Evaluation of Granular-Fill Damping In a Shock-Loaded Box Beam
نویسندگان
چکیده
The experimental evaluation of damping performance in a granular-material-filled box beam is presented. The study determined that granular-fill provided significant damping for a high impact excited free-free box beam. A large modal loss factor, exceeding 0.15, was obtained for the few lowest bending modes of the beam. The damping was effective over the frequency range 40 300 Hz. A variety of data analyses and modeling methods were used to assess the damping effects from acceleration data. These methods included a novel "complex wave number method'' in which the damping values were determined for different wave types over discrete, but regularly-spaced, frequency values. These results were compared with conventional methods such as a modal analysis approach.
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