Simulation Of Flow Field Characteristic Of Non-Planar Porous Fences And Mechanical Analysis Of Supporting Structures

Dust pollution contributes to a great portion of as well as one of main causes to air pollution in China. As for the method to control dust in a large open stock piles, the porous fences technology is comparatively effective, and is the control technology and device of dust re-entrainment which is suitable for China.The paper mainly studies on butterfly and sand-interception porous fences, to research the influence of setting different parameters to the characteristics of flow field in the sheltering place behind butterfly and sand-interception porous fences by wind tunnel experiment device, and to provide reliable experiment data for optimal design of porous fence's structure. What is more, the paper makes force analysis and results verification for two kinds of steel framework applied to projects by the project group. The results of the study are significant to optimize the design and guarantee safety operation for the dust control engineering equipment of porous fences.Firstly, generally review the current state and development of porous fences with consideration of on-site test, numerical simulation and experimental research at home and abroad. And briefly introduce several representative dust control engineering of porous fences.Secondly, establish a wind tunnel experiment platform, conduct experimental study on the influence of setting different parameters to the characteristics of flow field in the sheltering place behind planar,butterfly and sand-interception porous fences in different working conditions. And the conclusions are as follows:â‘ Different types of porous fences have different optimal porosity. The best porosity is 26.4% for planar porous fences, with wind reduction rate 68.44%; Butterfly porous fences for 27.3%, with wind reduction rate 63.39%; the shelter will be most effective as the porosity of sand-interception porous fences is 27.1%, with wind reduction rate 63.01%.â‘¡As three types of porous fences have similar porosity, butterfly and sand-interception porous fences'shelter effect is a little lower than planar porous fences', but their intensity is much larger than planar porous fences', which are suitable to be used in engineering construction and promotion.â‘¢As the wind speed is 3m/s, butterfly porous fences with different hole diameters will have the best shelter effect to wake zone; the shelter effect will be reduced sequentially with the wind speed of 5, 7.5 and 10m/s.â‘£Planar and butterfly porous fences, with porosity of 26.4% and 27.3%, will have the biggest wind reduction rate of 68.81% and 66.84% respectively as their bottom gap is 0.15H. Under the same condition, they are respectively higher than wind reduction rates of 68.44% and 63.39%of planar and butterfly porous fences as both of them have no bottom gap.Finally, make force analysis for both upright-parallel and upright-oblique supporting steel framework by finite element analysis software, as well as have results verification. The conclusions show that both two kinds of steel framework meet the requirements of intensity, rigidity and stability. After the comparison is made between two kinds of steel framework, the structure of upright-oblique supporting steel framework is more reasonable.