Particle Movement Behaior And Force Analysis The Porous Fence With Deflectors

In this paper,the commercial software Fluent and wind tunnel experiments were used to analyze the dust suppression property and force analysis for different kinds of porous fence.And the discrete phase model was used to simulate movement behavior and force analysis of the particle after the deflector-porous fence.Research work is about analysis of stress and structure stability of the fence which based on field characteristics.The setting of the porous fence can not only reduce the wind speed on the sand surface,but also reduce the intensity of turbulent airflow on the sand surface.In this paper,the main research work is as follows:(1)Simulation analysis of the mechanical characteristic was compared between deflector-porous fence and traditional porous fence.The results show that the main reason of porous fence resistance is the different pressure before and after fence and the development of trailing vortex turbulence;and the wind-load increased with the wind speed,to present a quadratic growth.The wind-load growth about 20 times when wind speed increased from 3m·s-1 to 15m·s-1.Deflector-porous fence improves the dust suppression property without increasing the investment of structural support.(2)The Wind tunnel experiments was used to study camouflage effect of porous fences.Analyzing the results between experiment and simulation.Raising dust experiments about different sand drift were studied.The results show that raise dust occurs mainly on the windward side of the sand drift.There was serious particles rotate between porous fence and sand drift.No particles escape into the atmosphere,so screening effect of the deflector-porous fence is the best.The amount of raise dust of silver sand was 100 times of the coarse sand.The smaller the particle size,the lower quality ratio and higher number ratio.There was some deviation between experimental result and simulated result,so its necessary to do experimental of camouflage effect of porous fences.(3)Stochastic trajectory model was used to trace particle movement and analyze the particle force.The results show that distribution of flow field,density and size of the particles,and wind speed can affect the particle trajectories.Low density and small size particles are more easily affected by recirculation region.In particle movement the leading force was drag force and particles gravity.In the early stages of the particle takeoff,Saffman force plays an important role in the process of particles into the saltation layer,Magnus force is just 1%of the gravity.In the process of particle movement the total energy change trend was mainly determined by the kinetic energy.Vortex in the air flow will provide particles with higher energy into the atmosphere.