Study on the dynamic characteristics of flow over building cluster at high Reynolds number by large eddy simulation  

作　　者：WANG BoBin WANG ZhiShi CUI GuiXiang ZHANG ZhaoShun 

机构地区：[1]Department of mechanical engineering,Tsinghua University [2]Department of Civil and Environmental Engineering,University of Macao

出　　处：《Science China(Physics,Mechanics & Astronomy)》2014年第6期1144-1159,共16页中国科学：物理学、力学、天文学（英文版）

基　　金：supported by the University of Macao(Grant No.MYRG157(Y3-L2)-FST11-WZS);the National Natural Science Foundation of China(Grant No.11132005),;MOST-2011BAK07B01-03,LIAMA Project TIPE;the National Laboratory for Information Science and Technology

摘　　要：In this paper,the dynamic characteristics of building clusters are simulated by large eddy simulation at high Reynolds number for both homogeneous and heterogeneous building clusters.To save the computational cost a channel-like flow model is applied to the urban canopy with free slip condition at the upper boundary.The results show that the domain height is an important parameter for correct evaluation of the dynamic characteristics.The domain height must be greater than 8h(h is the average building height)in order to obtain correct roughness height while displacement height and roughness sublayer are less sensitive to the domain height.The Reynolds number effects on the dynamic characteristics and flow patterns are investigated.The turbulence intensity is stronger inside building cluster at high Reynolds number while turbulence intensity is almost unchanged with Reynolds number above the building cluster.Roughness height increases monotonously with Reynolds number by 20%from Re*=103 to Re*=105 but displacement height is almost unchanged.Within the canopy layer of heterogeneous building clusters,flow structures vary between buildings and turbulence is more active at high Reynolds number.In this paper, the dynamic characteristics of building clusters are simulated by large eddy simulation at high Reynolds number for both homogeneous and heterogeneous building clusters. To save the computational cost a channel-like flow model is ap- plied to the urban canopy with free slip condition at the upper boundary. The results show that the domain height is an im- portant parameter for correct evaluation of the dynamic characteristics. The domain height must be greater than 8h （h is the average building height） in order to obtain correct roughness height while displacement height and roughness sublayer are less sensitive to the domain height. The Reynolds number effects on the dynamic characteristics and flow patterns are investigated. The turbulence intensity is stronger inside building cluster at high Reynolds number while turbulence intensity is almost un- changed with Reynolds number above the building cluster. Roughness height increases monotonously with Reynolds number by 20% from Re＊=103 to Re＊=105 but displacement height is almost unchanged. Within the canopy layer of heterogeneous building clusters, flow structures vary between buildings and turbulence is more active at high Reynolds number.

关 键 词：building array high Reynolds number large eddy simulation 

分 类 号：TU312[建筑科学—结构工程]