Impact of Turbulence Models of Wind Pressure on two Buildings with Atypical Cross-Sections

Abstract

The article deals with the numerical analysis of the wind pressure distribution on a group of two high-rise buildings of different shape for different wind directions. The first building has the shape of a circular cylinder and the second was created by a combination of semicircles and a longitudinal member. The floor plan of the second building was similar to the letter S. The simulations were realized as 3D steady RANS. CFD results were compared with experimental measurements in the wind tunnel of the Slovak University of Technology in Bratislava. The results were processed using statistical methods such as correlation coefficient, fractional bias and fraction of data within a factor of 1.3, which determined the most suitable CFD model. The purpose of the present article was to verify the distribution of the external pressure coefficient on scale models at a scale of 1:350, which are located in the Atmospheric Surface Layer (ASL). In numerical modeling, the most important thing was to ensure similarity with the flow in the experimental Atmospheric Boundary Layer (ABL) and with the flow around the models. SST k–ω was evaluated as the most suitable turbulent model for the given type of problem. Turbulent models had a decisive influence on the overall distribution of external wind pressures on objects. The results showed that the most suitable orientation of the objects in terms of the external wind pressure coefficient is 0°, when the cylinder produced a shielding effect, with min mean cpe = −0.786. The most unfavorable wind effects were shown by the wind direction of 90° and 135° with the value min mean cpe = −1.361.

Keywords

• atypical cross-section
• external pressure coefficient
• wind tunnel
• computational fluid dynamics