Finite Element Analysis On Steady State Mechanics Of All Steel Radial Tire

Tire is a complicated structure with many kinds of rubbers, usually, thestudy on tire mechanics is based on some theories and experiment data, in recentyears, since lots of software that used for finite element analysis were developed,finite element method had been widely used for the research of tire mechanicsThe finite element tire model is a model that can describe tire structure indetail, that is, the mechanics of different rubbers and steels are expressed bycorresponding to expressions, which make the tire model more like a real tire.The finite element tire model can describe rubbers properties and also be used toanalyze the influence of different rubbers to tire mechanics.The finite element tire model of all steel radial tire 11.00R20-18PR hasbeen made using HyperMesh and ABAQUS. HyperMesh is used to mesh thecross-section of tire, and the data of elements and nodes will be exported withABAQUS input file format, in which finite element tire model can be made.There 19 kinds of materials consist of finite element tire model according tothe actual structure of all steel radial tire, such as tread, sidewall, shoulder,inner-liner, filler, belt etc. The geometric non-linearity, nonlinear rubberconstructive equations and the anisotropy of cord-rubber composite, nonlinearcontact boundary between tire model and ground have been taken into account inthis model, but contact boundary between tire model and rim is neglected.The contact between bead and rim is a non-linear boundary, which is notonly computationally expensive, but also convergent difficult. In order to neglectthis non-linear boundary, six degrees of freedom of bead outer edge nodes thatcontact with rim have been fixed, which replaces the contact condition betweenbead and rim. The ground is defined as rigid body, and all motions of ground aresimulated by controlling its node.According to actual condition, assembling rim will be simulated, whichmakes bead in working position, and then simulates inflation by putting ondistribution force on inner surface of elements. Thus, a static analysis can beperformed by using three dimension inflation tire modal. The thesis analyzes notonly the varieties of normal stress and shape of contact patch with differentvertical load and tire pressure, but also the varieties of longitudinal stiffness,lateral stiffness, turn stiffness with different vertical load and tire pressure.Steady state tire's mechanics is the mechanics that input variables are notdependent on time, and steady state tire's mechanics is the basis of the study onnon-steady state tire's mechanics. A steady-state rolling analysis is performed byusing steady-state transport in ABAQUS/Standard. The steady-state transportanalysis capability in ABAQUS/Standard uses a reference frame that is attachedto the axle of the rotating cylinder. An observer in this frame sees the cylinder aspoints that are not moving, although the material of which the cylinder is made ismoving through those points. This removes the explicit time dependence fromthe problem—the observer sees a fixed point anywhere, with material movingthrough it. Thus, the finite element mesh describing the cylinder in this frame ofreference does not undergo the large rigid body spinning motion.The tire's steady state mechanics has been analyzed in this thesis, such asthe relationship of longitudinal force and slip ratio, lateral force and slip angle,self-aligning torque and slip angle, lateral force and camber. The varieties ofnormal stress and shape of contact patch with different slip ratio, slip angle,camber have also been analyzed.