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Analysis of wind-blown sand movement over transverse dunes.

Jiang H, Huang N, Zhu Y - Sci Rep (2014)

Bottom Line: Wind-blown sand movement often occurs in a very complicated desert environment where sand dunes and ripples are the basic forms.In fact, the windward slope gradient plays a great role in the lift-off and sand particle saltation.This study is a preliminary study on windblown sand movement in a complex terrain, and is of significance in the control of dust storms and land desertification.

View Article: PubMed Central - PubMed

Affiliation: 1] Key Laboratory of Mechanics on Disaster and Environment in Western China, Lanzhou University, Lanzhou 730000, China [2] Laboratoire de Mécanique des Fluides et d'Acoustique, Ecole Centrale de Lyon, Ecully 69130, France.

ABSTRACT
Wind-blown sand movement often occurs in a very complicated desert environment where sand dunes and ripples are the basic forms. However, most current studies on the theoretic and numerical models of wind-blown sand movement only consider ideal conditions such as steady wind velocity, flat sand surface, etc. In fact, the windward slope gradient plays a great role in the lift-off and sand particle saltation. In this paper, we propose a numerical model for the coupling effect between wind flow and saltating sand particles to simulate wind-blown sand movement over the slope surface and use the SIMPLE algorithm to calculate wind flow and simulate sands transport by tracking sand particle trajectories. We furthermore compare the result of numerical simulation with wind tunnel experiments. These results prove that sand particles have obvious effect on wind flow, especially that over the leeward slope. This study is a preliminary study on windblown sand movement in a complex terrain, and is of significance in the control of dust storms and land desertification.

No MeSH data available.


Related in: MedlinePlus

Simulated pure horizontal wind field.
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f7: Simulated pure horizontal wind field.

Mentions: Figure 5 and Figure 6 present the horizontal and vertical wind field velocity over transverse dune observed by PDPA for u* = 0.5 m/s where Hs is 0.05 m. Figure 7 and Figure 8 present the simulated the horizontal and vertical wind velocity profiles of u* = 0.5 m/s for a pure wind field. The wind flow field over the transverse dune has higher velocities and complex flow structure. It can be seen that the horizontal wind accelerated over the windward slope. There is a reversed flow region in lee side. Both the numerical simulation results and experimental measurement results show uniformly varying patterns in regard to the wind velocity profiles at discrete positions over the dune.


Analysis of wind-blown sand movement over transverse dunes.

Jiang H, Huang N, Zhu Y - Sci Rep (2014)

Simulated pure horizontal wind field.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4248282&req=5

f7: Simulated pure horizontal wind field.
Mentions: Figure 5 and Figure 6 present the horizontal and vertical wind field velocity over transverse dune observed by PDPA for u* = 0.5 m/s where Hs is 0.05 m. Figure 7 and Figure 8 present the simulated the horizontal and vertical wind velocity profiles of u* = 0.5 m/s for a pure wind field. The wind flow field over the transverse dune has higher velocities and complex flow structure. It can be seen that the horizontal wind accelerated over the windward slope. There is a reversed flow region in lee side. Both the numerical simulation results and experimental measurement results show uniformly varying patterns in regard to the wind velocity profiles at discrete positions over the dune.

Bottom Line: Wind-blown sand movement often occurs in a very complicated desert environment where sand dunes and ripples are the basic forms.In fact, the windward slope gradient plays a great role in the lift-off and sand particle saltation.This study is a preliminary study on windblown sand movement in a complex terrain, and is of significance in the control of dust storms and land desertification.

View Article: PubMed Central - PubMed

Affiliation: 1] Key Laboratory of Mechanics on Disaster and Environment in Western China, Lanzhou University, Lanzhou 730000, China [2] Laboratoire de Mécanique des Fluides et d'Acoustique, Ecole Centrale de Lyon, Ecully 69130, France.

ABSTRACT
Wind-blown sand movement often occurs in a very complicated desert environment where sand dunes and ripples are the basic forms. However, most current studies on the theoretic and numerical models of wind-blown sand movement only consider ideal conditions such as steady wind velocity, flat sand surface, etc. In fact, the windward slope gradient plays a great role in the lift-off and sand particle saltation. In this paper, we propose a numerical model for the coupling effect between wind flow and saltating sand particles to simulate wind-blown sand movement over the slope surface and use the SIMPLE algorithm to calculate wind flow and simulate sands transport by tracking sand particle trajectories. We furthermore compare the result of numerical simulation with wind tunnel experiments. These results prove that sand particles have obvious effect on wind flow, especially that over the leeward slope. This study is a preliminary study on windblown sand movement in a complex terrain, and is of significance in the control of dust storms and land desertification.

No MeSH data available.


Related in: MedlinePlus