) The relation between the friction and
visco-elastic properties of rubber, Proceedings of the RoyalSociety of London, Series A, 274(1356):21–39
2. Persson, B.N.J. (2001) Theory of rubber friction and contactmechanics, Journal of Chemical Physics, 115(8):3840–3861