露天煤尘污染扩散运动的数值计算

为探求煤尘污染运动的影响范围和浓度，以便采取有效措施治理露天煤场在自然风力作用下产生的煤尘对矿区环境的污染问题,以Discrete Particle Model离散介质的气-固两相流模型为理论依据，采用数值计算方法，计算了该矿区年平均风速和最大风速下煤尘粒子的浓度分布.结果表明：在年均风速3.3 m/s时，在煤垛下风向1 km范围内降尘浓度超标.利用Lagrange迹点跟踪法，得出颗粒物从吹起到随气流运动直至稳定扩散的全过程中各时刻污染颗粒在大气中的扩散云图.结果显示：气流在煤垛表面的持续作用，增大了煤尘粒子起跳的动量，促使粒子的跃移和悬浮运动，造成污染浓度的增大.

Numerical calculation of mine powder diffusion movement

To research the mine powder pollution scope and concentration values so as to make measures to utilize the heavy pollution caused by wind-blown mine powder,the numerical method was adopted based on Discrete Particle Model from the gas-solid flow theory.The concentration distributions were obtained at average and maximum wind velocity,respectively.The results show the concentration value of 1 km distance along leeward direction is beyond environment standard when the wind speed is 3.3 m/s.Moreover,Lagrange trail method was used to get the powder diffusion contour at different time,then the whole process was described including powder particle jump-starting,dispersing with the air and steady diffusing.The results indicate the air continuously blowing the powder can add particle momentum and make more particles jump off plies,which leads suspended particle concentration value to become greater.