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The time to market in the automotive industry is constantly decreasing pushing the carmaker companies to increase the efforts in numerical simulations and to decrease the number of prototypes. In the NVH field, this time constraint reflects in moving the well-established finite element simulations towards the so called “full-vehicle simulations”. Specifically, the CAE techniques should be able to predict the complete behavior of the vehicles in mission conditions, so to reproduce some usual tests, such as the “coast down” test on different roads. The aim of this paper is to present a methodology to improve rolling noise simulations exploiting an integrated full-vehicle approach. An accurate modeling of all the subsystems is needed, with particular attention to the wheels and the suspension systems. Therefore, the paper firstly covers the modeling approach used to obtain the FE models of tires and suspension system.

Within the automotive industry, a typical way to account for tires in a roadnoise mission simulation is to use the “modal model” supplied by tire manufacturers. Even though this kind of models is certified by the suppliers and is very simple to use, it has the drawback to be disconnected from the physical description of the tire. This reflects in limiting the carmaker company to be able only to request certain modal characteristics to the supplier. The aim of this paper is to present an accurate, yet easy to use, methodology to develop an FE model of a tire, to be used in a full-vehicle simulation. The determined model must be connected to the tire physical properties. These properties are not measured directly, but determined by tuning a properly created geometric FE model to the measured point inertances of the inflated tire. This allows creating the model only by using an optimization algorithm to tune such properties.