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| Numerical Simulation of Saltation on the Windward Side of Sand Dunes |
| Wu Shengzhi, Guo Weijin |
| Ministry of Education Key Laboratory of Mechanics on Disaster and Environment in Western China/School of Civil Engineering and Mechanics, Lanzhou University, Lanzhou 730000, China |
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Abstract A new model is presented for calculating sand saltation on the windward side of two-dimensional dune. First, the wind profile is established by using the wind engineering and aerodynamics achievements, then the saltation of sand grains in a turbulent air flow is simulated by employing particle trajectory method. Since the wind field on the dune is quite complicated, and the wind profiles are different along the windward side of the dune, some typical positions are selected for numerical simulation. The surface ejection flux as initial condition in calculation is obtained by field measurement or empirical relationship with local friction velocity in literature. The numerical results show that the mean wind speed increases from the foot to the top of dune and reaches its maximum speed-up ratio at the dune top, the simulated sand transport rate and the mass flux profile are in good accordance with results reported in literature.
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Received: 22 January 2013
Published: 20 March 2014
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2014, Vol. 34 
