高落差粉尘扩散规律和分布特征

高溜井放矿过程中会形成强大的冲击气流引起粉尘扩散，造成严重的井下环境污染，对其进行有效治理一直是井下通风除尘的工作重心，本工作利用相似实验和数值模拟相结合的方式探究溜井放矿过程中粉尘的扩散规律和分布特征。通过改变放矿质量、矿石粒径、溜井密闭程度、含水率等因素测试不同条件下气流大小和粉尘浓度分布，并利用CFD-DPM耦合方法模拟卸矿过程中的气?固两相流，研究气流和粉尘浓度时空分布特征。结果表明，最大粉尘浓度和风速随放矿质量增加而上升，随颗粒粒径和溜井密闭程度增大而降低，且含水率越大，粉尘浓度越小，风速无明显变化，在放矿过程中矿石颗粒之间碰撞占主导作用，颗粒流呈横向分布。

The diffusion law and distribution characteristics of high drop dust

In the process of ore drawing in high pass, a strong impact airflow will be formed, which will cause dust diffusion and serious underground environmental pollution. The effective treatment of the pollution has always been the focus of underground ventilation and dust removal. In this work, the diffusion law and distribution characteristics of dust in the process of ore pass drawing are explored by means of the combination of similar experiment and numerical simulation. By changing the experimental conditions of ore drawing quality, ore particle size, chute sealing degree, water content and other factors, the air flow size and dust concentration distribution under different conditions were researched. The CFD-DPM coupling method was used to simulate the gas?solid two-phase flow in the process of ore unloading, and the temporal and spatial distribution characteristics of gas flow and dust concentration were studied. The results showed that the maximum dust concentration and wind speed increased with the increase of ore drawing quality, and decreased with the increase of particle size and airtight degree of ore pass. The higher the water content was, the smaller the dust concentration was, but the wind speed had no obvious changed. Moreover, the key factor affecting dust concentration was water content, followed by the airtight degree of ore pass, ore drawing quality and ore particle size. In the process of ore drawing, the collision between ore particles played a dominant role, and the particle flow presented a transverse distribution.