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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.

Airflow resistivity is one of the most important parameters in the study of the physical properties of porous acoustic materials. This parameter is fundamental for the correct evaluation of sound absorption of acoustic materials and is needed in all the theoretical models. In the present work, airflow resistivity of porous materials is determined under effective operating conditions inside a vehicle (temperature, compression of the panels). Starting from the discussion on the measurement uncertainty, experimental data of airflow resistivity, measured as a function of temperature and applied static loads, are presented. By introducing the measured values in a SEA model of a typical vehicle panel, the foreseen values of acoustic absorption due to variation of temperature and static load are determined and presented.