Computational Fluid Dynamics study on the performance and mechanism of suction control over a high-rise building

In order to reduce the wind-induced drag and improve the wind-resistance performance of a high-rise building, active suction control was proposed to investigate its drag-reducing property through Computational Fluid Dynamics (CFD) method. The numerical method was validated by the experiment of suction control over a backward-facing step flow. Effects of the dimensionless suction flux, the suction angle and the slot size on drag reduction for a high-rise building model were analysed, and the detailed flow fields (including the time-averaged stream and vorticity fields), the boundary layer development and turbulence characteristics like turbulent kinetic energy for the suction models were presented to discuss the mechanism of suction control. The results indicate that suction is very effective in reducing the wind-load of a high-rise building model, and only the dimensionless suction flux is important, while the orifice geometrical parameters and the suction velocities show little influence on drag reduction. The mechanism of suction control is concluded that suction can bring more flows around the windward face, restrain the flow separation and decrease the width of the wake for the suction models. Copyright (c) 2010 John Wiley & Sons, Ltd.