3D flow around a rectangular cylinder: a computational study.

The aim of this paper is to provide a contribution to the study of the 3D, high Reynolds number, turbulent, separated and reattached flow around a fixed rectangular cylinder with a chord-to-depth ratio of 5. In spite of the simple geometry, it is believed that the problem could be of interest not only for fundamental research purposes, but also to provide useful information on the aerodynamics of a wide range of bluff bodies of interest in Civil Engineering (e.g. long span bridge decks, high-rise buildings, and so on) and in other Engineering applications. First, the obtained main aerodynamic integral parameters are compared with those proposed in literature. Second, the 3D features of the flow are investigated by means of both Proper Orthogonal Decomposition and coherence function of the side-surface fluctuating pressure field. Once the main 2D nature of the flow has been pointed out, some of the 2D mechanisms that are responsible for the variation of the fluctuating aerodynamic forces are scrutinised: the computational approach post-processing facilities are employed to look for significant relationships between the flow structures, pressure field and aerodynamic forces