A finite element based approach to characterising flexible ring tire (FTire) model for extended range of operating conditions

In order to accurately predict vehicle dynamic properties when tires impact high obstacles or large bumps, appropriate tire models need to be developed and characterised. The Flexible Ring Tire (FTire) model is one of the models for predicting the transient dynamic responses when traversing obstacles. In this thesis, a combination of experimental tests and Finite Element (FE) modelling is used in deriving FTire models for different levels of tire/road interaction severity. A FE tire model is built to characterize tire properties including static properties, steady-state rolling properties and transient dynamic rolling properties. A 235/60 R18 tire is cut in order that the tire cross-section can be captured and the tire rubber and reinforcement components can be extracted. A detailed method for the determination of geometrical and material properties of tires has been developed for tire modelling. The 2D and 3D models for static and dynamic analysis are both developed using a commercial FE code ABAQUS. The parameters of FTire model are derived based on the experimental data and FE simulation data, and different FTire models are derived under different operation conditions. Multi-body dynamic analysis is carried out using these FTire models, and the transient dynamic responses using different FTire models are compared with each other. It is shown that FE modelling can be used to accurately characterise the behaviour of a tire where limitations in experimental facilities prevent tire characterisation using the required level of input severity in physical tests.