TY - JOUR
T1 - Equivalent wind incidence angle method
T2 - A new technique to integrate the effects of twisted wind flows to AVA
AU - Weerasuriya, A. U.
AU - Tse, K. T.
AU - Zhang, Xuelin
AU - Kwok, K. C.S.
N1 - Publisher Copyright:
© 2018 Elsevier Ltd
PY - 2018/7
Y1 - 2018/7
N2 - This paper presents a novel and cost-effective method to replicate modified pedestrian level wind (PLW) fields in twisted winds using a conventional wind profile with similar wind speeds and turbulent intensities. The novel method, namely the Equivalent Wind Incidence Angle (ϕEq) method was developed using data of PLW fields near five isolated buildings with aspect ratio (height:width) ranging from 4:1 to 0.5:1 subjected to two twisted wind profiles with the maximum clockwise yaw angles of 13° and 22°. The magnitude of ϕEq was found to be 6° and 14° for the two twisted wind profiles with maximum yaw angles of 13° and 22° and for any clockwise wind incidence angle ϕ, ϕEq is ϕ +6°, and ϕ +14°. The ϕEq method was applied for an Air Ventilation Assessment (AVA) done for an urban site in Hong Kong, and the outcomes were compared with two similar AVAs conducted using the two twisted wind profiles and a conventional wind profile without ϕEq. The comparison revealed that velocity ratios (VRs) and wind speeds with a 50% probability of exceedance are similar or slightly different from those in twisted winds if the conventional wind profile is combined with the ϕEq method.
AB - This paper presents a novel and cost-effective method to replicate modified pedestrian level wind (PLW) fields in twisted winds using a conventional wind profile with similar wind speeds and turbulent intensities. The novel method, namely the Equivalent Wind Incidence Angle (ϕEq) method was developed using data of PLW fields near five isolated buildings with aspect ratio (height:width) ranging from 4:1 to 0.5:1 subjected to two twisted wind profiles with the maximum clockwise yaw angles of 13° and 22°. The magnitude of ϕEq was found to be 6° and 14° for the two twisted wind profiles with maximum yaw angles of 13° and 22° and for any clockwise wind incidence angle ϕ, ϕEq is ϕ +6°, and ϕ +14°. The ϕEq method was applied for an Air Ventilation Assessment (AVA) done for an urban site in Hong Kong, and the outcomes were compared with two similar AVAs conducted using the two twisted wind profiles and a conventional wind profile without ϕEq. The comparison revealed that velocity ratios (VRs) and wind speeds with a 50% probability of exceedance are similar or slightly different from those in twisted winds if the conventional wind profile is combined with the ϕEq method.
KW - Air ventilation assessment
KW - Twisted wind profile
KW - Urban wind environment
KW - Wind incidence angle
UR - http://www.scopus.com/inward/record.url?scp=85047088043&partnerID=8YFLogxK
U2 - 10.1016/j.buildenv.2018.05.017
DO - 10.1016/j.buildenv.2018.05.017
M3 - Article
AN - SCOPUS:85047088043
SN - 0360-1323
VL - 139
SP - 46
EP - 57
JO - Building and Environment
JF - Building and Environment
ER -