Research of Acoustic Metamaterials at the University of Szeged …
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Fig. 14 Amplitude ratio
A n /A 1 in function of angular
frequency ratio ω g /ω 1
Fig. 15 Phase shifts
between displacements d n
and d 1 in function of ω g /ω 1
the half of ω 1 appears a new natural angular frequency, which is the resultant natural
angular frequency ω R of the five masses. The value of ω R may be set with proper
selection of the parameters of the model. If theexcitation is not typically occurs in
the lower range of ω 1 , these parameters can operate well. The phase shift between
the excitation force and the displacement of mass m 1 is presented on Fig. 17.
There is an interesting question, what can be made with the energy of vibration
that is captured by the wall-paper. The simplest answer is: let it diffuse in the form
of heat into the surroundings. But there is a possibility to use it to useful purposes.
For example if a piezo-electric quartz may be attached to the masses, which would
generate electric current it could be a supplier of an electrical instrument or stored
in accumulator.