| Porous fence has been widely used to reduce dust pollution in industry. The basic unitof porous fence is porous plate. Porous fence has many different ways of dispositionwhile the porous plate also has a large range of possible geometric shape. The mainpurpose of this thesis is to give some suggestions on improving the shelter effect ofporous fence. The research is all through numerical simulation with computers. Theaerodynamic characteristics of single-layer butterfly-shaped porous plates withdifferent geometrical parameters, two kinds of sandwich porous plates, as well as anarc-section-shape porous plate, and the gas-solid flow, including gas flowingcondition and solid particles movements, around porous fence models with andwithout coal piles, are studied. The final conclusions includes, the butterfly shapeporous plate has a best performance when its folding angle is 45°, b value is 200mm,and with a equal porosity, shelter effect of porous fence is weak under low windvelocity while circumfluence behind the fence will become strong when wind velocityis high, when height porous fence is increased to a certain value the flow andmovement of coal particles after fence at the bottom will become to a certainty steady,the eddy behind the fence restrain them effectively when particles are of a lowposition and speed, and will absorb particles of a greater diameter more easily, thoseparticles of a high speed and small diameter are more active and then cost more dustpollution, the downriver fence of a coal pile is of little use when there are each porousfence in front of and back of pile.
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