Numerical Investigation and Comparative Study of Aerodynamic Characteristics in Rectangular, Corner Cut and Chamfered Sections by Using LES

In recent years, the length of bridges increases, and the main towers are becoming taller, thus it is necessary to improve the wind resistant performance of their main towers. Currently, corner-cut and chamfered cross-sections are used as static countermeasure of vibration in towers. However, there were some cases of vortex excitation due to the wind direction and cross-sectional shape when the main tower of a real cable-stayed bridge was examined. Therefore, it is required to examine the effective cross-section by understanding the flow and how corner-cut controls the separated flow. In this study, a comparative study of rectangular, corner-cut, and chamfered cross sections was conducted by using computational fluid dynamics analysis. It was confirmed that the drag coefficient and the variation components of lift coefficients were smaller in the corner-cut and chamfered cross sections than in the rectangular cross sections. It was also confirmed that the width of the separated flow was smaller in the corner-cut and chamfered cross section than in the rectangular cross section, and the pressure loss at the top surface and in the wake was also smaller. In addition, there was no significant difference in the aerodynamic characteristics between the corner cut and chamfered cross sections.