Experimental investigation of the concentration profile of a blowing sand cloud

Li, Xiaoping; Dong, Zhibao

doi:10.1016/j.geomorph.2003.08.009

Cited by 68 publications

(58 citation statements)

References 23 publications

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“…Instead, the particles are only kept alive in the saltation layer by bed-particle collisions and momentum transfer from the air stream to the particles. In any case, the saltation layer represents a dilute regime where the maximum volume fraction is around 5.10 -4 [2], indicating that the particles in saltation contribute only to the kinetic contribution to the solids viscosity and not the collisional regime like Jenkins and Hanes [8] and Jenkins and Pasini [1] suggest.…”

Section: Cfd Models and Granular Kinetic Theorymentioning

confidence: 93%

“…The geometry chosen for the simulation matches the experimental setup and results obtained by Liu and Dong [2], which were made in a saltation wind tunnel with a total length of 37.78m and a working cross-section of 0.8m x 1m. A twodimensional channel with dimensions L x x L y was used for representing the computational domain.…”

Section: Geometry Grid Boundary Conditions and Initial Conditionsmentioning

confidence: 99%

“…Equation (30) shows the logarithmical air profile used in the simulation inlet boundary velocity, which was fitted based on air-wind profile data, without sand transport, presented by Liu and Dong [2]. The logarithmical air profile begins just over the sand bed and finishes in the limit of the boundary layer.…”

Section: Geometry Grid Boundary Conditions and Initial Conditionsmentioning

confidence: 99%

“…The saturation mass flux used to do the dimensionless curves associated with the figure 6 was of 0.744 kg s -1 [2]. Figure 4 shows the sensitivity of the sand bed to the erosion according to the chosen frictional pressure model.…”

Section: Temporal Evolution Of Total Mass and Mass Fluxmentioning

confidence: 99%

“…The gas phase turbulence closure model is the standard k-ε model, and the solid-phase stress is described using GKT, with a frictional model which is applied for sustained particle contacts. The mathematical model is implemented in the commercial code ANSYS-Fluent and computed results are compared with experimental data given by [2] and the model predictions given by [ …”

Section: Introductionmentioning

confidence: 99%

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Two-Dimensional Numerical Simulation of Saltating Particles Using Granular Kinetic Theory

Marval

Rojas‐Solórzano

Curtis

2007

Volume 1: Symposia, Parts a and B

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Most granular flows at environmental conditions are unsteady and exhibit a complex physical behavior. Dune formation and migration in the desert are controlled not only by the flow of saltating particles over the sand bed, but also by turbulent atmospheric airflow. In fact, sediments are transported by the atmospheric airflow within a thin layer only a few centimeters above the sandy surface. These jumping particles reach a maximum sediment mass flux level at a certain delay time (known as the "saturation time") after the initial movement by sliding and rolling begins. Unlike sediment transport in water where the particles are lifted by the turbulent suspension, the saltating particles are kept alive in the layer mainly due to particle-particle and particle-bed collisions. In order to model this Aeolian transport of sand, Jenkins and Pasini [1] proposed a two-fluid model (one-dimensional and steady state) using Granular Kinetic Theory (GKT) to describe the solid-phase stress. The present work extends the original idea of Jenkins and Pasini [1] by using a more robust model of GKT for the kinetic/collisional contributions to the solid-phase stress tensor, together with a friction model activated for sustained contacts between particles. In addition, a standard k-ε turbulence model for the air and a drag model for the interaction between the phases are employed. A rectangular 2D geometry was chosen with a logarithmic profile for the inlet air velocity, along with an initial amount of sand at rest in the lower part of the simulation domain, resembling the particle saltating flow commonly seen in the vertical middle plane within saltation wind tunnels. This model is validated with experimental data from Liu and Dong [2] and the results given by Pasini and Jenkins [1]. A good estimation for the particle erosion and mass flux in the saltation layer is predicted, even though the profiles of mass flux and concentration within the transport layer are very thin and lower.

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Section: Cfd Models and Granular Kinetic Theorymentioning

confidence: 93%

Section: Geometry Grid Boundary Conditions and Initial Conditionsmentioning

confidence: 99%