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There is a great lack of Brazilian laboratory and field measurements on of noise generated by the interaction between tyre and road surface. In this study the tyre-road noise interaction on Brazilian roads through the CPX method with a wheeled trailer with enclosure that simulates a light vehicle of 700 kg equipped with two tyres and two microphones for each tyre is evaluated. Two types of sections of the road with different surfaces characteristics were evaluated with the trailer at speed of 80 km/h. The first section road is comprised of a rubberized asphalt mixture about 30 months of age and the other surface is composed of an ordinary dense asphalt mixes with approximately 10 years of age. The noise generated by the tyre-road showed that the sound pressure levels are concentrated between 630 and 1600 Hz and the differences in the sound levels are related with the characteristics and ages of the road surface.

Currently, the use of numerical and analytical tools during a vehicle development is extensive in the automotive industry. This assures that the required performance levels can be achieved from the early stages of development. However, there are some aspects of the vibro-acoustic performance of a vehicle that are rarely assessed through numerical or analytical analysis. An example is the modeling of sound transmission through vehicle sealing systems. In this case, most of the investigations have been done experimentally, and the analytical models available are not sufficiently accurate. In this paper, the modeling of the sound transmission through a vehicle door seal is presented. The study is an extension of a previous work in which the applicability of the Hybrid FE-SEA method was demonstrated for predicting the TL of sealing elements.

During the last decades, the application of noise control treatments in vehicles has targeted the main noise transmission paths to interior noise. These paths include vehicle body panels such as dash panel, doors and floor. Many improvements have been achieved on these areas, and, as a consequence, other transmission paths once thought as secondary became relevant. This is the case of the sound transmission through door seals and others sealing elements at mid and high frequencies. In this paper, the interest lies on the prediction of the transmission loss of door seals. A full nonlinear deformation/contact analysis is used to estimate the deformed geometry of a door seal in real conditions. The geometry is then used in a vibro-acoustic analysis to predict the in-situ transmission loss of the seal using a local Hybrid FE-SEA model. The channel between the door and the car structure where the seal is located is also included in the analysis.