Today's tire design is quite challenging since it implies to satisfy often conflicting targets like reduced fuel consumption, improved wet braking, low noise emission, high hydroplaning resistance, long wear life, etc., just to mention some of them. At the design phase, tire designers are used to set constraints to some main tire features like contact patch shape, pressure and stiffness distribution, in order to guarantee the achievement of the desired performances. But what does it happen to these design factors during tire life-cycle? And what does it happen to the tire performances during tire life-cycle? From the viewpoint of safety and product quality, it is important for a tire supplier to assure that the optimal equilibrium reached in the system vehicle/tires at the end of their development undergoes as few variations as possible during the mileage: hence it becomes of primary importance not only the performance itself, but also its 'robustness'. To verify the tire performances at different stage of life-cycle, physical prototypes have to be built and experimental wear tests, in both indoor and outdoor conditions, are required before getting the final assessments. In this context, the prediction by simulation of the tire wear evolution becomes a milestone to analyze the tire performances in its life-cycle, reducing the tire development time as well as its costs by a great amount, and matching the customers' needs of short development time and exigent performances targets. It's possible in this way to accelerate the development of new tire design concepts to control the robustness of tire performances. The purpose of this work is to summarize such a prediction technology. Steady-state FEM simulation is used here to study in a virtual environment the evolution of wear profile: simulation is based on tread outer material removal by adapting the tire tread mesh during the calculation. Rubber abrasion resistance and surface friction effects can be taken into account in a practical way by efficient abrasion and friction model, whose parameters can be extracted by a set of laboratory tests under different boundary conditions like load, speed, surface type, temperature, aging. Tire simulation conditions are extracted by an in-house developed procedure based on the characterization of the wear course and vehicle. Validations by indoor drum measurements give further reliability to the prediction tool. By means of vehicle modeling, it is possible to get predictions considering different vehicle types. In this way, input to the tires will depend also on vehicle/suspensions as well as on the severity of the testing track or the driving style.
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