This paper has considered the vibration modelling of a tyre sidewall, represented as an anisotropic membrane with spatially varying material properties. Crucial to the dynamical behaviour is the mean stress state associated with pressurisation. A Finite-Element analysis shows that this state is dominated by the meridional tension component, with its azimuthal counterpart negligible in comparison. The membrane tensions thus differ significantly both from the classical solution for a toroidal surface, and from a one-dimensional approximation that neglects azimuthal variations. The pressurised geometry appears close to toroidal when plotted, but exhibits notable departures in its curvature components. A preliminary assessment of the dynamical behaviour has been made on the basis of the fixed-edge modes. These fall into two classes, with predominantly azimuthal and predominantly cross-sectional displacements respectively. The latter can also be analysed via the one-dimensional approximation. For the cases tested uniform thickness, representative thickness variation, and uniform thickness with dynamic stiffening the one-dimensional analysis (with spatially uniform properties) gives results very similar to those of the full model. Further investigations into how these observations translate to the impedance presented to the belt by the side-wall, and into the effects of rotation, will be included in the oral presentation.
Modelling tyre sidewall dynamics
Modellierung der Reifenseitenwanddynamik
2012
14 Seiten, 9 Bilder, 5 Tabellen, 10 Quellen
Conference paper
English