Computational Model to Investigate the Sound Radiation from Rolling Tires

Abstract

Abstract Tire/road noise is one of the most urgent problems in traffic noise abatement. Therefore, to facilitate the design process of low noise tire/road systems, the development of appropriate computational tools, accounting for the most relevant effects of the noise generation and radiation, seems essential. However, until now no physically based and validated models exist that can be used to determine the sound radiation of rolling vehicle tires within the relevant frequency range and with reasonable accuracy. The numerical model presented here is based on a simulation process that may be split into several analysis steps: computation of the nonlinear stationary rolling process, analysis of the tire dynamics caused by the road roughness, and computation of the sound radiation. This contribution is concerned with the latter part of the analysis procedure. For the sound radiation analysis, the vibrations on the tire surface are extracted from a preceding structural analysis and used as boundary conditions in the acoustic model. The acoustic simulation process is based on the finite/infinite element approach, where an improved variant of the so-called Astley-Leis elements is used to model the sound radiation. The efficiency of the employed numerical methods is somewhat essential, because computational costs generally restrict the frequency range which can be simulated. By evaluating the sound pressure field, it is possible to compare the acoustic performance of specific tire/road systems, and the influence of certain parameters, such as the road texture or the impedance, on the noise radiation can be studied. The current work focuses on the validation of the computational model. Hence, characteristic results from the numerical simulations are compared with corresponding measurement data obtained from different test setups, including standing as well as rolling tires. This paper is dedicated to Em. O. Univ. Professor Dipl.-Ing. Dr. Techn. Dr. H. C. Franz Ziegler on the occasion of his 70th birthday.