Numerical Simulation Research On The Sand Saltation Trajectory

Grasp the movement rule of single grain of sand movement in the field of macro research has positive significance. Firstly, from the start of the movement in the form of sand, the starting mechanisms of sand and sand grains in the process of saltation force are analyzed. With the aid of Fluent CFD software. Choose the standard-anodel as turbulence model salutation sand to simulate the trajectories.In full consideration of the force based on the sand, to simulate the same friction wind speed, different sand particle size under the condition of considering turbulent fluctuation and does not consider gas turbulent flow pulsation of sand salutation trajectory. And the same particle size sand, different friction velocity of sand trajectory salutation. Through analysis and comparison obtain the following conclusions:When the sand particle size within the range of500um-200um, sand salutation trajectory is not affected by turbulent fluctuations of gas; At the same friction velocity, with decreasing size of the sand, the role of gas turbulent fluctuation is becoming increasingly apparent; Sand salutation distance and height ratio decreases with increasing particle size. When the sand particle size≤160um, its motion curve has a convex segment in decline trend, the curve is no longer smooth, but still keep salutation state, in which case it will have to consider the impact of turbulent fluctuation effects.By means of indoor wind tunnel for sand saltation trajectory for high-speed photography experiments, numerical simulation have been approximately the same parabolic trajectory, which verifies the reliability of the numerical simulation.