Development of practical computational fluid dynamics procedures for generating horizontally homogeneous atmospheric boundary layer profiles for wind engineering applications

Simulations for wind engineering applications require fully-developed boundary layer approach flow with horizontal homogeneity and zero pressure gradient for accurate characterization of wind fields and the associated aerodynamic pressure on structures. Most numerical approaches using computational fluid dynamics (CFD) have focused on achievement of such approach flows in computational domains whose heights are equal to or less than the atmospheric boundary layer (ABL) height. However, simulations for specific wind engineering applications, such as wind over topographic features or in urban environments, could require the approach flow in domains whose top boundaries are higher than the ABL height because the limited domain height might distort the flow field of interest. Thus, this study proposes a novel approach to create the desired horizontally homogeneous and zero pressure gradient flow characteristics, in a vertically extended computational domain whose height is greater than the ABL depth. The proposed procedure is applied to simulations with various topographic features to investigate the effect of simulation conditions on the flow field of interest over the topography.