输煤巷道通风排尘特征参数数值模拟优化研究

针对输煤巷道煤炭运输过程中煤尘污染问题,利用数值模拟的方法,对不同风速下的煤尘颗粒运移规律、巷道底板沉积煤尘粒子扬尘规律进行模拟。通过对两种模拟结果进行对比分析,确定在一般干燥巷道中排尘风速以1.5～2.7 m/s为宜,既有利于粒径小于24μm的煤尘颗粒排出井外,也有利于粒径大于24μm的煤尘颗粒沉降;并且风速+带速不超过4m/s为宜,可以把粒径小于30μm的煤尘颗粒排出井外,很好地起到风流稀释作用。并与现场实测结果进行对比,结论基本一致。

New numerical simulation for optimizing the characteristic parameters of ventilation dedusting in the coal conveyer roadway

To solve the problem of coal dust pollution in the coal-transferring process,this paper has developed a brand-new numerical simulation to optimize the characteristic parameters of ventilation dedusting in the coal conveyer roadway.The said numerical simulation model is to simulate the discipline of transportation and movement of the coal dust particles under different wind velocities and raising of the deposited dust at the bottom floor of the roadway.For this purpose,we have determined the proper dust emission velocity(at 1.5-2.7 m/s) in the common dry roadway through a comparative analysis of the results of two kinds of simulations and the benefit of the settling down of the coal dust particles with average size bigger than 24 μm,because it is good for the coal dust particles of such size to settle down.And,it is under such a wind condition that the coal dust concentration for the fixed dust generation tends to decrease along with the increase of the wind speed.And,it is in such a case the wind velocity may play a role of dilution for the coal dust.If the wind velocity exceeds a certain level,the coal dust concentration would increase with the increase of the velocity,because the settled-down coal dust would be blown up again,and in this case the wind velocity functions as a blown-up rather than dilution.According to the actual condition of the coalmine,the wind would flow in an opposite direction to the belt movement.The total velocity of the wind and belt should not exceed 4 m/s,which may help to blow the coal dust with a particle size that is less than 30 μm out of the roadway and may also kindly dilute the coal dust. As compared with the results of the actual on-spot testing and measurement,they are basically consistent for all the air-flowing conditions.