Kotinda G., Steffen Jr. V., Rade D.

In the context of passive noise and vibration control, passive dynamic vibration absorbers (DVAs) have been regarded as an interesting strategy, mainly due to their simplicity, operational efficiency, flexibility of design and cost-effectiveness. However, one of the main disadvantages of those devices is that their operational frequency band is relatively narrow, which means that they are prone to loose their effectiveness in case the excitation frequency changes with respect to the nominal value used in the DVA design. To cope with this shortcoming, one alternative is to use multiple DVAs, in such a way that the arrangement is conceived as a series of individual DVAs, each of one tuned to a frequency value within the frequency band of interest. This strategy is focused in this paper. A particular configuration of beam-like multimodal DVA is considered. For the DVA design, accounting for constraints, an optimization strategy based on Ant Colony heuristics is adopted. The performance and operational features of the DVA, in terms of attenuation of harmonic vibrations, are evaluated by means of finite element simulations and experimental tests in which the device is applied to rectangular plates.