Structure of turbulence in a flow around a rectangular cylinder

Abstract

The behaviour of the flow over a finite blunt plate with square leading and trailing edge corners at moderate Reynolds number is studied by means of a Direct Numerical Simulation. The chord-to-thickness ratio of the plate is 5 and the Reynolds number is Re = U∞ · D/ν = 3 × 103 where U∞ and D are the free-stream velocity and the thickness, respectively. The flow separates at the leading edge corner developing in a strong free-shear. The flow reattaches on the solid surface upstream the trailing edge and evolves in typical large-scale shedding beyond it. To the authors knowledge, this is the first time that high-fidelity three-dimensional data are produced to analyze in detail the flow features of such a system. Preliminary results on the flow topology will be presented in this work. In particular, the streamlines of the mean flow and the instantaneous three-dimensional turbulent structures via λ2 vortex criterion will be examinated.