Physics – Condensed Matter
Scientific paper
2000-06-21
Physics
Condensed Matter
Final version to appear in PRE
Scientific paper
10.1103/PhysRevE.64.011306
The quasi-static frequency response of a granular medium is measured by a forced torsion oscillator method, with forcing frequency $f_{p}$ in the range $10^{-4}$ Hz to 5 Hz, while weak vibrations at high-frequency $f_{s}$, in the range 50 Hz to 200 Hz, are generated by an external shaker. The intensity of vibration, $\Gamma $, is below the fluidization limit. A loss factor peak is observed in the oscillator response as a function of $\Gamma $ or $f_{p}$. In a plot of $\ln f_{p}$ against $1/\Gamma $, the position of the peak follows an Arrhenius-like behaviour over four orders of magnitude in $f_{p}$. The data can be described as a stochastic hopping process involving a probability factor $\exp(-\Gamma_{j}/\Gamma)$ with $\Gamma_{j}$ a $f_{s}$-dependent characteristic vibration intensity. A $f_{s}$-independent description is given by $\exp(-\tau_{j}/\tau)$, with $\tau_{j}$ an intrinsic characteristic time, and $\tau =\Gamma ^{n}/2\pi f_{s}$, n=0.5-0.6, an empirical control parameter with unit of time. $\tau$ is seen as the effective average time during which the perturbed grains can undergo structural rearrangement. The loss factor peak appears as a crossover in the dynamic behaviour of the vibrated granular system, which, at the time-scale $ 1/f_{p}$, is solid-like at low $\Gamma$, and the oscillator is jammed into the granular material, and is fluid-like at high $\Gamma$, where the oscillator can slide viscously.
D'Anna G.
Gremaud G.
No associations
LandOfFree
Vibration-induced "thermally activated" jamming transition in granular media does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Vibration-induced "thermally activated" jamming transition in granular media, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Vibration-induced "thermally activated" jamming transition in granular media will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-22709