Simulation of wind response of tall buildings using computational fluid dynamics - a case study

Abstract

few decades. Interaction of wind with buildings with complex geometry leads to a complex building-wind environment. However, all codes of practice and standards are only applicable for buildings with simple geometry and height limitations. Moreover, all wind codes mainly present static based calculation. Generally, the static analysis is suitable only for structures less than 50 m height. Therefore, the actual wind effect is difficult to assess by the wind loading codes, hence recommend using Computational Fluid Dynamics (CFD) models. In this research, wind loads and its effects are calculated on a 31-storey high rise building utilizing three different international wind loading codes/standards, namely CP3 CHAPTER V-2:1972, BSEN 1991-4:2005 with SLS EN 1991-1-4:2019, AS/NZ 1170.2:2011 by encountering different factors and methods specified. The estimated forces are compared with each other since the different codes introduced different factors to estimate wind turbulent characteristics. Numerical Simulation has been carried out for the same building using RANS approach (Spalart-Allmaras). Comparison is carried out between the results obtained from simulation and code based calculations. This study has been used to evaluate the applicability / limitations of codes of practice via numerical simulation and identify the more suitable wind loading code. AS/NZS 1170.2:2011 is more suitable to evaluate the wind loads and their effects on tall buildings due to its advanced flow parameters. In addition, S-A turbulent model well performed in evaluating the complex building – wind environment accurately and different flow features such as vortices, wake formations etc. are clearly observed. The advantages of commercially available CFD software on complex fluid -structure problems has been discussed in terms of time, cost and accuracy of results opposed to other methods such as codes of practice and wind tunnel testing.