Polymers are materials, widely used for reduction and control of structural vibration. When designing vibration isolation elements with polymers it is desirable to have frequency dependent material functions in analytical form in order to predict structural response. Generalized rheological models and fractional derivative models (FDM) are the most used approaches to the analytical modeling. Accuracy of predicted structural response depends on accuracy of analytical characterization of polymer.
In this thesis accuracy of both models was checked in case of thermoplastic polyurethane. Dynamic material properties were determined with oscillatory tests. On the basis of these properties, transmissibility was analytically predicted, which was compared to transmissibility experiment and to transmissibility analytically determined on basis of dynamic material properties, modeled with generalized Maxwel model and 4-parametric FDM model.
It was discovered that prediction of transmissibility on basis of known dynamic material functions is appropriate to assess maximal value of transmissibility and correspondent excitation frequency. Relative error of maximal value of transmissibility equals to 0,342 and relative error of correspondent frequency equals to 0,185. It was also discovered that the values of maximal transmissibility and correspondent frequency are very dependent on analytical modeling approach.
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