摘要
文章通过利用大涡模拟的方法,研究了不同建筑物高度和不同风速对建筑物周围流场的影响,并结合国控监测站点实测数据分析,探讨建筑物对监测点代表性的影响。结果表明:(1)在建筑物侧面和顶部区域风速明显增大,空腔区内流速明显降低,在建筑物背风侧尾流区随着气流逐渐远离建筑物,速度值与来流风速一致。(2)建筑物影响的绕流区范围与来流风速基本无关,主要受建筑高度影响;空腔区向下方向延伸的范围和横向范围分别是建筑物高度2.0~3.0倍和2.7~4.0倍,垂直向范围约是建筑物高度的1.3~1.6倍。(3)建筑物建成后监测点附近的流场和污染物浓度分布均发生明显变化,建筑物建成后局地风速明显降低、污染物浓度显著增加,使得监测点观测的监测数据不能代表该地区的空气质量水平,影响其代表性。
Large eddy simulation(LES)is used to study the influence of different building heights and different wind speeds on the flow field around the building,and based on the data of the site to analyze the representativeness of the monitoring points.The results show that the wind speed increases significantly in the side and top areas of the building,and the flow velocity in the cavity area is significantly reduced.The wake area in the leeward side of the building gradually moves away from the building with the airflow,the velocity value is consistent with the incoming wind speed.The range of the surrounding area affected by the building is basically independent of the incoming wind speed,mainly affected by the height of the building.The range and the cross-sectional range of the cavity area extending downward are about 2.0~3.0 times and 2.7~4.0 times of the height of the building,the vertical range is about 1.3~1.6 times the height of the building.After the building is completed,the flow field and pollutant concentration near the monitoring point have changed significantly.The wind speed near the building is significantly reduced,and the concentration of pollutants is significantly increased,so that the monitoring data observed at the monitoring point cannot represent the air quality level of the area and affect its representativeness.
作者
黄萌
王颖
秦闯
张晗
李博
HUANG Meng;WANG Ying;QIN Chuang;ZHANG Han;LI Bo(College of Atmospheric Science,Lanzhou University,Lanzhou 730000,China;Key Laboratory of Semi-arid Climate Change of the Ministry of Education,Lanzhou University,Lanzhou 730000,China)
出处
《环境科学与技术》
CAS
CSCD
北大核心
2019年第10期174-180,共7页
Environmental Science & Technology
关键词
数值模拟
LES
NOx
监测点
建筑物
numerical simulation
LES
NOx
monitoring station
building
