# Modelling segregation of bidisperse granular mixtures varying simultaneously in size and density for free surface flows

@article{Duan2021ModellingSO, title={Modelling segregation of bidisperse granular mixtures varying simultaneously in size and density for free surface flows}, author={Yifei Duan and Paul B. Umbanhowar and Julio M. Ottino and Richard M. Lueptow}, journal={Journal of Fluid Mechanics}, year={2021}, volume={918} }

Abstract Flowing granular materials segregate due to differences in particle size (driven by percolation) and density (driven by buoyancy). Modelling the segregation of mixtures of large/heavy particles and small/light particles is challenging due to the opposing effects of the two segregation mechanisms. Using discrete element method (DEM) simulations of combined size and density segregation we show that the segregation velocity is well described by a model that depends linearly on the local…

## 6 Citations

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

- GeologyJournal of Geophysical Research: Solid Earth
- 2021

Size segregation is a common feature in geophysical mass flow deposits and is an active process during motion. The presence of interstitial fluids in such flows affect the motion of constituent…

A unified description of gravity- and kinematics-induced segregation forces in dense granular flows

- PhysicsJournal of Fluid Mechanics
- 2021

Abstract Particle segregation is common in natural and industrial processes involving flowing granular materials. Complex, and seemingly contradictory, segregation phenomena have been observed for…

Segregation forces in dense granular flows: closing the gap between single intruders and mixtures

- BiologyJournal of Fluid Mechanics
- 2022

A semiempirical model for the segregation force in size-bidisperse sphere mixtures is developed that predicts the concentration below which the single-intruder assumption applies and provides an accurate description of the pressure partitioning between species.

Mild stratification in drying films of colloidal mixtures.

- Environmental ScienceSoft matter
- 2022

Size stratification of bidisperse colloidal mixtures during vertical drying was investigated using the implicit solvent Langevin dynamics (LD) simulation and the explicit solvent lattice Boltzmann…

Predicting segregation of nonspherical particles

- Physics
- 2021

Most natural and industrial flows involve mixtures of nonspherical particle species. A general approach to predicting segregation over the infinite space of all possible particle shapes and sizes…

Lift force acting on an intruder in dense, granular shear flows

- EngineeringPhysical Review E
- 2021

We report a new lift force model for intruders in dense, granular shear flows. Our derivation is based on the thermal buoyancy model of Trujillo & Hermann[L. Trujillo and H. J. Herrmann, Physica A…

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