Wind Environmental Conditions in Passages between Two Long Narrow Perpendicular Buildings

Abstract

This paper presents wind tunnel measurements of pedestrian wind conditions in passages between various configurations of two long narrow perpendicular buildings in open country exposure. The investigated parameters are passage width, building height and wind direction. The measurements were made along the passage centerline. The aim of the paper is to provide more insight in the pedestrian wind conditions in these basic building configurations, to address some contradictory statements reported in the literature and to provide detailed experimental data for Computational Fluid Dynamics (CFD) validation. The results show that the wind speed amplification factors in diverging passages are generally larger than in converging passages. It is also shown that the maximum wind speed amplification factors increase monotonically with decreasing passage width, contrary to some general building design guidelines proposed in the past for such building configurations. Significant issues concerning the use of the experimental data for CFD validation are also discussed. Passages between buildings can be responsible for increased wind speed and wind nuisance at pedestrian level (Ishizaki and Sung 1971, Wiren 1975, Lawson 1980, Beranek 1982, Stathopoulos and Storms 1986, Stathopoulos et al. 1992, Stathopoulos and Wu 1995, To and Lam 1995, ASCE 2003, Blocken et al. 2004, 2007a, Stathopoulos 2006. Different categories of passages between buildings can be distinguished, some of which are indicated in Fig. 1: (1) passages between parallel buildings placed side-by-side; (2) passages between parallel shifted buildings; and (3) passages between perpendicular buildings. This paper focuses on passages between perpendicular buildings. Depending on the wind direction, this type of passage can be called "converging passage" or "diverging passage". A distinction can also be made between two types of studies concerning wind conditions in passages: (1) fundamental studies, which are typically conducted for simple, generic building configurations as indicated in Fig. 1, to provide insight in the flow behavior, for parametric analyses and for CFD validation; and (2) applied studies for more complex building configurations. This paper will be limited to generic building configurations with only two buildings.Many fundamental studies of wind conditions in passages between buildings have been conducted in the past, by wind tunnel modeling and by numerical simulation with CFD. The majority of these studies focused on passages between parallel buildings. Pedestrian wind conditions in passages between nonparallel buildings have received much less attention. Wiren (1975) performed wind tunnel experiments for perpendicular buildings and for various wind directions (converging and diverging passages). Gandemer (1975) and Lawson (1980) reported wind tunnel results for converging passages. Beranek (1982) performed sand-erosion tests to compare the pedestrian wind conditions in perpendicular converging versus diverging building arrangements. Howe...

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