Abstract
The streamlined exterior shapes of tall buildings are important to reduce the effect of the wind. Therefore, an examination of different techniques for the exterior design of tall buildings is required. This study aims to analyses some tall buildings to select the most streamlined design in order to reduce high wind risks. The benchmark used in the current study is a building with a height of 120 m and a triangular cross-section with a side length of 20 m. A square cross-section twisted building design is used as a modified model in tall buildings of about 120 m. The rotation angle of the building is 45° for each twisted path. Six configurations of this type of building are tested with different radiuses of fillet on their edges, which are 0, 1, 2, 3, 4, and 5 m respectively. All geometries of the buildings are created by SolidWorks, while mesh and simulations are achieved using ANSYS Fluent. Great agreement is obtained between the current results and the previous related study for the benchmark. Using twisted buildings with a fillet of 5 m can lead to a reduction of the drag coefficient of about 27.5% relative to the benchmark. Wind in a horizontal direction can be reduced by using twisted geometry. But in terms of separation, using a fillet with a large radius can lead to avoid early separation of air.