Numerical simulations of the transition from laminar to chaotic behaviour of the planar vortex flow past a circular cylinder

In the present paper the study of the two-dimensional flow field past a circular cylinder for Reynolds number up to 5 · 105 is addressed. A Lagrangian particle method approach has been exploited and the simulations have been performed with high spatial resolutions in order to resolve all the main vortical scales. Long simulation time evolutions have been performed in order to get the vortex shedding dynamics as well as the Fourier analysis of the loads. The adopted numerical method allows to discuss both local (boundary layer and near wake dynamics) and global (far wake dynamics) aspects of the problem.The fundamental aspects related to the different identified flow states as well as the drag crisis mechanism are investigated.