Pedestrian wind comfort around buildings: Comparison of wind comfort criteria based on whole-flow field data for a complex case study

Assessment of pedestrian wind comfort around buildings requires the combination of wind statistics from a meteorological station, aerodynamic information and a comfort criterion. A wide range of different comfort criteria exist. In the past, several comparison studies of comfort criteria have been made. In the present paper, a different approach is pursued. The goal of this paper is threefold: (1) to provide an illustrative case study based on CFD as a framework for the comparison of different criteria; (2) to compare and evaluate the results by the different criteria as part of a complete wind comfort assessment study; and (3) to stress the importance of standardization of the wind comfort assessment procedure. The case study area is the campus of Eindhoven University of Technology. The 3D steady Reynolds-averaged Navier-Stokes (RANS) equations and the realizable k-e{open} model are used to provide part of the aerodynamic information. The CFD simulations are performed on a high-resolution grid based on grid-sensitivity analysis. Validation is conducted with on-site measurements. Part of the wind comfort assessment procedure is performed with the Dutch wind nuisance standard NEN 8100. The criteria compared in this study are the four complete criteria by Isyumov and Davenport (1975), Lawson (1978), Melbourne (1978) and NEN 8100 (2006). It is shown that the different criteria can lead to very different conclusions about the wind comfort. Because the outcome of wind comfort studies is often decisive in granting building permits, this illustrates the importance of wind comfort standardization, in particular concerning the comfort criterion.