Spontaneous jamming and unjamming in a hopper with multiple exit orifices

Kunte, Amit; Doshi, Pankaj; Orpe, Ashish V.

doi:10.1103/physreve.90.020201

Cited by 29 publications

(19 citation statements)

References 23 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…6(a)] for all combinations of w and µ, except one or two cases. The exponential behavior is typical of the random nature of discrete avalanche events and is in accordance with the behavior observed previously for single [7,11] as well as multiorifice [8] silos. The occurrence of jamming, thus, is not necessarily influenced by the presence of independent forcing in the form of fluctuations originating from the second orifice in the system.…”

Section: Resultssupporting

confidence: 91%

“…The DEM simulations methodology employed and the system geometry is nearly identical to that used in previous work [8,18] and we provide only relevant details over here. The simulations, carried out using the Large Atomic/Molecular Massively Parallel Simulator (LAMMPS), employ a Hookean force between two contacting particles which consists of a normal component (F n ) and a tangential component (F t ).…”

Section: Methodsmentioning

confidence: 99%

“…The continual presence of such an independent parallel forcing results in an intermittent flow through the orifice (flow followed by jamming followed by flow and so on), which can vary from a continuous flow regime to a permanently jammed regime dependent on the propensity of the forcing, i.e., vibration intensity [7] or the distance between two orifices [8]. Within the intermittent flow regime, the distribution of the times during which orifice is flowing exhibits an exponential tail, while those corresponding to jammed state exhibits a power-law tail [7].…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Friction-mediated flow and jamming in a two-dimensional silo with two exit orifices

Orpe

Doshi

2019

Phys. Rev. E

Self Cite

View full text Add to dashboard Cite

We show that the interparticle friction coefficient significantly influences the flow and jamming behavior of granular materials exiting through the orifice of a two-dimensional silo in the presence of another orifice located in its vicinity. The fluctuations emanating from a continuous flow through a larger orifice results in an intermittent flow through the smaller orifice consisting of sequential jamming and flowing events. The mean time duration of jammed and flow events, respectively, increase and decrease monotonically with increasing interparticle friction coefficient. The frequency of unjamming instances (nu), however, shows a nonmonotonic behavior comprising an increase followed by a decrease with increasing friction coefficient. The decrease on either side of the maximum, then, represents a system moving progressively towards a permanently jammed or a permanently flowing state. The overall behavior shows a systematic dependence on the interorifice distance which determines the strength of the fluctuations reaching the smaller orifice leading to unjamming instances. The probability distributions of jamming and flowing times are nearly similar for different combinations of friction coefficients and interorifice distances studied and, respectively, exhibit exponential and power-law tails.

show abstract

Section: Resultssupporting

confidence: 91%

Section: Methodsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Friction-mediated flow and jamming in a two-dimensional silo with two exit orifices

Orpe

Doshi

2019

Phys. Rev. E

Self Cite

View full text Add to dashboard Cite

show abstract

“…The intruder acts as a boundary between the inner and outer ring, creating two effective apertures. Our system is thus related to a highly coupled twoaperture clogging system [25], which is less well understood than the single-aperture case [22][23][24]. Our system sticks (or clogs) more often than expected for a single aperture of a size equivalent to the width of one of our two "effective apertures," which are each approximately 6 large particle diameters across.…”

Section: Discussionmentioning

confidence: 94%

Dynamics of a grain-scale intruder in a two-dimensional granular medium with and without basal friction

et al. 2019

View full text Add to dashboard Cite

We report on a series of experiments in which a grain-sized intruder is pulled by a spring through a 2D granular material comprised of photoelastic disks in a Couette geometry. We study the intruder dynamics as a function of packing fraction for two types of supporting substrates: a frictional glass plate and a layer of water for which basal friction forces are negligible. We observe two dynamical regimes: intermittent flow, in which the intruder moves freely most of the time but occasionally gets stuck, and stick-slip dynamics, in which the intruder advances via a sequence of distinct, rapid events. When basal friction is present, we observe a smooth crossover between the two regimes as a function of packing fraction, and we find that reducing the interparticle friction coefficient causes the stick-slip regime to shift to higher packing fractions. When basal friction is eliminated, we observe intermittent flow at all accessible packing fractions. For all cases, we present results for the statistics of stick events, the intruder velocity, and the force exerted on the intruder by the grains. Our results indicate the qualitative importance of basal friction at high packing fractions and suggest a possible connection between intruder dynamics in a static material and clogging dynamics in granular flows.

show abstract

“…This results show that the destabilization near an intruder propagates toward the other site and may trigger an event if they are close enough. This situation is similar to the case of the silo with multiple orifices, where the flow through one outlet may unjam the flow of the second outlet [23].…”

Section: Characteristic Lengthsmentioning

confidence: 89%

Transformation around intruders in granular media

2017

View full text Add to dashboard Cite

Abstract. Sintering, glass melting and other industrially relevant processes turn batches of grains into homogeneous products. Such processes involve coupled chemical and physical transformations of the granular packing. For sake of simplicity, we study how local evolutions on grains (volume decreases for example) entail mechanical rearrangements in the overall pile. Inert bidisperse metallic disks are mixed and confined in a vertical 2D cell. At the bottom of this set-up, initial intruders (one or two) have been previously set and mechanically linked to a linear motorized jack. While we quasi-statically pull the intruder(s) downward out of the cell at constant speed and constant liberated surface, we tracked the surrounding granular packing. Events largely distributed both spatially and temporally occur around intruders. We focus on the influence of the distance between the intruders on the local dynamic of the packing. We compare the distribution of the size of the event and their frequency as function of the relative position of the intruder, as a function of their radius. We show that their influence decreases rapidly. At short distance the mechanical perturbation induced by one intruder can destabilize the packing around the other.

show abstract

Spontaneous jamming and unjamming in a hopper with multiple exit orifices

Cited by 29 publications

References 23 publications

Friction-mediated flow and jamming in a two-dimensional silo with two exit orifices

Friction-mediated flow and jamming in a two-dimensional silo with two exit orifices

Dynamics of a grain-scale intruder in a two-dimensional granular medium with and without basal friction

Transformation around intruders in granular media

Contact Info

Product

Resources

About