Coherent structures in a flow past a circular cylinder at critical and super-critical Reynolds numbers

Abstract

It is well known that the wake topology in the flow past a circular cylinder remains almost unchanged up to Reynolds number ~105 Williamson (Annu Rev Fluid Mech 28(1), 477–539 (1996)) [1]. Then, at Re~2×105 major changes take place entailing flow separation, turbulence transition in the detached shear layers, reattachment of the flow and further separation of the boundary layer. In the present work, large-eddy simulations of the flow past a cylinder at Reynolds numbers in the range 2.5×105-106 are performed. This range includes both critical and super-critical Reynolds numbers (J Fluid Mech 10(3), 345–356 (1961)) [2]. Contradicting results about the wake configuration and structures are found in the literature.