Modal testing of a smooth tire in low and medium frequency- estimation of structural parameters

The noise generated by tire vibrations of a vehicle rolling above 80 Km/h on a rough surface represents the largest component of the total noise generated by the vehicle. In urban conditions, it can be a source of great annoyance. Consequently, the reduction of tire-road noise emission is a very important issue. The study focused on aspect of tire belt vibrations in the noise generation mechanism. In order to predict the rolling noise of a tire, a dynamical model is necessary. A linear model of a smooth tire at rest based on superposition modal principle is thus described. Modal parameters of the tested tire are identified in the frequency domain with a global curve-fitting method. Various problems related to the technique of experimental modal testing on tires have been identified. An updated procedure has been performed to improve the model prediction compared to the measurements. The study goes deeply into several aspects of the vibration of unloaded smooth tires.