摘要
开放性颗粒物源强释放强度是大气防治领域中重要的基础参数.以平顶椭圆颗粒料堆为例,建立了流场计算的动力学模型,采用kε-模式封闭湍流模型,预测了料堆表面的流动特征,与美国国家环保局(EPA)风洞实验结果吻合很好.以现场实验测定为佐证,不仅验证了计算模型的可靠性,而且通过数据拟合,确定了堆料表面的粗糙度为0.30 m;提取该高度下的风速分布,得到了料堆表面每个网格节点处的摩阻风速值.并以EPA源强估算为基准,统计出风速为5.0m/s,风向0°时的料堆源强量.其结果与EPA模式相比,相差仅为8.11%.这不仅突破了EPA风洞实验数据的局限,而且解决摩阻风速的求解问题,对该类源强的估算供了新的量化手段和途径.
As a critical basic parameter in the field of air pollution control,dust emission of open-air source is particularly important.Oval pile with flattop was taken as an example and fluid dynamic mode closed by k-ε turbulence model was used to predict the characteristics of the air flow over the surface of the pile.The calculated velocities distributions over pile surface were in good agreement to the ones measured in the wind tunnel.And then the measurement results obtained in the actual open yard further verified the reliability of the dynamic mode and subsequently,the roughness of the sampled pile was determined to be an 30 cm by an approach of data fitting.At the results,velocities on roughness height above pile surface at each grid node were supposed the friction velocities.Using EPA equations,the emission factor was calculated under the conditions of 5.0 m/s wind velocity and 0°wind direction.The difference of dust emission between EPA and dynamic mode was only 8.11%.The results show that the dynamic mode broadens the limit data from the wind tunnel tested by EPA and solves the problem of obtaining friction velocity over pile surface.It provides a novel way for dust emission estimation of wind-blown particulate source.
出处
《中国矿业大学学报》
EI
CAS
CSCD
北大核心
2011年第5期823-828,共6页
Journal of China University of Mining & Technology
基金
国家自然科学基金项目(50808115)
山东省自然科学基金项目(2009ZRB01240)
