The controlled rotation of solid particles trapped in a liquid by an ultrasonic vortex beam is observed. Single polystyrene beads, or clusters, can be trapped against gravity while simultaneously rotated. The induced rotation of a single particle is compared to a torque balance model accounting for the acoustic response of the particle. The measured torque (∼ 10 pNm for a driving acoustic power...

As excess water is discharged from a high dam, low frequency noise (air pulsation lower than 10 Hz, LFN) is generated and propagated in the surrounding areas, causing environmental hazards such as the vibration of windows and doors and the discomfort of local residents. To study the generation mechanisms and key influencing factors of LFN induced by flood discharge and energy dissipation from a...

Thermo-elastic damping is a significant dissipation mechanism in high quality factor microstructures. In this paper, thermo-elastic damping of the in-plane vibration of fully clamped rectangular micro-plates has been studied. The governing equation of the micro-plate motion and heat conduction equation were derived. Then, The Galerkin method has been used to solve the coupled heat-displacement ...

Continuous carbon fiber composites with enhanced mechanical energy dissipation (vibration damping) under flexure are provided by incorporation of fillers between the laminae. Exfoliated graphite (EG) as a sole filler is more effective than carbon nanotube (SWCNT/ MWCNT), halloysite nanotube (HNT), or nanoclay as sole fillers in enhancing the loss tangent, if the curing pressure is 2.0 (not 0.5)...

The Hilbert Transform (HT) and its properties, applied to the analysis of linear and non-linear vibrations, are discussed at great length in [1]. The application of the HT to a signal provides some additional information about amplitude, instantaneous phase and vibration frequency. This information is valid when applied to the analysis of non-linear vibration motions [2]. Moreover, it has been ...