Granular impedance and its role in energy transfer in vibro-fluidized low-friction granular materials

Impedance, a concept commonly applied to electrical circuits and simple mechanical systems, is seldom used in the context of multibody mechanical systems undergoing forced vibration. This study explored the impedance characteristics of vibro-fluidized low-friction granular materials experimentally. Owing to the consumption, storage, and release of mechanical energy by vibrated particles, the notions of granular resistance and granular capacitance were introduced. It was found that at certain vibration intensities, both granular resistance and capacitance remain constant, yet their reactions to vibration frequencies differ. Granular circuits were created to illustrate energy transfer among particles, with frequency-band division providing a basis for discussion. It was also found that in specific granular circuits, maximum and zero granular resistances exist. To explain granular impedance variations in relation to vibration, the freedom and synchrony of granular motion were considered. These findings offer novel insight into the energy transfer mechanisms within vibrated granular materials. [Display omitted] •Impedance concept was introduced in vibro-fluidized granular materials.•Granular impedance has invariant regions and unique frequency responses.•Energy transfer was illustrated by granular circuits in three frequency bands.•Maximum and zero granular resistances exist under certain vibrations.•Freedom and synchrony of granular motion were used to explain the results.