A STUDY ON THE APPLICABILITY OF TWO-EQUATION TURBULENCE MODELS FOR TWO TYPES OF URBAN FORM

Abstract

This study examined applicability of the two-equation turbulence model for two types of urban form in wind environment assessment. The study was based on two benchmark tests. The first was Case E in a benchmark test by Architectural Institute of Japan. The second was a benchmark test based on a wind tunnel test using the 3D city model "PLATEAU" (Tokyo Metropolitan Government Building and surrounding buildings). Based on these two benchmark tests, we compared the accuracy with CFD using four two-equation turbulence models. For the accuracy evaluation, four metrics were used: the COST732 validation metrics (FAC2, NMSE, and FB) plus MAPE. The results showed that RNGkEpsilon or kEpslion was highly accurate for AIJ Case E, and kOmegaSST or RNGkEpsilon was highly accurate for Case PLATEAU. Furthermore, given the wind comfort ranks, it was considered RNGkEpsilon suitable for the case of selecting a single turbulence model for two types of urban form.