Modelling of vibration damping in pneumatic tyres: Appropriate interpretation of complex modes

摘要

Taking the pneumatic tyre as an example, this paper presents a detailed investigation into the appropriaterninterpretation of vibration modes in complex structures, aiming at an in-depth understanding as well asrnproper modelling of damping properties. Through an elaborately designed modal testing, the commonlyrnapplied real modal interpretation is extended into a more general form. Based upon this approach, the 1strnorder state-space complex modal interpretation with general viscous damping assumption is discussed.rnEnhanced derivations are made to the appropriate normalization of complex modes and its physicalrnexplanation. Furthermore, the 2nd order Rayleigh’s small-damping approximation is introduced into therngeneral expression of the complex modes in order to investigate its suitablity for the complex moderninterpretation under general viscous or non-viscous damping assumptions. On the basis of experimentalrnresults, comparisons are made between the real modal and complex modal interpretations.