摘要
为了解城市建筑群对周围风场结构的影响,本文利用大涡模拟方法对不同建筑群分布类型下的风场状况进行了模拟,并利用通风指数对风场进行定量评估。模拟结果表明:PALM(Parallelized LES model)能够反映出建筑物影响下风场的结构特征。建筑群风场受到建筑高度、高度方差、分布、初始入流的影响。风场衰减主要体现在水平分量上,尤其是平均高度较高、高度方差大、交错不规整分布使得水平方向风场衰减、通风效果变差,而同时又会使得垂直风速分量w增大,增大垂直方向的空气交换速率。初始入流不会影响风场风廓线形态,在低层风场中平均风速大小以及总体空气交换速率基本与入流成正比关系。
In order to learn the influences of urban buildings on the surrounding wind fields, the wind fields of different types of buildings with the large-eddy simulation were simulated and the wind fields with various ventilation indexes were quantitatively assessed. Results show that PALM （Parallelized LES Model） can basically reflect the structures of the wind fields. Wind fields are affected by the building height, height variance and initial flow. The flow attenuation is mainly reflected in the horizontal compo- nent, especially when the average height is higher or with larger height variance and irregular distribution, the horizontal wind field would attenuate more with ventilation effect becoming worse. Meanwhile, the vertical velocity component w increases, so that the air exchange rate in the vertical direction would be larger. The initial flow does not affect the wind profile in shape, when the wind speed in lower height and the overall air exchange rate are proportional to the initial flow.
出处
《气象科学》
北大核心
2018年第1期85-94,共10页
Journal of the Meteorological Sciences
基金
国家重点研发计划(2016YFC0200501)
国家自然科学基金资助项目(41375014
51538005
41675008)
关键词
城市建筑群
风场结构
大涡模拟
Urban buildings
Wind fields structure
Large-eddy simulation
