矿区风场CFD数值模拟研究——以中国内蒙古乌海市新星煤矿为例

CFD Simulation of Wind Field Characteristics in Mining Areas: A Case Study of the Xinxing Coal Mine in Wuhai City, Inner Mongolia, China

在中国西北干旱区,大量煤矿开采导致植被退化,强风发生概率增大。风场特征直接影响着沙尘的输运过程。为获取矿区风场特征,本文以内蒙古乌海新星煤矿为例,采用RANS湍流模型,利用开源软件OpenFOAM进行了CFD数值模拟。基于矿区多个观测点的风场实测结果,对数值模拟结果进行了验证,并讨论了西风、西北风和东风三个风向下矿区平均风速和湍动能的分布规律。结果表明:矿区东西两侧凸起的高山或丘陵对矿区平均风速分布影响较大;当风从西或东方向来袭时,由于尾流效应的影响,高地下游平均风速相对较小;而湍流动能则表现出较大的数值。对于西北风向,山或丘陵的尾流效应不太明显;同样,在低洼矿坑附近,平均风速减小,湍流动能增大。本研究可为矿区风沙防治及风沙建设提供理论依据。

The large amount of coal mining activity in the arid region of northwestern China leads to vegetation degradation and a greater probability of strong winds.The characteristics of windy fields directly affect the sand-dust transportation process.To capture the wind field characteristics in a mining area,numerical simulation of computational fluid dynamics(CFD)was conducted using the Reynolds-Averaged Naiver-Stokes(RANS)turbu-lence model based on open source software OpenFOAM,taking Xinxing Coal Mine in Wuhai,Inner Mongolia,China as an example.The field test results at several observation points in the mining area were adopted for vali-dating the numerical results.The distributions of mean wind speed and turbulence kinetic energy in the mining area for the W,NW and E wind directions are discussed.The results show that the mean wind speed distribu-tions of the mining area are greatly affected by the raised mountains or hills on the eastern and western sides.When the approaching wind comes from the W and E directions,the mean wind speed is relatively low behind the raised terrain due to the wake effect.However,the magnitude of turbulent kinetic energy shows a relatively large value.The wake effect of mountains or hills is less pronounced as the approaching wind comes from the NW direction.The reduced mean wind speed and increased turbulence kinetic energy are also observed near the low-lying pits in the mining area.The results of this study can provide a theoretical basis for the prevention and control of aeolian sand and its construction in mining areas.