CFD evaluation of wind speed conditions in passages between parallel buildings—effect of wall-function roughness modifications for the atmospheric boundary layer flow

CFD analysis of cross-ventilation of a generic isolated building with asymmetric opening positions: Impact of roof angle and opening location

“…They adhere to the best practice guidelines by Franke et al [76] and Tominaga et al [77], apart from the upstream length, which is reduced to 3 times the height of the building to limit the development of unintended streamwise gradients [78,79]. The dimensions of the domain are 0.9 x 1.54 x 0.48 m 3 (W x D x H) which correspond to 180 x 308 x 96 m 3 in full scale.…”

“…zero normal velocity and zero normal gradients of all variables. As recommended by Blocken et al [78,79], to assess the extent of unintended streamwise gradients (i.e. horizontal inhomogeneity) in the vertical profiles of mean wind speed and turbulent properties, a simulation in an empty computational domain is made using the shear-stress transport (SST) k-ω model [86].…”

CFD simulation of wind flow over natural complex terrain: Case study with validation by field measurements for Ria de Ferrol, Galicia, Spain

“…The importance of correct ground roughness specification for the accuracy of CFD simulation results in general was mentioned and/or demonstrated in earlier research (e.g. Richards and Hoxey 1993, Blocken et al 2007a, 2007b, Hargreaves and Wright 2007, Franke et al 2007, Gorlé et al 2009, Yang et al 2009, Richards and Norris 2011, Parente et al 2011. The importance of surface roughness for wind flow over complex terrain in particular was also stressed by several previous authors (Lun et al 2003, Prospathopoulos and Voutsinas 2006, Cao and Tamura 2006, 2007,Wakes et al 2010, Cao et al 2012.…”

CFD simulation of pedestrian-level wind conditions around buildings: Past achievements and prospects

“…The geometry, porosity and position of the windbreaks were varied, and also different building heights, wind directions, turbulence models and discretization schemes were included in the analysis. Blocken et al (2007) simulated the wind-flow pattern in passages between parallel buildings and compared the results with wind-tunnel measurements by Stathopoulos and Storms (1986). They also indicated the importance of appropriate boundary conditions (inlet profiles and wall functions) to obtain accurate results in CFD simulations of pedestrian-level winds.…”

“…It is well known that these choices can have a very large impact on the results. Several of these BPG documents were established specifically for the assessment of pedestrian-level wind conditions (Franke et al 2004, Blocken et al 2007, Tominaga et al 2008. Other, more general guidelines, but also of relevance to pedestrian-level wind conditions, are those by Casey and Wintergerste (2000), Jakeman et al (2006), Franke et al (2007 and Blocken and Gualtieri (2012).…”