Abstract
Computational fluid dynamics (CFD) analysis using large-eddy simulation (LES) and standard k-ε model (k-ε) was conducted for flow within and above urban canyon under various conditions of thermal stratification. The results of LES and k-ε were compared with the wind tunnel experiment to investigate the prediction accuracy of CFD analysis. k-ε failed to reproduce the spatial distribution of the mean wind velocity vector and mean temperature within the urban canyon compared with LES in unstable case. k-ε underestimated the Reynolds stress <u1’u3’> and turbulent heat flux <u3’T’> within the urban canyon in unstable case. It is thought that the prediction accuracy of k-ε decreases because k-ε underestimates the exchange of momentum and heat within and above the urban canyon compared with LES and the wind tunnel experiment.
