On the estimation of wind comfort in a building environment by micro-scale simulation

Abstract

A three-dimensional micro-scale model is used to study some aspects of wind comfort in a built-up area. The equations for calculating the mean wind have been extended by a Markov approach for short-term wind fluctuations. The model components have been successfully verified against wind tunnel measurements and observations of a field experiment. The simulated time series are used to estimate wind comfort measures. It turns out that the frequency of exceedance of prescribed thresholds depends strongly on the specification of the gust duration time. It was also possible to calculate the spatial distribution of a gust factor g depending on local wind characteristics. The simulated range is much broader than a value of g = 3-3.5 commonly used for wind comfort assessments. Again, the order of magnitude and the bandwidth of g depends strongly on the definition of a gust.