Segregation process of water-granular mixtures released down a steep chute

Zanuttigh, Barbara; Ghilardi, Paolo

doi:10.1016/j.jhydrol.2010.07.016

Cited by 12 publications

(9 citation statements)

References 14 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Modelling these waves could be a unique way to investigate rheological laws near the static-flowing transition. Furthermore, a challenging issue is to quantify the role of interstitial fluid and grain polydispersity on erosion/deposition and roll waves development to ultimately compare them with natural surges (e. g. Iverson and Denlinger (2001), Zanuttigh and Lamberti (2007), Zanuttigh and Ghilardi (2010)). Indeed, natural surges are strongly heterogeneous as they are generally composed of a first surge, mainly containing boulders, and of possible secondary waves that are generally muddier as shown in large scale experiments (see section 3.3 and Figure 7).…”

Section: Waves or Wave-like Avalanchesmentioning

confidence: 99%

Granular and particle-laden flows: from laboratory experiments to field observations

Delannay¹,

Valance²,

Mangeney³

et al. 2017

J. Phys. D: Appl. Phys.

196

141

View full text Add to dashboard Cite

This review article provides an overview of dry granular flows and particle fluid mixtures, including experimental and numerical modeling at the laboratory scale, large scale hydrodynamics approaches and field observations. Over the past ten years, the theoretical and numerical approaches have made such significant progress that they are capable of providing qualitative and quantitative estimates of particle concentration and particle velocity profiles in steady and fully developed particulate flows. The next step which is currently developed is the extension of these approaches to unsteady and inhomogeneous flow configurations relevant to most of geophysical flows. We also emphasize that the up-scaling from laboratory experiments to large scale geophysical flows still poses some theoretical physical challenges. For example, the reduction of the dissipation that is responsible for the unexpected long run-out of large scale granular avalanches is not observed at the laboratory scale and its physical origin is still a matter of debate. However, we believe that the theoretical approaches have reached a mature state and that it is now reasonable to tackle complex particulate flows that incorporate more and more degrees of complexity of natural flows. environments, landslides initiate on continental margins or on oceanic ridges, are assumed to be more or less coherent solid masses, and may be more voluminous than their subaerial equivalents (Hampton et al. (1996), Masson et al. (2006)). While submarine landslide activity is rarely observed, recent high resolution surveys of underwater depth of ocean floors reveals small to large landslide deposits that shape the morphology of medio-oceanic ridges (Cannat et al. (2013)). In contrast, turbidity currents are generally smaller flows with low particle volume fraction (Normack et al. (1993), Meiburg and Kneller (2010), Cantero et al. (2012)). Snow avalanches can be dry or wet and the distinction is made between dense slab avalanches, of moderate thickness and high particle concentration, and powder snow avalanches of larger thickness and much lower particle concentration (Hopfinger (1983), Ancey (2001), Schweizer et al. (2003)). Volcanoes generate hot mixtures of volcanic gas and particles, called pyroclastic density currents, through lateral explosion of a magma body or the gravitational collapse of a lava dome or of an eruptive column (Druitt (1998), Branney and Kokelaar (2002), Roche et al. (2013a), Dufek (2016)). Pyroclastic flows and surges represent the dense and dilute end-members of mechanisms, respectively, and often coexist as a dense underflow is commonly overridden by a dilute turbulent ash cloud. Debris flows are dense mixtures of water and solid particles generated in various subaerial environments on Earth and on other planets (Iverson (1997), Iverson et al. (1997), Zanuttigh and Lamberti (2007), Mangold et al. (2010)) and they can derive from landslides (Scott et al. 2001). Lahars are debris flows resulting from the mixing of pyroclastic material with water ...

show abstract

Section: Waves or Wave-like Avalanchesmentioning

confidence: 99%

Granular and particle-laden flows: from laboratory experiments to field observations

Delannay¹,

Valance²,

Mangeney³

et al. 2017

J. Phys. D: Appl. Phys.

196

141

View full text Add to dashboard Cite

show abstract

“…Real‐world granular flows, however, are either fluid‐laden or immersed in different viscous fluids, wherein solid‐fluid interactions significantly affect the particle motion (Ancey, 2007; Iverson, 1997) and hence result in complex segregation behaviors. Indeed, the extent in which inverse grading and other segregation related features can be observed in saturated geophysical flows vary depending on the mixture material properties (Major, 1997; Zanuttigh & Ghilardi, 2010; Zhou et al., 2019). Inverse grading of particle size species becomes less evident when the density of the fluid approaches the particle density and totally inhibits it when the fluid and the particles are isodense (Thornton et al., 2006).…”

Section: Introductionmentioning

confidence: 99%

Viscous Effects on the Particle Size Segregation in Geophysical Mass Flows: Insights From Immersed Granular Shear Flow Simulations

2021

View full text Add to dashboard Cite

show abstract

“…However, real-world granular flows are water-laden (i.e., debris flows and mud flows) or are completely submerged (i.e., submarine landslides and sediment flows), where solid-fluid interactions become significant and actively influence the particle dynamics and subsequent rearrangement (Coussot & Meunier, 1996;Iverson, 1997). In such cases, segregation is not as evident or is weaker, relative to dry flows, depending on various factors such as saturation (Major, 1997;Zhou et al, 2019), grain-sized distribution (Zanuttigh & Ghilardi, 2010), and fluid properties (Vallance & Savage, 2000). Although dry granular segregation has already been extensively studied, the role of fluids in this process remains unclear.…”

Section: Introductionmentioning

confidence: 99%

Particle Size Segregation in Granular Mass Flows With Different Ambient Fluids

et al. 2020

View full text Add to dashboard Cite

Size segregation, which is a robust feature of sheared granular mixtures and geophysical mass flow deposits, is found to diminish in the presence of a viscous fluid. We study this inhibitive effect through coupled fluid-particle simulations of granular flows fully immersed in different ambient fluids. Granular-fluid mixture flows are modeled according to three distinct flow regimes-free fall, fluid inertial, and viscous-at different angles of inclination. Each flow regime corresponds to distinct flow dynamics and segregation behaviors. We find that segregation is indeed weaker and slower in the presence of an ambient fluid, which is more so as the flow becomes more viscous. The ambient fluid affects segregation in two major ways. First, buoyancy reduces the contact pressure gradients which are needed to drive large particles up, while at the same time reduces the particles' apparent weight. On the other hand, the streamwise drag force substantially changes the flow rheology, specifically the shear rate profile, thereby modifying the segregation behavior in the normal direction. Surprisingly, the fluid drag in the normal direction is negligible regardless of the fluid viscosity and does not affect segregation in a direct manner.

show abstract

Segregation process of water-granular mixtures released down a steep chute

Cited by 12 publications

References 14 publications

Granular and particle-laden flows: from laboratory experiments to field observations

Granular and particle-laden flows: from laboratory experiments to field observations

Viscous Effects on the Particle Size Segregation in Geophysical Mass Flows: Insights From Immersed Granular Shear Flow Simulations

Particle Size Segregation in Granular Mass Flows With Different Ambient Fluids

Contact Info

Product

Resources

About