Effect of Earth Surface Temperature on Saltation Trajectories of Sand particles
Zheng Xiaojing,Yue Gaowei
(Department of mechanics,Lanzhou University,Lanzhou 730000)

Abstract: The saltation trajectories of sand particles in a horizontal wind field and a vertical wind field arising due to solar radiation are investigated to find out the influence of the temperature variation near the earth surface on the saltation movement of sand particles. Calculated the temperature near the earth surface and the upward wind speeds at different moments during a full day, the saltation trajectories of sand particles in a horizontal wind field combined with the vertical wind field are simulated. The numerical results show that the maximum height and span of the trajectories respectively increase by 55.56% and 73. 68% afternoon at which the upward wind speed approaches to 1.5m/s. Moreover, when the upward wind speed is taken into account, the calculated trajectories of sand particles with individual diameters are different, which is quite distinguished from the simulation without upward wind speed.
Keywords: wind-blown sand movement, saltation trajectory, solar radiation, temp erature variation, simulation.