Abstract: An approach to a wide-band frequency passive vibration attenuation
is introduced in this paper. This aims to suppress noise and vibration of
extended multimode objects like plates, panels and shells. The absorber is
arranged in the form of a single-layer assembly of small inertial bodies
(balls) being distributed and moulded within the light visco-elastic media
(e.g. silicone resin). The absorber as a whole is embedded into object face
covering the critical patches of the system surface. For the purpose of
characterization, the authors introduced the complex frequency response
function relating the volume velocity produced by the vibrating object surface
(response) stimulated by a point-wise force (stimulus) applied to a particular
point. The simulation and optimization of the main frequency characteristics
has been performed using a full scale 3-dimensional Finite Element model. These
revealed some new dynamic features of absorber's structures, which can
contribute to vibration attenuation. A full-scale physical experimentation with
synthesised absorber's structures confirmed the main results of simulation and
has shown significant noise reduction over a staggering 0–20 kHz
frequency band. This was achieved with a negligible weight and volume penalty
due to the addition of the absorber. The results can find multiple applications
in noise and vibration control of different structures. Some examples of such
applications are presented.
Keywords: Noise and vibration control, passive vibration attenuation, wide frequency band absorber
