LAUSR

Abstract Shape modification effectively reduces the wind loading and wind-induced vibrations of slender structures. Large-eddy simulation is used to investigate the flow around multiple square-like cylinders at a Reynolds number of 22,000. Based on a standard square cylinder, six square-like cylinders are simulated with sharp/rounded corners and straight/concave/convex sides. The combination of rounded corners and convex sides enables the best aerodynamic performance. Furthermore, a parametric study on the round-convex cylinder is conducted considering a fixed corner radius and various side curvatures B/K (B: nominal side length; K: side radius). The results show that both the aerodynamic characteristics of and the flow features around the cylinder change considerably with varying B/K and that three distinct flow regimes are observed. In Stage I (0 ≤ B/K ≤ 0.71), the flow separates at the front corners, and the aerodynamic forces decrease gradually. In Stage II (0.71